## GtkCellArea

GtkCellArea — An abstract class for laying out GtkCellRenderers

## Synopsis

    #include <gtk/gtk.h>

    struct              GtkCellArea;
    struct              GtkCellAreaClass;
    gboolean            (*GtkCellCallback)                  (GtkCellRenderer *renderer,
                                                             gpointer data);
    gboolean            (*GtkCellAllocCallback)             (GtkCellRenderer *renderer,
                                                             const GdkRectangle *cell_area,
                                                             const GdkRectangle *cell_background,
                                                             gpointer data);
    #define             GTK_CELL_AREA_WARN_INVALID_CELL_PROPERTY_ID(object,
                                                             property_id,
                                                             pspec)
    void                gtk_cell_area_add                   (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);
    void                gtk_cell_area_remove                (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);
    gboolean            gtk_cell_area_has_renderer          (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);
    void                gtk_cell_area_foreach               (GtkCellArea *area,
                                                             GtkCellCallback callback,
                                                             gpointer callback_data);
    void                gtk_cell_area_foreach_alloc         (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             const GdkRectangle *background_area,
                                                             GtkCellAllocCallback callback,
                                                             gpointer callback_data);
    gint                gtk_cell_area_event                 (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             GdkEvent *event,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags);
    void                gtk_cell_area_render                (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             cairo_t *cr,
                                                             const GdkRectangle *background_area,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags,
                                                             gboolean paint_focus);
    void                gtk_cell_area_get_cell_allocation   (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             GtkCellRenderer *renderer,
                                                             const GdkRectangle *cell_area,
                                                             GdkRectangle *allocation);
    GtkCellRenderer *   gtk_cell_area_get_cell_at_position  (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             gint x,
                                                             gint y,
                                                             GdkRectangle *alloc_area);
    GtkCellAreaContext * gtk_cell_area_create_context       (GtkCellArea *area);
    GtkCellAreaContext * gtk_cell_area_copy_context         (GtkCellArea *area,
                                                             GtkCellAreaContext *context);
    GtkSizeRequestMode  gtk_cell_area_get_request_mode      (GtkCellArea *area);
    void                gtk_cell_area_get_preferred_width   (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint *minimum_width,
                                                             gint *natural_width);
    void                gtk_cell_area_get_preferred_height_for_width
                                                            (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint width,
                                                             gint *minimum_height,
                                                             gint *natural_height);
    void                gtk_cell_area_get_preferred_height  (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint *minimum_height,
                                                             gint *natural_height);
    void                gtk_cell_area_get_preferred_width_for_height
                                                            (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint height,
                                                             gint *minimum_width,
                                                             gint *natural_width);
    const gchar *       gtk_cell_area_get_current_path_string
                                                            (GtkCellArea *area);
    void                gtk_cell_area_apply_attributes      (GtkCellArea *area,
                                                             GtkTreeModel *tree_model,
                                                             GtkTreeIter *iter,
                                                             gboolean is_expander,
                                                             gboolean is_expanded);
    void                gtk_cell_area_attribute_connect     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *attribute,
                                                             gint column);
    void                gtk_cell_area_attribute_disconnect  (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *attribute);
    void                gtk_cell_area_class_install_cell_property
                                                            (GtkCellAreaClass *aclass,
                                                             guint property_id,
                                                             GParamSpec *pspec);
    GParamSpec *        gtk_cell_area_class_find_cell_property
                                                            (GtkCellAreaClass *aclass,
                                                             const gchar *property_name);
    GParamSpec **       gtk_cell_area_class_list_cell_properties
                                                            (GtkCellAreaClass *aclass,
                                                             guint *n_properties);
    void                gtk_cell_area_add_with_properties   (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_prop_name,
                                                             ...);
    void                gtk_cell_area_cell_set              (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_prop_name,
                                                             ...);
    void                gtk_cell_area_cell_get              (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_prop_name,
                                                             ...);
    void                gtk_cell_area_cell_set_valist       (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_property_name,
                                                             va_list var_args);
    void                gtk_cell_area_cell_get_valist       (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_property_name,
                                                             va_list var_args);
    void                gtk_cell_area_cell_set_property     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *property_name,
                                                             const GValue *value);
    void                gtk_cell_area_cell_get_property     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *property_name,
                                                             GValue *value);
    gboolean            gtk_cell_area_is_activatable        (GtkCellArea *area);
    gboolean            gtk_cell_area_activate              (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags,
                                                             gboolean edit_only);
    gboolean            gtk_cell_area_focus                 (GtkCellArea *area,
                                                             GtkDirectionType direction);
    void                gtk_cell_area_set_focus_cell        (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);
    GtkCellRenderer *   gtk_cell_area_get_focus_cell        (GtkCellArea *area);
    void                gtk_cell_area_add_focus_sibling     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkCellRenderer *sibling);
    void                gtk_cell_area_remove_focus_sibling  (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkCellRenderer *sibling);
    gboolean            gtk_cell_area_is_focus_sibling      (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkCellRenderer *sibling);
    const GList *       gtk_cell_area_get_focus_siblings    (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);
    GtkCellRenderer *   gtk_cell_area_get_focus_from_sibling
                                                            (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);
    GtkCellRenderer *   gtk_cell_area_get_edited_cell       (GtkCellArea *area);
    GtkCellEditable *   gtk_cell_area_get_edit_widget       (GtkCellArea *area);
    gboolean            gtk_cell_area_activate_cell         (GtkCellArea *area,
                                                             GtkWidget *widget,
                                                             GtkCellRenderer *renderer,
                                                             GdkEvent *event,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags);
    void                gtk_cell_area_stop_editing          (GtkCellArea *area,
                                                             gboolean canceled);
    void                gtk_cell_area_inner_cell_area       (GtkCellArea *area,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             GdkRectangle *inner_area);
    void                gtk_cell_area_request_renderer      (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkOrientation orientation,
                                                             GtkWidget *widget,
                                                             gint for_size,
                                                             gint *minimum_size,
                                                             gint *natural_size);

## Object Hierarchy

      GObject
       +----GInitiallyUnowned
             +----GtkCellArea
                   +----GtkCellAreaBox

## Implemented Interfaces

GtkCellArea implements GtkCellLayout and GtkBuildable.

## Properties

      "edit-widget"              GtkCellEditable*      : Read
      "edited-cell"              GtkCellRenderer*      : Read
      "focus-cell"               GtkCellRenderer*      : Read / Write

## Signals

      "add-editable"                                   : Run First
      "apply-attributes"                               : Run First
      "focus-changed"                                  : Run First
      "remove-editable"                                : Run First

## Description

The GtkCellArea is an abstract class for GtkCellLayout widgets (also referred to as "layouting widgets") to interface with an arbitrary number of GtkCellRenderers and interact with the user for a given GtkTreeModel row.

