Gtk.CellAreaContext¶

Subclasses:: None

Methods¶

Inherited:: GObject.Object (37)
Structs:: GObject.ObjectClass (5)

	`allocate` (width, height)
	`get_allocation` ()
	`get_area` ()
	`get_preferred_height` ()
	`get_preferred_height_for_width` (width)
	`get_preferred_width` ()
	`get_preferred_width_for_height` (height)
	`push_preferred_height` (minimum_height, natural_height)
	`push_preferred_width` (minimum_width, natural_width)
	`reset` ()

Virtual Methods¶

Inherited:: GObject.Object (7)

	`do_allocate` (width, height)
	`do_get_preferred_height_for_width` (width)
	`do_get_preferred_width_for_height` (height)
	`do_reset` ()

Properties¶

Name	Type	Flags	Short Description
`area`	`Gtk.CellArea`	r/w/co	`deprecated`
`minimum-height`	`int`	r	`deprecated`
`minimum-width`	`int`	r	`deprecated`
`natural-height`	`int`	r	`deprecated`
`natural-width`	`int`	r	`deprecated`

Signals¶

Inherited:: GObject.Object (1)

Fields¶

Inherited:: GObject.Object (1)

Name	Type	Access	Description
parent_instance	`GObject.Object`	r

Class Details¶

class Gtk.CellAreaContext(**kwargs)¶

Bases:: GObject.Object
Abstract:: No
Structure:: Gtk.CellAreaContextClass

Stores geometrical information for a series of rows in a Gtk.CellArea

The GtkCellAreaContext object is created by a given GtkCellArea implementation via its GtkCellAreaClass.create_context() virtual method and is used to store cell sizes and alignments for a series of GtkTreeModel rows that are requested and rendered in the same context.

GtkCellLayout widgets can create any number of contexts in which to request and render groups of data rows. However, it’s important that the same context which was used to request sizes for a given GtkTreeModel row also be used for the same row when calling other GtkCellArea APIs such as gtk_cell_area_render() and Gtk.CellArea.event().

Deprecated since version 4.10: This object will be removed in GTK 5

allocate(width, height)[source]¶

Parameters:

width (int) – the allocated width for all GtkTreeModel rows rendered with self, or -1
height (int) – the allocated height for all GtkTreeModel rows rendered with self, or -1

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

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 GtkTreeView:fixed-height-mode is enabled.

Deprecated since version 4.10: This object will be removed in GTK 5

get_allocation()[source]¶

Returns:

width:: location to store the allocated width
height:: location to store the allocated height

Return type:

(width: int, height: int)

Fetches the current allocation size for self.

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

Deprecated since version 4.10: This object will be removed in GTK 5

get_area()[source]¶

Returns:: the GtkCellArea this context was created by.
Return type:: Gtk.CellArea

Fetches the GtkCellArea this self 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.

Deprecated since version 4.10: This object will be removed in GTK 5

get_preferred_height()[source]¶

Returns:

minimum_height:: location to store the minimum height
natural_height:: location to store the natural height

Return type:

(minimum_height: int, natural_height: int)

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

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

Deprecated since version 4.10: This object will be removed in GTK 5

get_preferred_height_for_width(width)[source]¶

Parameters:

width (int) – a proposed width for allocation

Returns:

minimum_height:: location to store the minimum height
natural_height:: location to store the natural height

Return type:

(minimum_height: int, natural_height: int)

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

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

Deprecated since version 4.10: This object will be removed in GTK 5

get_preferred_width()[source]¶

Returns:

minimum_width:: location to store the minimum width
natural_width:: location to store the natural width

Return type:

(minimum_width: int, natural_width: int)

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

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

Deprecated since version 4.10: This object will be removed in GTK 5

get_preferred_width_for_height(height)[source]¶

Parameters:

height (int) – a proposed height for allocation

Returns:

minimum_width:: location to store the minimum width
natural_width:: location to store the natural width

Return type:

(minimum_width: int, natural_width: int)

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

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

Deprecated since version 4.10: This object will be removed in GTK 5

push_preferred_height(minimum_height, natural_height)[source]¶

Parameters:

minimum_height (int) – the proposed new minimum height for self
natural_height (int) – the proposed new natural height for self

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.CellArea.get_preferred_height() requests.

Deprecated since version 4.10: This object will be removed in GTK 5

push_preferred_width(minimum_width, natural_width)[source]¶

Parameters:

minimum_width (int) – the proposed new minimum width for self
natural_width (int) – the proposed new natural width for self

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.CellArea.get_preferred_width() requests.

Deprecated since version 4.10: This object will be removed in GTK 5

reset()[source]¶

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.CellArea.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.CellArea.get_preferred_height_for_width().

Deprecated since version 4.10: This object will be removed in GTK 5

do_allocate(width, height) virtual¶

Parameters:

width (int) – the allocated width for all GtkTreeModel rows rendered with context, or -1
height (int) – the allocated height for all GtkTreeModel rows rendered with context, or -1

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 GtkTreeView:fixed-height-mode is enabled.

Deprecated since version 4.10: This object will be removed in GTK 5

do_get_preferred_height_for_width(width) virtual¶

Parameters:

width (int) – a proposed width for allocation

Returns:

minimum_height:: location to store the minimum height
natural_height:: location to store the natural height

Return type:

(minimum_height: int, natural_height: int)

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

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

Deprecated since version 4.10: This object will be removed in GTK 5

do_get_preferred_width_for_height(height) virtual¶

Parameters:

height (int) – a proposed height for allocation

Returns:

minimum_width:: location to store the minimum width
natural_width:: location to store the natural width

Return type:

(minimum_width: int, natural_width: int)

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

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

Deprecated since version 4.10: This object will be removed in GTK 5

do_reset() virtual¶

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.CellArea.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.CellArea.get_preferred_height_for_width().

Deprecated since version 4.10: This object will be removed in GTK 5

Property Details¶

Gtk.CellAreaContext.props.area¶

Name:: area
Type:: Gtk.CellArea
Default Value:: None
Flags:: READABLE, WRITABLE, CONSTRUCT_ONLY

The GtkCellArea this context was created by

Deprecated since version 4.10: This object will be removed in GTK 5

Gtk.CellAreaContext.props.minimum_height¶

Name:: minimum-height
Type:: int
Default Value:: -1
Flags:: READABLE

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

Deprecated since version 4.10: This object will be removed in GTK 5

Gtk.CellAreaContext.props.minimum_width¶

Name:: minimum-width
Type:: int
Default Value:: -1
Flags:: READABLE

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

Deprecated since version 4.10: This object will be removed in GTK 5

Gtk.CellAreaContext.props.natural_height¶

Name:: natural-height
Type:: int
Default Value:: -1
Flags:: READABLE

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

Deprecated since version 4.10: This object will be removed in GTK 5

Gtk.CellAreaContext.props.natural_width¶

Name:: natural-width
Type:: int
Default Value:: -1
Flags:: READABLE

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

Deprecated since version 4.10: This object will be removed in GTK 5