Graphics.UI.Gtk.Abstract.Container

Gtk2Hs

Graphics.UI.Gtk.Abstract.Container

Portability	portable (depends on GHC)
Stability	provisional
Maintainer	gtk2hs-users@lists.sourceforge.net

Contents

Size Requisition
Size Allocation
Child properties

Class Hierarchy

Description

Base class for widgets which contain other widgets

Synopsis

class WidgetClass o => ContainerClass o

castToContainer :: GObjectClass obj => obj -> Container

containerAdd :: (ContainerClass self, WidgetClass widget) => self -> widget -> IO ()

containerRemove :: (ContainerClass self, WidgetClass widget) => self -> widget -> IO ()

containerForeach :: ContainerClass self => self -> ContainerForeachCB -> IO ()

containerForall :: ContainerClass self => self -> ContainerForeachCB -> IO ()

containerGetChildren :: ContainerClass self => self -> IO [Widget]

data DirectionType

= DirTabForward

| DirTabBackward

containerSetFocusChild :: (ContainerClass self, WidgetClass child) => self -> child -> IO ()

containerSetFocusChain :: ContainerClass self => self -> [Widget] -> IO ()

containerGetFocusChain :: ContainerClass self => self -> IO (Maybe [Widget])

containerUnsetFocusChain :: ContainerClass self => self -> IO ()

containerSetFocusVAdjustment :: ContainerClass self => self -> Adjustment -> IO ()

containerGetFocusVAdjustment :: ContainerClass self => self -> IO (Maybe Adjustment)

containerSetFocusHAdjustment :: ContainerClass self => self -> Adjustment -> IO ()

containerGetFocusHAdjustment :: ContainerClass self => self -> IO (Maybe Adjustment)

containerResizeChildren :: ContainerClass self => self -> IO ()

containerSetBorderWidth :: ContainerClass self => self -> Int -> IO ()

containerGetBorderWidth :: ContainerClass self => self -> IO Int

containerGetResizeMode :: ContainerClass self => self -> IO ResizeMode

containerSetResizeMode :: ContainerClass self => self -> ResizeMode -> IO ()

containerChildSetProperty :: (ContainerClass self, WidgetClass child) => self -> child -> String -> GenericValue -> IO ()

containerChildGetProperty :: (ContainerClass self, WidgetClass child) => self -> child -> String -> IO GenericValue

containerResizeMode :: ContainerClass self => Attr self ResizeMode

containerBorderWidth :: ContainerClass self => Attr self Int

containerChild :: (ContainerClass self, WidgetClass widget) => WriteAttr self widget

containerFocusHAdjustment :: ContainerClass self => ReadWriteAttr self (Maybe Adjustment) Adjustment

containerFocusVAdjustment :: ContainerClass self => ReadWriteAttr self (Maybe Adjustment) Adjustment

onAdd :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

afterAdd :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

onCheckResize :: ContainerClass self => self -> IO () -> IO (ConnectId self)

afterCheckResize :: ContainerClass self => self -> IO () -> IO (ConnectId self)

onFocus :: ContainerClass con => con -> (DirectionType -> IO DirectionType) -> IO (ConnectId con)

afterFocus :: ContainerClass con => con -> (DirectionType -> IO DirectionType) -> IO (ConnectId con)

onRemove :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

afterRemove :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

onSetFocusChild :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

afterSetFocusChild :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

A Gtk+ user interface is constructed by nesting widgets inside widgets. Container widgets are the inner nodes in the resulting tree of widgets: they contain other widgets. So, for example, you might have a Window containing a Frame containing a Label. If you wanted an image instead of a textual label inside the frame, you might replace the Label widget with a Image widget.

There are two major kinds of container widgets in Gtk+. Both are subclasses of the abstract Container base class.

The first type of container widget has a single child widget and derives from Bin. These containers are decorators, which add some kind of functionality to the child. For example, a Button makes its child into a clickable button; a Frame draws a frame around its child and a Window places its child widget inside a top-level window.

The second type of container can have more than one child; its purpose is to manage layout. This means that these containers assign sizes and positions to their children. For example, a HBox arranges its children in a horizontal row, and a Table arranges the widgets it contains in a two-dimensional grid.

To fulfill its task, a layout container must negotiate the size requirements with its parent and its children. This negotiation is carried out in two phases, size requisition and size allocation.

Size Requisition

The size requisition of a widget is it's desired width and height. This is represented by a Requisition.