The cell area handles events, focus navigation, drawing and size requests and allocations for a given row of data.

Usually users dont have to interact with the GtkCellArea directly unless they are implementing a cell-layouting widget themselves.

### Requesting area sizes

As outlined in GtkWidget's geometry management section, GTK+ uses a height-for-width geometry management system to compute the sizes of widgets and user interfaces. GtkCellArea uses the same semantics to calculate the size of an area for an arbitrary number of GtkTreeModel rows.

When requesting the size of a cell area one needs to calculate the size for a handful of rows, and this will be done differently by different layouting widgets. For instance a GtkTreeViewColumn always lines up the areas from top to bottom while a GtkIconView on the other hand might enforce that all areas received the same width and wrap the areas around, requesting height for more cell areas when allocated less width.

It's also important for areas to maintain some cell alignments with areas rendered for adjacent rows (cells can appear "columnized" inside an area even when the size of cells are different in each row). For this reason the GtkCellArea uses a GtkCellAreaContext object to store the alignments and sizes along the way (as well as the overall largest minimum and natural size for all the rows which have been calculated with the said context).

The GtkCellAreaContext is an opaque object specific to the GtkCellArea which created it (see `gtk_cell_area_create_context()`). The owning cell-layouting widget can create as many contexts as it wishes to calculate sizes of rows which should receive the same size in at least one orientation (horizontally or vertically), However, it's important that the same GtkCellAreaContext which was used to request the sizes for a given GtkTreeModel row be used when rendering or processing events for that row.

In order to request the width of all the rows at the root level of a GtkTreeModel one would do the following:

Example 66. Requesting the width of a handful of GtkTreeModel rows

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    GtkTreeIter iter;
    gint        minimum_width;
    gint        natural_width;

    valid = gtk_tree_model_get_iter_first (model, &iter);
    while (valid)
      {
        gtk_cell_area_apply_attributes (area, model, &iter, FALSE, FALSE);
        gtk_cell_area_get_preferred_width (area, context, widget, NULL, NULL);

        valid = gtk_tree_model_iter_next (model, &iter);
      }
    gtk_cell_area_context_get_preferred_width (context, &minimum_width, &natural_width);

Note that in this example it's not important to observe the returned minimum and natural width of the area for each row unless the cell-layouting object is actually interested in the widths of individual rows. The overall width is however stored in the accompanying GtkCellAreaContext object and can be consulted at any time.

This can be useful since GtkCellLayout widgets usually have to support requesting and rendering rows in treemodels with an exceedingly large amount of rows. The GtkCellLayout widget in that case would calculate the required width of the rows in an idle or timeout source (see `g_timeout_add()`) and when the widget is requested its actual width in `GtkWidgetClass.get_preferred_width()` it can simply consult the width accumulated so far in the GtkCellAreaContext object.

A simple example where rows are rendered from top to bottom and take up the full width of the layouting widget would look like:

Example 67. A typical `get_preferred_width()` implementation

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    static void
    foo_get_preferred_width (GtkWidget       *widget,
                             gint            *minimum_size,
                             gint            *natural_size)
    {
      Foo        *foo  = FOO (widget);
      FooPrivate *priv = foo->priv;

      foo_ensure_at_least_one_handfull_of_rows_have_been_requested (foo);

      gtk_cell_area_context_get_preferred_width (priv->context, minimum_size, natural_size);
    }

In the above example the Foo widget has to make sure that some row sizes have been calculated (the amount of rows that Foo judged was appropriate to request space for in a single timeout iteration) before simply returning the amount of space required by the area via the GtkCellAreaContext.

Requesting the height for width (or width for height) of an area is a similar task except in this case the GtkCellAreaContext does not store the data (actually, it does not know how much space the layouting widget plans to allocate it for every row. It's up to the layouting widget to render each row of data with the appropriate height and width which was requested by the GtkCellArea).

In order to request the height for width of all the rows at the root level of a GtkTreeModel one would do the following:

Example 68. Requesting the height for width of a handful of GtkTreeModel rows

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    GtkTreeIter iter;
    gint        minimum_height;
    gint        natural_height;
    gint        full_minimum_height = 0;
    gint        full_natural_height = 0;

    valid = gtk_tree_model_get_iter_first (model, &iter);
    while (valid)
      {
        gtk_cell_area_apply_attributes (area, model, &iter, FALSE, FALSE);
        gtk_cell_area_get_preferred_height_for_width (area, context, widget,
                                                      width, &minimum_height, &natural_height);

        if (width_is_for_allocation)
           cache_row_height (&iter, minimum_height, natural_height);

        full_minimum_height += minimum_height;
        full_natural_height += natural_height;

        valid = gtk_tree_model_iter_next (model, &iter);
      }

Note that in the above example we would need to cache the heights returned for each row so that we would know what sizes to render the areas for each row. However we would only want to really cache the heights if the request is intended for the layouting widgets real allocation.

In some cases the layouting widget is requested the height for an arbitrary for_width, this is a special case for layouting widgets who need to request size for tens of thousands of rows. For this case it's only important that the layouting widget calculate one reasonably sized chunk of rows and return that height synchronously. The reasoning here is that any layouting widget is at least capable of synchronously calculating enough height to fill the screen height (or scrolled window height) in response to a single call to `GtkWidgetClass.get_preferred_height_for_width()`. Returning a perfect height for width that is larger than the screen area is inconsequential since after the layouting receives an allocation from a scrolled window it simply continues to drive the the scrollbar values while more and more height is required for the row heights that are calculated in the background.

### Rendering Areas

Once area sizes have been aquired at least for the rows in the visible area of the layouting widget they can be rendered at `GtkWidgetClass.draw()` time.

A crude example of how to render all the rows at the root level runs as follows:

Example 69. Requesting the width of a handful of GtkTreeModel rows

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    GtkAllocation allocation;
    GdkRectangle  cell_area = { 0, };
    GtkTreeIter   iter;
    gint          minimum_width;
    gint          natural_width;

    gtk_widget_get_allocation (widget, &allocation);
    cell_area.width = allocation.width;

    valid = gtk_tree_model_get_iter_first (model, &iter);
    while (valid)
      {
        cell_area.height = get_cached_height_for_row (&iter);

        gtk_cell_area_apply_attributes (area, model, &iter, FALSE, FALSE);
        gtk_cell_area_render (area, context, widget, cr,
                              &cell_area, &cell_area, state_flags, FALSE);

        cell_area.y += cell_area.height;

        valid = gtk_tree_model_iter_next (model, &iter);
      }

Note that the cached height in this example really depends on how the layouting widget works. The layouting widget might decide to give every row its minimum or natural height or, if the model content is expected to fit inside the layouting widget without scrolling, it would make sense to calculate the allocation for each row at "size-allocate" time using `gtk_distribute_natural_allocation()`.

