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Gtk.CellAreaContext

class — extends GObject.Object

:::warning Deprecated since 4.10 This API is deprecated. :::

Stores geometrical information for a series of rows in a GtkCellArea

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 CellArea.event.

Methods

allocate

def allocate(self, width: int, height: int) -> None

:::warning Deprecated since 4.10 This API is deprecated. :::

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.

Parameters:

  • width — the allocated width for all GtkTreeModel rows rendered with context, or -1
  • height — the allocated height for all GtkTreeModel rows rendered with context, or -1

get_allocation

def get_allocation(self) -> tuple[int, int]

:::warning Deprecated since 4.10 This API is deprecated. :::

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 CellAreaContext.reset, the returned value will be -1.

get_area

def get_area(self) -> CellArea

:::warning Deprecated since 4.10 This API is deprecated. :::

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.

get_preferred_height

def get_preferred_height(self) -> tuple[int, int]

:::warning Deprecated since 4.10 This API is deprecated. :::

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

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

get_preferred_height_for_width

def get_preferred_height_for_width(self, width: int) -> tuple[int, int]

:::warning Deprecated since 4.10 This API is deprecated. :::

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

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

Parameters:

  • width — a proposed width for allocation

get_preferred_width

def get_preferred_width(self) -> tuple[int, int]

:::warning Deprecated since 4.10 This API is deprecated. :::

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

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

get_preferred_width_for_height

def get_preferred_width_for_height(self, height: int) -> tuple[int, int]

:::warning Deprecated since 4.10 This API is deprecated. :::

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

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

Parameters:

  • height — a proposed height for allocation

push_preferred_height

def push_preferred_height(self, minimum_height: int, natural_height: int) -> None

:::warning Deprecated since 4.10 This API is deprecated. :::

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 CellArea.get_preferred_height requests.

Parameters:

  • minimum_height — the proposed new minimum height for context
  • natural_height — the proposed new natural height for context

push_preferred_width

def push_preferred_width(self, minimum_width: int, natural_width: int) -> None

:::warning Deprecated since 4.10 This API is deprecated. :::

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 CellArea.get_preferred_width requests.

Parameters:

  • minimum_width — the proposed new minimum width for context
  • natural_width — the proposed new natural width for context

reset

def reset(self) -> None

:::warning Deprecated since 4.10 This API is deprecated. :::

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 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 CellArea.get_preferred_height_for_width.

Virtual methods

do_allocate

def do_allocate(self, width: int, height: int) -> None

:::warning Deprecated since 4.10 This API is deprecated. :::

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.

Parameters:

  • width — the allocated width for all GtkTreeModel rows rendered with context, or -1
  • height — the allocated height for all GtkTreeModel rows rendered with context, or -1

do_get_preferred_height_for_width

def do_get_preferred_height_for_width(self, width: int) -> tuple[int, int]

:::warning Deprecated since 4.10 This API is deprecated. :::

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

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

Parameters:

  • width — a proposed width for allocation

do_get_preferred_width_for_height

def do_get_preferred_width_for_height(self, height: int) -> tuple[int, int]

:::warning Deprecated since 4.10 This API is deprecated. :::

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

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

Parameters:

  • height — a proposed height for allocation

do_reset

def do_reset(self) -> None

:::warning Deprecated since 4.10 This API is deprecated. :::

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 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 CellArea.get_preferred_height_for_width.

Properties

area

area: CellArea  # read/write

:::warning Deprecated since 4.10 This API is deprecated. :::

The GtkCellArea this context was created by

minimum_height

minimum_height: int  # read-only

:::warning Deprecated since 4.10 This API is deprecated. :::

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

minimum_width

minimum_width: int  # read-only

:::warning Deprecated since 4.10 This API is deprecated. :::

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

natural_height

natural_height: int  # read-only

:::warning Deprecated since 4.10 This API is deprecated. :::

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

natural_width

natural_width: int  # read-only

:::warning Deprecated since 4.10 This API is deprecated. :::

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