GtkCellArea

GtkCellArea — An abstract class for laying out GtkCellRenderers

Functions

gboolean (*GtkCellCallback) ()
gboolean (*GtkCellAllocCallback) ()
#define GTK_CELL_AREA_WARN_INVALID_CELL_PROPERTY_ID()
void gtk_cell_area_add ()
void gtk_cell_area_remove ()
gboolean gtk_cell_area_has_renderer ()
void gtk_cell_area_foreach ()
void gtk_cell_area_foreach_alloc ()
gint gtk_cell_area_event ()
void gtk_cell_area_render ()
void gtk_cell_area_get_cell_allocation ()
GtkCellRenderer * gtk_cell_area_get_cell_at_position ()
GtkCellAreaContext * gtk_cell_area_create_context ()
GtkCellAreaContext * gtk_cell_area_copy_context ()
GtkSizeRequestMode gtk_cell_area_get_request_mode ()
void gtk_cell_area_get_preferred_width ()
void gtk_cell_area_get_preferred_height_for_width ()
void gtk_cell_area_get_preferred_height ()
void gtk_cell_area_get_preferred_width_for_height ()
const gchar * gtk_cell_area_get_current_path_string ()
void gtk_cell_area_apply_attributes ()
void gtk_cell_area_attribute_connect ()
void gtk_cell_area_attribute_disconnect ()
gint gtk_cell_area_attribute_get_column ()
void gtk_cell_area_class_install_cell_property ()
GParamSpec * gtk_cell_area_class_find_cell_property ()
GParamSpec ** gtk_cell_area_class_list_cell_properties ()
void gtk_cell_area_add_with_properties ()
void gtk_cell_area_cell_set ()
void gtk_cell_area_cell_get ()
void gtk_cell_area_cell_set_valist ()
void gtk_cell_area_cell_get_valist ()
void gtk_cell_area_cell_set_property ()
void gtk_cell_area_cell_get_property ()
gboolean gtk_cell_area_is_activatable ()
gboolean gtk_cell_area_activate ()
gboolean gtk_cell_area_focus ()
void gtk_cell_area_set_focus_cell ()
GtkCellRenderer * gtk_cell_area_get_focus_cell ()
void gtk_cell_area_add_focus_sibling ()
void gtk_cell_area_remove_focus_sibling ()
gboolean gtk_cell_area_is_focus_sibling ()
const GList * gtk_cell_area_get_focus_siblings ()
GtkCellRenderer * gtk_cell_area_get_focus_from_sibling ()
GtkCellRenderer * gtk_cell_area_get_edited_cell ()
GtkCellEditable * gtk_cell_area_get_edit_widget ()
gboolean gtk_cell_area_activate_cell ()
void gtk_cell_area_stop_editing ()
void gtk_cell_area_inner_cell_area ()
void gtk_cell_area_request_renderer ()

Signals

void add-editable Run First
void apply-attributes Run First
void focus-changed Run First
void remove-editable Run First

Types and Values

Object Hierarchy

    GObject
    ╰── GInitiallyUnowned
        ╰── GtkCellArea
            ╰── GtkCellAreaBox

Implemented Interfaces

GtkCellArea implements GtkCellLayout and GtkBuildable.

Includes

#include <gtk/gtk.h>

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:

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:

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:

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 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:

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:

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 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().

Functions

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().

Parameters

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().

Parameters

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.

Parameters

object

the GObject on which set_cell_property() or get_cell_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.

Parameters

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 .

Parameters

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 .

Parameters

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 .

Parameters

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 .

Parameters

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.

Parameters

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.

Parameters

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 .

Parameters

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 .

Parameters

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).

Parameters

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.

Parameters

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.

Parameters

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, it’s 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.

Parameters

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().

Parameters

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, it’s 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.

Parameters

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().

Parameters

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.

Parameters

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 .

Parameters

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.

Parameters

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.

Parameters

area

a GtkCellArea

renderer

the GtkCellRenderer to disconnect an attribute for

attribute

the attribute name

Since: 3.0

gtk_cell_area_attribute_get_column ()

gint
gtk_cell_area_attribute_get_column (GtkCellArea *area,
                                    GtkCellRenderer *renderer,
                                    const gchar *attribute);

Returns the model column that an attribute has been mapped to, or -1 if the attribute is not mapped.

Parameters

area

a GtkCellArea

renderer

a GtkCellRenderer

attribute

an attribute on the renderer

Returns

the model column, or -1

Since: 3.14

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.

Parameters

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.

Parameters

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.

Parameters

aclass

a GtkCellAreaClass

n_properties

location to return the number of cell properties found.

[out]

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.

Parameters

area

a GtkCellArea

renderer

a GtkCellRenderer to be placed inside area

first_prop_name

the name of the first cell property to set

...

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 .

Parameters

area

a GtkCellArea

renderer

a GtkCellRenderer which is a cell inside area

first_prop_name

the name of the first cell property to set

...

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 .

Parameters

area

a GtkCellArea

renderer

a GtkCellRenderer which is inside area

first_prop_name

the name of the first cell property to get

...

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 .

Parameters

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 .

Parameters

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 .

Parameters

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 .

Parameters

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 .

Parameters

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.

Parameters

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.

Parameters

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().

Parameters

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

Parameters

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 .

Parameters

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()).

Parameters

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()).

Parameters

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 .

Parameters

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.

Parameters

area

a GtkCellArea

renderer

the GtkCellRenderer

Returns

the GtkCellRenderer for which renderer is a sibling, or NULL.

[nullable][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.

Parameters

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.

Parameters

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.

Parameters

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.

If canceled is TRUE, the currently edited cell renderer will emit the ::editing-canceled signal, otherwise the the ::editing-done signal will be emitted on the current edit widget.

See gtk_cell_area_get_edited_cell() and gtk_cell_area_get_edit_widget().

Parameters

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().

Parameters

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.

Parameters

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

Types and Values

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);
};

Members

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()).

Property Details

The “edit-widget” property

  “edit-widget”              GtkCellEditable *

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().

Owner: GtkCellArea

Flags: Read

Since: 3.0

The “edited-cell” property

  “edited-cell”              GtkCellRenderer *

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().

Owner: GtkCellArea

Flags: Read

Since: 3.0

The “focus-cell” property

  “focus-cell”               GtkCellRenderer *

The cell in the area that currently has focus

Owner: GtkCellArea

Flags: Read / Write

Since: 3.0

Signal Details

The “add-editable” signal

void
user_function (GtkCellArea     *area,
               GtkCellRenderer *renderer,
               GtkCellEditable *editable,
               GdkRectangle    *cell_area,
               char            *path,
               gpointer         user_data)

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

Parameters

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.

Flags: Run First

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)

This signal is emitted whenever applying attributes to area from model

Parameters

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.

Flags: Run First

Since: 3.0

The “focus-changed” signal

void
user_function (GtkCellArea     *area,
               GtkCellRenderer *renderer,
               char            *path,
               gpointer         user_data)

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.

Parameters

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.

Flags: Run First

Since: 3.0

The “remove-editable” signal

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

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

Parameters

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.

Flags: Run First

Since: 3.0

© 2005–2020 The GNOME Project
Licensed under the GNU Lesser General Public License version 2.1 or later.
https://developer.gnome.org/gtk3/3.24/GtkCellArea.html