### Handling Events and Driving Keyboard Focus

Passing events to the area is as simple as handling events on any normal widget and then passing them to the `gtk_cell_area_event()` API as they come in. Usually GtkCellArea is only interested in button events, however some customized derived areas can be implemented who are interested in handling other events. Handling an event can trigger the "focus-changed" signal to fire; as well as "add-editable" in the case that an editable cell was clicked and needs to start editing. You can call `gtk_cell_area_stop_editing()` at any time to cancel any cell editing that is currently in progress.

The GtkCellArea drives keyboard focus from cell to cell in a way similar to GtkWidget. For layouting widgets that support giving focus to cells it's important to remember to pass `GTK_CELL_RENDERER_FOCUSED` to the area functions for the row that has focus and to tell the area to paint the focus at render time.

Layouting widgets that accept focus on cells should implement the `GtkWidgetClass.focus()` virtual method. The layouting widget is always responsible for knowing where GtkTreeModel rows are rendered inside the widget, so at `GtkWidgetClass.focus()` time the layouting widget should use the GtkCellArea methods to navigate focus inside the area and then observe the GtkDirectionType to pass the focus to adjacent rows and areas.

A basic example of how the `GtkWidgetClass.focus()` virtual method should be implemented:

Example 70. Implementing keyboard focus navigation

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    static gboolean
    foo_focus (GtkWidget       *widget,
               GtkDirectionType direction)
    {
      Foo        *foo  = FOO (widget);
      FooPrivate *priv = foo->priv;
      gint        focus_row;
      gboolean    have_focus = FALSE;

      focus_row = priv->focus_row;

      if (!gtk_widget_has_focus (widget))
        gtk_widget_grab_focus (widget);

      valid = gtk_tree_model_iter_nth_child (priv->model, &iter, NULL, priv->focus_row);
      while (valid)
        {
          gtk_cell_area_apply_attributes (priv->area, priv->model, &iter, FALSE, FALSE);

          if (gtk_cell_area_focus (priv->area, direction))
            {
               priv->focus_row = focus_row;
               have_focus = TRUE;
               break;
            }
          else
            {
              if (direction == GTK_DIR_RIGHT ||
                  direction == GTK_DIR_LEFT)
                break;
              else if (direction == GTK_DIR_UP ||
                       direction == GTK_DIR_TAB_BACKWARD)
               {
                  if (focus_row == 0)
                    break;
                  else
                   {
                      focus_row--;
                      valid = gtk_tree_model_iter_nth_child (priv->model, &iter, NULL, focus_row);
                   }
                }
              else
                {
                  if (focus_row == last_row)
                    break;
                  else
                    {
                      focus_row++;
                      valid = gtk_tree_model_iter_next (priv->model, &iter);
                    }
                }
            }
        }
        return have_focus;
    }

Note that the layouting widget is responsible for matching the GtkDirectionType values to the way it lays out its cells.

### Cell Properties

The GtkCellArea introduces cell properties for GtkCellRenderers in very much the same way that GtkContainer introduces child properties for GtkWidgets. This provides some general interfaces for defining the relationship cell areas have with their cells. For instance in a GtkCellAreaBox a cell might "expand" and receive extra space when the area is allocated more than its full natural request, or a cell might be configured to "align" with adjacent rows which were requested and rendered with the same GtkCellAreaContext.

Use `gtk_cell_area_class_install_cell_property()` to install cell properties for a cell area class and `gtk_cell_area_class_find_cell_property()` or `gtk_cell_area_class_list_cell_properties()` to get information about existing cell properties.

To set the value of a cell property, use `gtk_cell_area_cell_set_property()`, `gtk_cell_area_cell_set()` or `gtk_cell_area_cell_set_valist()`. To obtain the value of a cell property, use `gtk_cell_area_cell_get_property()`, `gtk_cell_area_cell_get()` or `gtk_cell_area_cell_get_valist()`.

## Details

### struct GtkCellArea

    struct GtkCellArea;

### struct GtkCellAreaClass

    struct GtkCellAreaClass {
      /* Basic methods */
      void               (* add)                             (GtkCellArea             *area,
                                                              GtkCellRenderer         *renderer);
      void               (* remove)                          (GtkCellArea             *area,
                                                              GtkCellRenderer         *renderer);
      void               (* foreach)                         (GtkCellArea             *area,
                                                              GtkCellCallback          callback,
                                                              gpointer                 callback_data);
      void               (* foreach_alloc)                   (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              const GdkRectangle      *cell_area,
                                                              const GdkRectangle      *background_area,
                                                              GtkCellAllocCallback     callback,
                                                              gpointer                 callback_data);
      gint               (* event)                           (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              GdkEvent                *event,
                                                              const GdkRectangle      *cell_area,
                                                              GtkCellRendererState     flags);
      void               (* render)                          (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              cairo_t                 *cr,
                                                              const GdkRectangle      *background_area,
                                                              const GdkRectangle      *cell_area,
                                                              GtkCellRendererState     flags,
                                                              gboolean                 paint_focus);
      void               (* apply_attributes)                (GtkCellArea             *area,
                                                              GtkTreeModel            *tree_model,
                                                              GtkTreeIter             *iter,
                                                              gboolean                 is_expander,
                                                              gboolean                 is_expanded);

      /* Geometry */
      GtkCellAreaContext *(* create_context)                 (GtkCellArea             *area);
      GtkCellAreaContext *(* copy_context)                   (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context);
      GtkSizeRequestMode (* get_request_mode)                (GtkCellArea             *area);
      void               (* get_preferred_width)             (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              gint                    *minimum_width,
                                                              gint                    *natural_width);
      void               (* get_preferred_height_for_width)  (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              gint                     width,
                                                              gint                    *minimum_height,
                                                              gint                    *natural_height);
      void               (* get_preferred_height)            (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              gint                    *minimum_height,
                                                              gint                    *natural_height);
      void               (* get_preferred_width_for_height)  (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              gint                     height,
                                                              gint                    *minimum_width,
                                                              gint                    *natural_width);

      /* Cell Properties */
      void               (* set_cell_property)               (GtkCellArea             *area,
                                                              GtkCellRenderer         *renderer,
                                                              guint                    property_id,
                                                              const GValue            *value,
                                                              GParamSpec              *pspec);
      void               (* get_cell_property)               (GtkCellArea             *area,
                                                              GtkCellRenderer         *renderer,
                                                              guint                    property_id,
                                                              GValue                  *value,
                                                              GParamSpec              *pspec);

