GtkCellAreaContext

gtk_cell_area_context_get_area ()

GtkCellArea *
gtk_cell_area_context_get_area (GtkCellAreaContext *context);

Fetches the GtkCellArea this context was created by.

This is generally unneeded by layouting widgets; however, it is important for the context implementation itself to fetch information about the area it is being used for.

For instance at GtkCellAreaContextClass.allocate() time it’s important to know details about any cell spacing that the GtkCellArea is configured with in order to compute a proper allocation.

Since: 3.0

gtk_cell_area_context_allocate ()

void
gtk_cell_area_context_allocate (GtkCellAreaContext *context,
                                gint width,
                                gint height);

Allocates a width and/or a height for all rows which are to be rendered with context .

Usually allocation is performed only horizontally or sometimes vertically since a group of rows are usually rendered side by side vertically or horizontally and share either the same width or the same height. Sometimes they are allocated in both horizontal and vertical orientations producing a homogeneous effect of the rows. This is generally the case for GtkTreeView when “fixed-height-mode” is enabled.

Since 3.0

gtk_cell_area_context_reset ()

void
gtk_cell_area_context_reset (GtkCellAreaContext *context);

Resets any previously cached request and allocation data.

When underlying GtkTreeModel data changes its important to reset the context if the content size is allowed to shrink. If the content size is only allowed to grow (this is usually an option for views rendering large data stores as a measure of optimization), then only the row that changed or was inserted needs to be (re)requested with gtk_cell_area_get_preferred_width().

When the new overall size of the context requires that the allocated size changes (or whenever this allocation changes at all), the variable row sizes need to be re-requested for every row.

For instance, if the rows are displayed all with the same width from top to bottom then a change in the allocated width necessitates a recalculation of all the displayed row heights using gtk_cell_area_get_preferred_height_for_width().

Since 3.0

gtk_cell_area_context_get_preferred_width ()

void
gtk_cell_area_context_get_preferred_width
                               (GtkCellAreaContext *context,
                                gint *minimum_width,
                                gint *natural_width);

Gets the accumulative preferred width for all rows which have been requested with this context.

After gtk_cell_area_context_reset() is called and/or before ever requesting the size of a GtkCellArea, the returned values are 0.

Since: 3.0

gtk_cell_area_context_get_preferred_height ()

void
gtk_cell_area_context_get_preferred_height
                               (GtkCellAreaContext *context,
                                gint *minimum_height,
                                gint *natural_height);

Gets the accumulative preferred height for all rows which have been requested with this context.

After gtk_cell_area_context_reset() is called and/or before ever requesting the size of a GtkCellArea, the returned values are 0.

Since: 3.0

gtk_cell_area_context_get_preferred_height_for_width ()

void
gtk_cell_area_context_get_preferred_height_for_width
                               (GtkCellAreaContext *context,
                                gint width,
                                gint *minimum_height,
                                gint *natural_height);

Gets the accumulative preferred height for width for all rows which have been requested for the same said width with this context.

After gtk_cell_area_context_reset() is called and/or before ever requesting the size of a GtkCellArea, the returned values are -1.

Since: 3.0

gtk_cell_area_context_get_preferred_width_for_height ()

void
gtk_cell_area_context_get_preferred_width_for_height
                               (GtkCellAreaContext *context,
                                gint height,
                                gint *minimum_width,
                                gint *natural_width);

Gets the accumulative preferred width for height for all rows which have been requested for the same said height with this context.

After gtk_cell_area_context_reset() is called and/or before ever requesting the size of a GtkCellArea, the returned values are -1.

Since: 3.0

gtk_cell_area_context_get_allocation ()

void
gtk_cell_area_context_get_allocation (GtkCellAreaContext *context,
                                      gint *width,
                                      gint *height);

Fetches the current allocation size for context .

If the context was not allocated in width or height, or if the context was recently reset with gtk_cell_area_context_reset(), the returned value will be -1.

Since: 3.0

gtk_cell_area_context_push_preferred_width ()

void
gtk_cell_area_context_push_preferred_width
                               (GtkCellAreaContext *context,
                                gint minimum_width,
                                gint natural_width);

Causes the minimum and/or natural width to grow if the new proposed sizes exceed the current minimum and natural width.

This is used by GtkCellAreaContext implementations during the request process over a series of GtkTreeModel rows to progressively push the requested width over a series of gtk_cell_area_get_preferred_width() requests.

Since: 3.0

gtk_cell_area_context_push_preferred_height ()

void
gtk_cell_area_context_push_preferred_height
                               (GtkCellAreaContext *context,
                                gint minimum_height,
                                gint natural_height);

Causes the minimum and/or natural height to grow if the new proposed sizes exceed the current minimum and natural height.

This is used by GtkCellAreaContext implementations during the request process over a series of GtkTreeModel rows to progressively push the requested height over a series of gtk_cell_area_get_preferred_height() requests.

Since: 3.0

struct GtkCellAreaContextClass

struct GtkCellAreaContextClass {
  void    (* allocate)                       (GtkCellAreaContext *context,
                                              gint                width,
                                              gint                height);
  void    (* reset)                          (GtkCellAreaContext *context);
  void    (* get_preferred_height_for_width) (GtkCellAreaContext *context,
                                              gint                width,
                                              gint               *minimum_height,
                                              gint               *natural_height);
  void    (* get_preferred_width_for_height) (GtkCellAreaContext *context,
                                              gint                height,
                                              gint               *minimum_width,
                                              gint               *natural_width);
};

GtkCellAreaContext

typedef struct _GtkCellAreaContext GtkCellAreaContext;

The “area” property

  “area”                     GtkCellArea *

The GtkCellArea this context was created by

Owner: GtkCellAreaContext

Flags: Read / Write / Construct Only

Since: 3.0

The “minimum-height” property

  “minimum-height”           int

The minimum height for the GtkCellArea in this context for all GtkTreeModel rows that this context was requested for using gtk_cell_area_get_preferred_height().

Owner: GtkCellAreaContext

Flags: Read

Allowed values: >= -1

Default value: -1

Since: 3.0

The “minimum-width” property

  “minimum-width”            int

The minimum width for the GtkCellArea in this context for all GtkTreeModel rows that this context was requested for using gtk_cell_area_get_preferred_width().

Owner: GtkCellAreaContext

Flags: Read

Allowed values: >= -1

Default value: -1

Since: 3.0

The “natural-height” property

  “natural-height”           int

The natural height for the GtkCellArea in this context for all GtkTreeModel rows that this context was requested for using gtk_cell_area_get_preferred_height().

Owner: GtkCellAreaContext

Flags: Read

Allowed values: >= -1

Default value: -1

Since: 3.0

The “natural-width” property

  “natural-width”            int

The natural width for the GtkCellArea in this context for all GtkTreeModel rows that this context was requested for using gtk_cell_area_get_preferred_width().

Owner: GtkCellAreaContext

Flags: Read

Allowed values: >= -1

Default value: -1

Since: 3.0