      /* Focus */
      gboolean           (* focus)                           (GtkCellArea             *area,
                                                              GtkDirectionType         direction);
      gboolean           (* is_activatable)                  (GtkCellArea             *area);
      gboolean           (* activate)                        (GtkCellArea             *area,
                                                              GtkCellAreaContext      *context,
                                                              GtkWidget               *widget,
                                                              const GdkRectangle      *cell_area,
                                                              GtkCellRendererState     flags,
                                                              gboolean                 edit_only);
    };

`add` () | adds a GtkCellRenderer to the area.
`remove` () | removes a GtkCellRenderer from the area.
`foreach` () | calls the GtkCellCallback function on every GtkCellRenderer in the area with the provided user data until the callback returns `TRUE`.
`foreach_alloc` () | Calls the GtkCellAllocCallback function on every GtkCellRenderer in the area with the allocated area for the cell and the provided user data until the callback returns `TRUE`.
`event` () | Handle an event in the area, this is generally used to activate a cell at the event location for button events but can also be used to generically pass events to GtkWidgets drawn onto the area.
`render` () | Actually render the area's cells to the specified rectangle, `background_area` should be correctly distributed to the cells corresponding background areas.
`apply_attributes` () | Apply the cell attributes to the cells. This is implemented as a signal and generally GtkCellArea subclasses don't need to implement it since it is handled by the base class.
`create_context` () | Creates and returns a class specific GtkCellAreaContext to store cell alignment and allocation details for a said GtkCellArea class.
`copy_context` () | Creates a new GtkCellAreaContext in the same state as the passed `context` with any cell alignment data and allocations intact.
`get_request_mode` () | This allows an area to tell its layouting widget whether it prefers to be allocated in `GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH` or `GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT` mode.
`get_preferred_width` () | Calculates the minimum and natural width of the areas cells with the current attributes applied while considering the particular layouting details of the said GtkCellArea. While requests are performed over a series of rows, alignments and overall minimum and natural sizes should be stored in the corresponding GtkCellAreaContext.

`get_preferred_height_for_width` ()

Calculates the minimum and natural height for the area if the passed `context` would be allocated the given width. When implementing this virtual method it is safe to assume that `context` has already stored the aligned cell widths for every GtkTreeModel row that `context` will be allocated for since this information was stored at `GtkCellAreaClass.get_preferred_width()` time. This virtual method should also store any necessary alignments of cell heights for the case that the context is allocated a height.

`get_preferred_height` () | Calculates the minimum and natural height of the areas cells with the current attributes applied. Essentially this is the same as `GtkCellAreaClass.get_preferred_width()` only for areas that are being requested as `GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT`.
`get_preferred_width_for_height` () | Calculates the minimum and natural width for the area if the passed `context` would be allocated the given height. The same as `GtkCellAreaClass.get_preferred_height_for_width()` only for handling requests in the `GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT` mode.
`set_cell_property` () | This should be implemented to handle changes in child cell properties for a given GtkCellRenderer that were previously installed on the GtkCellAreaClass with `gtk_cell_area_class_install_cell_property()`.
`get_cell_property` () | This should be implemented to report the values of child cell properties for a given child GtkCellRenderer.

`focus` ()

This virtual method should be implemented to navigate focus from cell to cell inside the GtkCellArea. The GtkCellArea should move focus from cell to cell inside the area and return `FALSE` if focus logically leaves the area with the following exceptions: When the area contains no activatable cells, the entire area recieves focus. Focus should not be given to cells that are actually "focus siblings" of other sibling cells (see `gtk_cell_area_get_focus_from_sibling()`). Focus is set by calling `gtk_cell_area_set_focus_cell()`.

`is_activatable` () | Returns whether the GtkCellArea can respond to `GtkCellAreaClass.activate()`, usually this does not need to be implemented since the base class takes care of this however it can be enhanced if the GtkCellArea subclass can handle activation in other ways than activating its GtkCellRenderers.
`activate` () | This is called when the layouting widget rendering the GtkCellArea activates the focus cell (see `gtk_cell_area_get_focus_cell()`).

### GtkCellCallback ()

    gboolean            (*GtkCellCallback)                  (GtkCellRenderer *renderer,
                                                             gpointer data);

The type of the callback functions used for iterating over the cell renderers of a GtkCellArea, see `gtk_cell_area_foreach()`.

`renderer` : | the cell renderer to operate on
`data` : | user-supplied data. [closure]
Returns : | `TRUE` to stop iterating over cells.

### GtkCellAllocCallback ()

    gboolean            (*GtkCellAllocCallback)             (GtkCellRenderer *renderer,
                                                             const GdkRectangle *cell_area,
                                                             const GdkRectangle *cell_background,
                                                             gpointer data);

The type of the callback functions used for iterating over the cell renderers and their allocated areas inside a GtkCellArea, see `gtk_cell_area_foreach_alloc()`.

`renderer` : | the cell renderer to operate on
`cell_area` : | the area allocated to `renderer` inside the rectangle provided to `gtk_cell_area_foreach_alloc()`.
`cell_background` : | the background area for `renderer` inside the background area provided to `gtk_cell_area_foreach_alloc()`.
`data` : | user-supplied data. [closure]
Returns : | `TRUE` to stop iterating over cells.

### GTK_CELL_AREA_WARN_INVALID_CELL_PROPERTY_ID()

    #define             GTK_CELL_AREA_WARN_INVALID_CELL_PROPERTY_ID(object, property_id, pspec)

This macro should be used to emit a standard warning about unexpected properties in `set_cell_property()` and `get_cell_property()` implementations.

`object` : | the GObject on which `set_cell_property()` or `get_get_property()` was called
`property_id` : | the numeric id of the property
`pspec` : | the GParamSpec of the property

### gtk_cell_area_add ()

    void                gtk_cell_area_add                   (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);

Adds `renderer` to `area` with the default child cell properties.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer to add to `area`

Since 3.0

### gtk_cell_area_remove ()

    void                gtk_cell_area_remove                (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);

Removes `renderer` from `area`.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer to remove from `area`

Since 3.0

### gtk_cell_area_has_renderer ()

    gboolean            gtk_cell_area_has_renderer          (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);

Checks if `area` contains `renderer`.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer to check
Returns : | `TRUE` if `renderer` is in the `area`.

Since 3.0

### gtk_cell_area_foreach ()

    void                gtk_cell_area_foreach               (GtkCellArea *area,
                                                             GtkCellCallback callback,
                                                             gpointer callback_data);

Calls `callback` for every GtkCellRenderer in `area`.

`area` : | a GtkCellArea
`callback` : | the GtkCellCallback to call. [scope call]
`callback_data` : | user provided data pointer

Since 3.0

### gtk_cell_area_foreach_alloc ()

    void                gtk_cell_area_foreach_alloc         (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             const GdkRectangle *background_area,
                                                             GtkCellAllocCallback callback,
                                                             gpointer callback_data);

Calls `callback` for every GtkCellRenderer in `area` with the allocated rectangle inside `cell_area`.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext for this row of data.
`widget` : | the GtkWidget that `area` is rendering to
`cell_area` : | the `widget` relative coordinates and size for `area`
`background_area` : | the `widget` relative coordinates of the background area
`callback` : | the GtkCellAllocCallback to call. [scope call]
`callback_data` : | user provided data pointer

Since 3.0

### gtk_cell_area_event ()

    gint                gtk_cell_area_event                 (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             GdkEvent *event,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags);

Delegates event handling to a GtkCellArea.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext for this row of data.
`widget` : | the GtkWidget that `area` is rendering to
`event` : | the GdkEvent to handle
`cell_area` : | the `widget` relative coordinates for `area`
`flags` : | the GtkCellRendererState for `area` in this row.
Returns : | `TRUE` if the event was handled by `area`.

Since 3.0

### gtk_cell_area_render ()

    void                gtk_cell_area_render                (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             cairo_t *cr,
                                                             const GdkRectangle *background_area,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags,
                                                             gboolean paint_focus);

Renders `area`'s cells according to `area`'s layout onto `widget` at the given coordinates.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext for this row of data.
`widget` : | the GtkWidget that `area` is rendering to
`cr` : | the cairo_t to render with
`background_area` : | the `widget` relative coordinates for `area`'s background
`cell_area` : | the `widget` relative coordinates for `area`
`flags` : | the GtkCellRendererState for `area` in this row.
`paint_focus` : | whether `area` should paint focus on focused cells for focused rows or not.

Since 3.0

### gtk_cell_area_get_cell_allocation ()

    void                gtk_cell_area_get_cell_allocation   (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             GtkCellRenderer *renderer,
                                                             const GdkRectangle *cell_area,
                                                             GdkRectangle *allocation);

Derives the allocation of `renderer` inside `area` if `area` were to be renderered in `cell_area`.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext used to hold sizes for `area`.
`widget` : | the GtkWidget that `area` is rendering on
`renderer` : | the GtkCellRenderer to get the allocation for
`cell_area` : | the whole allocated area for `area` in `widget` for this row
`allocation` : | where to store the allocation for `renderer`. [out]

Since 3.0

### gtk_cell_area_get_cell_at_position ()

    GtkCellRenderer *   gtk_cell_area_get_cell_at_position  (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             gint x,
                                                             gint y,
                                                             GdkRectangle *alloc_area);

Gets the GtkCellRenderer at `x` and `y` coordinates inside `area` and optionally returns the full cell allocation for it inside `cell_area`.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext used to hold sizes for `area`.
`widget` : | the GtkWidget that `area` is rendering on
`cell_area` : | the whole allocated area for `area` in `widget` for this row
`x` : | the x position
`y` : | the y position
`alloc_area` : | where to store the inner allocated area of the returned cell renderer, or `NULL`. [out][allow-none]
Returns : | the GtkCellRenderer at `x` and `y`. [transfer none]

Since 3.0

### gtk_cell_area_create_context ()

    GtkCellAreaContext * gtk_cell_area_create_context       (GtkCellArea *area);

Creates a GtkCellAreaContext to be used with `area` for all purposes. GtkCellAreaContext stores geometry information for rows for which it was operated on, it is important to use the same context for the same row of data at all times (i.e. one should render and handle events with the same GtkCellAreaContext which was used to request the size of those rows of data).

`area` : | a GtkCellArea
Returns : | a newly created GtkCellAreaContext which can be used with `area`. [transfer full]

Since 3.0

### gtk_cell_area_copy_context ()

    GtkCellAreaContext * gtk_cell_area_copy_context         (GtkCellArea *area,
                                                             GtkCellAreaContext *context);

This is sometimes needed for cases where rows need to share alignments in one orientation but may be separately grouped in the opposing orientation.

For instance, GtkIconView creates all icons (rows) to have the same width and the cells theirin to have the same horizontal alignments. However each row of icons may have a separate collective height. GtkIconView uses this to request the heights of each row based on a context which was already used to request all the row widths that are to be displayed.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext to copy
Returns : | a newly created GtkCellAreaContext copy of `context`. [transfer full]

Since 3.0

### gtk_cell_area_get_request_mode ()

    GtkSizeRequestMode  gtk_cell_area_get_request_mode      (GtkCellArea *area);

Gets whether the area prefers a height-for-width layout or a width-for-height layout.

`area` : | a GtkCellArea
Returns : | The GtkSizeRequestMode preferred by `area`.

Since 3.0

### gtk_cell_area_get_preferred_width ()

    void                gtk_cell_area_get_preferred_width   (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint *minimum_width,
                                                             gint *natural_width);

Retrieves a cell area's initial minimum and natural width.

`area` will store some geometrical information in `context` along the way, when requesting sizes over an arbitrary number of rows, its not important to check the `minimum_width` and `natural_width` of this call but rather to consult `gtk_cell_area_context_get_preferred_width()` after a series of requests.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext to perform this request with
`widget` : | the GtkWidget where `area` will be rendering
`minimum_width` : | location to store the minimum width, or `NULL`. [out][allow-none]
`natural_width` : | location to store the natural width, or `NULL`. [out][allow-none]

Since 3.0

### gtk_cell_area_get_preferred_height_for_width ()

    void                gtk_cell_area_get_preferred_height_for_width
                                                            (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint width,
                                                             gint *minimum_height,
                                                             gint *natural_height);

Retrieves a cell area's minimum and natural height if it would be given the specified `width`.

`area` stores some geometrical information in `context` along the way while calling `gtk_cell_area_get_preferred_width()`. It's important to perform a series of `gtk_cell_area_get_preferred_width()` requests with `context` first and then call `gtk_cell_area_get_preferred_height_for_width()` on each cell area individually to get the height for width of each fully requested row.

If at some point, the width of a single row changes, it should be requested with `gtk_cell_area_get_preferred_width()` again and then the full width of the requested rows checked again with `gtk_cell_area_context_get_preferred_width()`.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext which has already been requested for widths.
`widget` : | the GtkWidget where `area` will be rendering
`width` : | the width for which to check the height of this area
`minimum_height` : | location to store the minimum height, or `NULL`. [out][allow-none]
`natural_height` : | location to store the natural height, or `NULL`. [out][allow-none]

Since 3.0

### gtk_cell_area_get_preferred_height ()

    void                gtk_cell_area_get_preferred_height  (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint *minimum_height,
                                                             gint *natural_height);

Retrieves a cell area's initial minimum and natural height.

`area` will store some geometrical information in `context` along the way, when requesting sizes over an arbitrary number of rows, its not important to check the `minimum_height` and `natural_height` of this call but rather to consult `gtk_cell_area_context_get_preferred_height()` after a series of requests.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext to perform this request with
`widget` : | the GtkWidget where `area` will be rendering
`minimum_height` : | location to store the minimum height, or `NULL`. [out][allow-none]
`natural_height` : | location to store the natural height, or `NULL`. [out][allow-none]

Since 3.0

### gtk_cell_area_get_preferred_width_for_height ()

    void                gtk_cell_area_get_preferred_width_for_height
                                                            (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             gint height,
                                                             gint *minimum_width,
                                                             gint *natural_width);

Retrieves a cell area's minimum and natural width if it would be given the specified `height`.

`area` stores some geometrical information in `context` along the way while calling `gtk_cell_area_get_preferred_height()`. It's important to perform a series of `gtk_cell_area_get_preferred_height()` requests with `context` first and then call `gtk_cell_area_get_preferred_width_for_height()` on each cell area individually to get the height for width of each fully requested row.

If at some point, the height of a single row changes, it should be requested with `gtk_cell_area_get_preferred_height()` again and then the full height of the requested rows checked again with `gtk_cell_area_context_get_preferred_height()`.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext which has already been requested for widths.
`widget` : | the GtkWidget where `area` will be rendering
`height` : | the height for which to check the width of this area
`minimum_width` : | location to store the minimum width, or `NULL`. [out][allow-none]
`natural_width` : | location to store the natural width, or `NULL`. [out][allow-none]

Since 3.0

### gtk_cell_area_get_current_path_string ()

    const gchar *       gtk_cell_area_get_current_path_string
                                                            (GtkCellArea *area);

Gets the current GtkTreePath string for the currently applied GtkTreeIter, this is implicitly updated when `gtk_cell_area_apply_attributes()` is called and can be used to interact with renderers from GtkCellArea subclasses.

`area` : | a GtkCellArea
Returns : | The current GtkTreePath string for the current attributes applied to `area`. This string belongs to the area and should not be freed.

Since 3.0

### gtk_cell_area_apply_attributes ()

    void                gtk_cell_area_apply_attributes      (GtkCellArea *area,
                                                             GtkTreeModel *tree_model,
                                                             GtkTreeIter *iter,
                                                             gboolean is_expander,
                                                             gboolean is_expanded);

Applies any connected attributes to the renderers in `area` by pulling the values from `tree_model`.

`area` : | a GtkCellArea
`tree_model` : | the GtkTreeModel to pull values from
`iter` : | the GtkTreeIter in `tree_model` to apply values for
`is_expander` : | whether `iter` has children
`is_expanded` : | whether `iter` is expanded in the view and children are visible

Since 3.0

### gtk_cell_area_attribute_connect ()

    void                gtk_cell_area_attribute_connect     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *attribute,
                                                             gint column);

Connects an `attribute` to apply values from `column` for the GtkTreeModel in use.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer to connect an attribute for
`attribute` : | the attribute name
`column` : | the GtkTreeModel column to fetch attribute values from

Since 3.0

### gtk_cell_area_attribute_disconnect ()

    void                gtk_cell_area_attribute_disconnect  (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *attribute);

Disconnects `attribute` for the `renderer` in `area` so that attribute will no longer be updated with values from the model.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer to disconnect an attribute for
`attribute` : | the attribute name

Since 3.0

### gtk_cell_area_class_install_cell_property ()

    void                gtk_cell_area_class_install_cell_property
                                                            (GtkCellAreaClass *aclass,
                                                             guint property_id,
                                                             GParamSpec *pspec);

Installs a cell property on a cell area class.

`aclass` : | a GtkCellAreaClass
`property_id` : | the id for the property
`pspec` : | the GParamSpec for the property

Since 3.0

### gtk_cell_area_class_find_cell_property ()

    GParamSpec *        gtk_cell_area_class_find_cell_property
                                                            (GtkCellAreaClass *aclass,
                                                             const gchar *property_name);

Finds a cell property of a cell area class by name.

`aclass` : | a GtkCellAreaClass
`property_name` : | the name of the child property to find
Returns : | the GParamSpec of the child property or `NULL` if `aclass` has no child property with that name. [transfer none]

Since 3.0

### gtk_cell_area_class_list_cell_properties ()

    GParamSpec **       gtk_cell_area_class_list_cell_properties
                                                            (GtkCellAreaClass *aclass,
                                                             guint *n_properties);

Returns all cell properties of a cell area class.

`aclass` : | a GtkCellAreaClass
`n_properties` : | location to return the number of cell properties found
Returns : | a newly allocated `NULL`-terminated array of GParamSpec*. The array must be freed with `g_free()`. [array length=n_properties][transfer container]

Since 3.0

### gtk_cell_area_add_with_properties ()

    void                gtk_cell_area_add_with_properties   (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_prop_name,
                                                             ...);

Adds `renderer` to `area`, setting cell properties at the same time. See `gtk_cell_area_add()` and `gtk_cell_area_cell_set()` for more details.

`area` : | a GtkCellArea
`renderer` : | a GtkCellRenderer to be placed inside `area`
`first_prop_name` : | the name of the first cell property to set
`Varargs` : | a `NULL`-terminated list of property names and values, starting with `first_prop_name`

Since 3.0

### gtk_cell_area_cell_set ()

    void                gtk_cell_area_cell_set              (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_prop_name,
                                                             ...);

Sets one or more cell properties for `cell` in `area`.

`area` : | a GtkCellArea
`renderer` : | a GtkCellRenderer which is a cell inside `area`
`first_prop_name` : | the name of the first cell property to set
`Varargs` : | a `NULL`-terminated list of property names and values, starting with `first_prop_name`

Since 3.0

### gtk_cell_area_cell_get ()

    void                gtk_cell_area_cell_get              (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_prop_name,
                                                             ...);

Gets the values of one or more cell properties for `renderer` in `area`.

`area` : | a GtkCellArea
`renderer` : | a GtkCellRenderer which is inside `area`
`first_prop_name` : | the name of the first cell property to get
`Varargs` : | return location for the first cell property, followed optionally by more name/return location pairs, followed by `NULL`

Since 3.0

### gtk_cell_area_cell_set_valist ()

    void                gtk_cell_area_cell_set_valist       (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_property_name,
                                                             va_list var_args);

Sets one or more cell properties for `renderer` in `area`.

`area` : | a GtkCellArea
`renderer` : | a GtkCellRenderer which inside `area`
`first_property_name` : | the name of the first cell property to set
`var_args` : | a `NULL`-terminated list of property names and values, starting with `first_prop_name`

Since 3.0

### gtk_cell_area_cell_get_valist ()

    void                gtk_cell_area_cell_get_valist       (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *first_property_name,
                                                             va_list var_args);

Gets the values of one or more cell properties for `renderer` in `area`.

`area` : | a GtkCellArea
`renderer` : | a GtkCellRenderer inside `area`
`first_property_name` : | the name of the first property to get
`var_args` : | return location for the first property, followed optionally by more name/return location pairs, followed by `NULL`

Since 3.0

### gtk_cell_area_cell_set_property ()

    void                gtk_cell_area_cell_set_property     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *property_name,
                                                             const GValue *value);

Sets a cell property for `renderer` in `area`.

`area` : | a GtkCellArea
`renderer` : | a GtkCellRenderer inside `area`
`property_name` : | the name of the cell property to set
`value` : | the value to set the cell property to

Since 3.0

### gtk_cell_area_cell_get_property ()

    void                gtk_cell_area_cell_get_property     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             const gchar *property_name,
                                                             GValue *value);

Gets the value of a cell property for `renderer` in `area`.

`area` : | a GtkCellArea
`renderer` : | a GtkCellRenderer inside `area`
`property_name` : | the name of the property to get
`value` : | a location to return the value

Since 3.0

### gtk_cell_area_is_activatable ()

    gboolean            gtk_cell_area_is_activatable        (GtkCellArea *area);

Returns whether the area can do anything when activated, after applying new attributes to `area`.

`area` : | a GtkCellArea
Returns : | whether `area` can do anything when activated.

Since 3.0

### gtk_cell_area_activate ()

    gboolean            gtk_cell_area_activate              (GtkCellArea *area,
                                                             GtkCellAreaContext *context,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags,
                                                             gboolean edit_only);

Activates `area`, usually by activating the currently focused cell, however some subclasses which embed widgets in the area can also activate a widget if it currently has the focus.

`area` : | a GtkCellArea
`context` : | the GtkCellAreaContext in context with the current row data
`widget` : | the GtkWidget that `area` is rendering on
`cell_area` : | the size and location of `area` relative to `widget`'s allocation
`flags` : | the GtkCellRendererState flags for `area` for this row of data.
`edit_only` : | if `TRUE` then only cell renderers that are `GTK_CELL_RENDERER_MODE_EDITABLE` will be activated.
Returns : | Whether `area` was successfully activated.

Since 3.0

### gtk_cell_area_focus ()

    gboolean            gtk_cell_area_focus                 (GtkCellArea *area,
                                                             GtkDirectionType direction);

This should be called by the `area`'s owning layout widget when focus is to be passed to `area`, or moved within `area` for a given `direction` and row data.

Implementing GtkCellArea classes should implement this method to receive and navigate focus in its own way particular to how it lays out cells.

`area` : | a GtkCellArea
`direction` : | the GtkDirectionType
Returns : | `TRUE` if focus remains inside `area` as a result of this call.

Since 3.0

### gtk_cell_area_set_focus_cell ()

    void                gtk_cell_area_set_focus_cell        (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);

Explicitly sets the currently focused cell to `renderer`.

This is generally called by implementations of `GtkCellAreaClass.focus()` or `GtkCellAreaClass.event()`, however it can also be used to implement functions such as `gtk_tree_view_set_cursor_on_cell()`.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer to give focus to

Since 3.0

### gtk_cell_area_get_focus_cell ()

    GtkCellRenderer *   gtk_cell_area_get_focus_cell        (GtkCellArea *area);

Retrieves the currently focused cell for `area`

`area` : | a GtkCellArea
Returns : | the currently focused cell in `area`. [transfer none]

Since 3.0

### gtk_cell_area_add_focus_sibling ()

    void                gtk_cell_area_add_focus_sibling     (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkCellRenderer *sibling);

Adds `sibling` to `renderer`'s focusable area, focus will be drawn around `renderer` and all of its siblings if `renderer` can focus for a given row.

Events handled by focus siblings can also activate the given focusable `renderer`.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer expected to have focus
`sibling` : | the GtkCellRenderer to add to `renderer`'s focus area

Since 3.0

### gtk_cell_area_remove_focus_sibling ()

    void                gtk_cell_area_remove_focus_sibling  (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkCellRenderer *sibling);

Removes `sibling` from `renderer`'s focus sibling list (see `gtk_cell_area_add_focus_sibling()`).

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer expected to have focus
`sibling` : | the GtkCellRenderer to remove from `renderer`'s focus area

Since 3.0

### gtk_cell_area_is_focus_sibling ()

    gboolean            gtk_cell_area_is_focus_sibling      (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkCellRenderer *sibling);

Returns whether `sibling` is one of `renderer`'s focus siblings (see `gtk_cell_area_add_focus_sibling()`).

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer expected to have focus
`sibling` : | the GtkCellRenderer to check against `renderer`'s sibling list
Returns : | `TRUE` if `sibling` is a focus sibling of `renderer`

Since 3.0

### gtk_cell_area_get_focus_siblings ()

    const GList *       gtk_cell_area_get_focus_siblings    (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);

Gets the focus sibling cell renderers for `renderer`.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer expected to have focus
Returns : | A GList of GtkCellRenderers. The returned list is internal and should not be freed. [element-type GtkCellRenderer][transfer none]

Since 3.0

### gtk_cell_area_get_focus_from_sibling ()

    GtkCellRenderer *   gtk_cell_area_get_focus_from_sibling
                                                            (GtkCellArea *area,
                                                             GtkCellRenderer *renderer);

Gets the GtkCellRenderer which is expected to be focusable for which `renderer` is, or may be a sibling.

This is handy for GtkCellArea subclasses when handling events, after determining the renderer at the event location it can then chose to activate the focus cell for which the event cell may have been a sibling.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer
Returns : | the GtkCellRenderer for which `renderer` is a sibling, or `NULL`. [transfer none]

Since 3.0

### gtk_cell_area_get_edited_cell ()

    GtkCellRenderer *   gtk_cell_area_get_edited_cell       (GtkCellArea *area);

Gets the GtkCellRenderer in `area` that is currently being edited.

`area` : | a GtkCellArea
Returns : | The currently edited GtkCellRenderer. [transfer none]

Since 3.0

### gtk_cell_area_get_edit_widget ()

    GtkCellEditable *   gtk_cell_area_get_edit_widget       (GtkCellArea *area);

Gets the GtkCellEditable widget currently used to edit the currently edited cell.

`area` : | a GtkCellArea
Returns : | The currently active GtkCellEditable widget. [transfer none]

Since 3.0

### gtk_cell_area_activate_cell ()

    gboolean            gtk_cell_area_activate_cell         (GtkCellArea *area,
                                                             GtkWidget *widget,
                                                             GtkCellRenderer *renderer,
                                                             GdkEvent *event,
                                                             const GdkRectangle *cell_area,
                                                             GtkCellRendererState flags);

This is used by GtkCellArea subclasses when handling events to activate cells, the base GtkCellArea class activates cells for keyboard events for free in its own GtkCellArea->`activate()` implementation.

`area` : | a GtkCellArea
`widget` : | the GtkWidget that `area` is rendering onto
`renderer` : | the GtkCellRenderer in `area` to activate
`event` : | the GdkEvent for which cell activation should occur
`cell_area` : | the GdkRectangle in `widget` relative coordinates of `renderer` for the current row.
`flags` : | the GtkCellRendererState for `renderer`
Returns : | whether cell activation was successful

Since 3.0

### gtk_cell_area_stop_editing ()

    void                gtk_cell_area_stop_editing          (GtkCellArea *area,
                                                             gboolean canceled);

Explicitly stops the editing of the currently edited cell (see `gtk_cell_area_get_edited_cell()`).

If `canceled` is `TRUE`, the cell renderer will emit the ::editing-canceled signal.

`area` : | a GtkCellArea
`canceled` : | whether editing was canceled.

Since 3.0

### gtk_cell_area_inner_cell_area ()

    void                gtk_cell_area_inner_cell_area       (GtkCellArea *area,
                                                             GtkWidget *widget,
                                                             const GdkRectangle *cell_area,
                                                             GdkRectangle *inner_area);

This is a convenience function for GtkCellArea implementations to get the inner area where a given GtkCellRenderer will be rendered. It removes any padding previously added by `gtk_cell_area_request_renderer()`.

`area` : | a GtkCellArea
`widget` : | the GtkWidget that `area` is rendering onto
`cell_area` : | the `widget` relative coordinates where one of `area`'s cells is to be placed
`inner_area` : | the return location for the inner cell area. [out]

Since 3.0

### gtk_cell_area_request_renderer ()

    void                gtk_cell_area_request_renderer      (GtkCellArea *area,
                                                             GtkCellRenderer *renderer,
                                                             GtkOrientation orientation,
                                                             GtkWidget *widget,
                                                             gint for_size,
                                                             gint *minimum_size,
                                                             gint *natural_size);

This is a convenience function for GtkCellArea implementations to request size for cell renderers. It's important to use this function to request size and then use `gtk_cell_area_inner_cell_area()` at render and event time since this function will add padding around the cell for focus painting.

`area` : | a GtkCellArea
`renderer` : | the GtkCellRenderer to request size for
`orientation` : | the GtkOrientation in which to request size
`widget` : | the GtkWidget that `area` is rendering onto
`for_size` : | the allocation contextual size to request for, or -1 if the base request for the orientation is to be returned.
`minimum_size` : | location to store the minimum size, or `NULL`. [out][allow-none]
`natural_size` : | location to store the natural size, or `NULL`. [out][allow-none]

Since 3.0

## Property Details

### The `"edit-widget"` property

      "edit-widget"              GtkCellEditable*      : Read

The widget currently editing the edited cell

This property is read-only and only changes as a result of a call `gtk_cell_area_activate_cell()`.

Since 3.0

### The `"edited-cell"` property

      "edited-cell"              GtkCellRenderer*      : Read

The cell in the area that is currently edited

This property is read-only and only changes as a result of a call `gtk_cell_area_activate_cell()`.

Since 3.0

### The `"focus-cell"` property

      "focus-cell"               GtkCellRenderer*      : Read / Write

The cell in the area that currently has focus

Since 3.0

## Signal Details

### The `"add-editable"` signal

    void                user_function                      (GtkCellArea     *area,
                                                            GtkCellRenderer *renderer,
                                                            GtkCellEditable *editable,
                                                            GdkRectangle    *cell_area,
                                                            gchar           *path,
                                                            gpointer         user_data)      : Run First

Indicates that editing has started on `renderer` and that `editable` should be added to the owning cell-layouting widget at `cell_area`.

`area` : | the GtkCellArea where editing started
`renderer` : | the GtkCellRenderer that started the edited
`editable` : | the GtkCellEditable widget to add
`cell_area` : | the GtkWidget relative GdkRectangle coordinates where `editable` should be added
`path` : | the GtkTreePath string this edit was initiated for
`user_data` : | user data set when the signal handler was connected.

Since 3.0

### The `"apply-attributes"` signal

    void                user_function                      (GtkCellArea  *area,
                                                            GtkTreeModel *model,
                                                            GtkTreeIter  *iter,
                                                            gboolean      is_expander,
                                                            gboolean      is_expanded,
                                                            gpointer      user_data)        : Run First

This signal is emitted whenever applying attributes to `area` from `model`

`area` : | the GtkCellArea to apply the attributes to
`model` : | the GtkTreeModel to apply the attributes from
`iter` : | the GtkTreeIter indicating which row to apply the attributes of
`is_expander` : | whether the view shows children for this row
`is_expanded` : | whether the view is currently showing the children of this row
`user_data` : | user data set when the signal handler was connected.

Since 3.0

### The `"focus-changed"` signal

    void                user_function                      (GtkCellArea     *area,
                                                            GtkCellRenderer *renderer,
                                                            gchar           *path,
                                                            gpointer         user_data)      : Run First

Indicates that focus changed on this `area`. This signal is emitted either as a result of focus handling or event handling.

It's possible that the signal is emitted even if the currently focused renderer did not change, this is because focus may change to the same renderer in the same cell area for a different row of data.

`area` : | the GtkCellArea where focus changed
`renderer` : | the GtkCellRenderer that has focus
`path` : | the current GtkTreePath string set for `area`
`user_data` : | user data set when the signal handler was connected.

Since 3.0

### The `"remove-editable"` signal

    void                user_function                      (GtkCellArea     *area,
                                                            GtkCellRenderer *renderer,
                                                            GtkCellEditable *editable,
                                                            gpointer         user_data)      : Run First

Indicates that editing finished on `renderer` and that `editable` should be removed from the owning cell-layouting widget.

`area` : | the GtkCellArea where editing finished
`renderer` : | the GtkCellRenderer that finished editeding
`editable` : | the GtkCellEditable widget to remove
`user_data` : | user data set when the signal handler was connected.

Since 3.0