How a widget determines its desired size depends on the widget. A Label, for example, requests enough space to display all its text. Container widgets generally base their size request on the requisitions of their children.

The size requisition phase of the widget layout process operates top-down. It starts at a top-level widget, typically a Window. The top-level widget asks its child for its size requisition by calling widgetSizeRequest. To determine its requisition, the child asks its own children for their requisitions and so on. Finally, the top-level widget will get a requisition back from its child.

Size Allocation

When the top-level widget has determined how much space its child would like to have, the second phase of the size negotiation, size allocation, begins. Depending on its configuration (see windowSetResizable), the top-level widget may be able to expand in order to satisfy the size request or it may have to ignore the size request and keep its fixed size. It then tells its child widget how much space it gets by calling widgetSizeAllocate. The child widget divides the space among its children and tells each child how much space it got, and so on. Under normal circumstances, a Window will always give its child the amount of space the child requested.

A child's size allocation is represented by an Allocation. This contains not only a width and height, but also a position (i.e. X and Y coordinates), so that containers can tell their children not only how much space they have gotten, but also where they are positioned inside the space available to the container.

Widgets are required to honor the size allocation they receive; a size request is only a request, and widgets must be able to cope with any size.

Child properties

Container introduces child properties - these are object properties that are not specific to either the container or the contained widget, but rather to their relation. Typical examples of child properties are the position or pack-type of a widget which is contained in a Box.

To set the value of a child property, use containerChildSetProperty. To obtain the value of a child property, use containerChildGetProperty.

Class Hierarchy

 |  GObject
 |   +----Object
 |         +----Widget
 |               +----Container
 |                     +----Bin
 |                     +----Box
 |                     +----CList
 |                     +----Fixed
 |                     +----Paned
 |                     +----IconView
 |                     +----Layout
 |                     +----List
 |                     +----MenuShell
 |                     +----Notebook
 |                     +----Socket
 |                     +----Table
 |                     +----TextView
 |                     +----Toolbar
 |                     +----TreeView

data Container

show/hide

Instances

ContainerClass Container

GObjectClass Container

ObjectClass Container

WidgetClass Container

class WidgetClass o => ContainerClass o

show/hide

Instances

ContainerClass AboutDialog

ContainerClass Alignment

ContainerClass AspectFrame

ContainerClass Bin

ContainerClass Box

ContainerClass Button

ContainerClass ButtonBox

ContainerClass CList

ContainerClass CTree

ContainerClass CheckButton

ContainerClass CheckMenuItem

ContainerClass ColorButton

ContainerClass ColorSelection

ContainerClass ColorSelectionDialog

ContainerClass Combo

ContainerClass ComboBox

ContainerClass ComboBoxEntry

ContainerClass Container

ContainerClass Dialog

ContainerClass EventBox

ContainerClass Expander

ContainerClass FileChooserButton

ContainerClass FileChooserDialog

ContainerClass FileChooserWidget

ContainerClass FileSelection

ContainerClass Fixed

ContainerClass FontButton

ContainerClass FontSelection

ContainerClass FontSelectionDialog

ContainerClass Frame

ContainerClass GammaCurve

ContainerClass HBox

ContainerClass HButtonBox

ContainerClass HPaned

ContainerClass HandleBox

ContainerClass IconView

ContainerClass ImageMenuItem

ContainerClass InputDialog

ContainerClass Item

ContainerClass Layout

ContainerClass List

ContainerClass ListItem

ContainerClass Menu

ContainerClass MenuBar

ContainerClass MenuItem

ContainerClass MenuShell

ContainerClass MenuToolButton

ContainerClass MessageDialog

ContainerClass MozEmbed

ContainerClass Notebook

ContainerClass OptionMenu

ContainerClass Paned

ContainerClass Plug

ContainerClass RadioButton

ContainerClass RadioMenuItem

ContainerClass RadioToolButton

ContainerClass ScrolledWindow

ContainerClass SeparatorMenuItem

ContainerClass SeparatorToolItem

ContainerClass Socket

ContainerClass SourceView

ContainerClass Statusbar

ContainerClass Table

ContainerClass TearoffMenuItem

ContainerClass TextView

ContainerClass ToggleButton

ContainerClass ToggleToolButton

ContainerClass ToolButton

ContainerClass ToolItem

ContainerClass Toolbar

ContainerClass TreeView

ContainerClass VBox

ContainerClass VButtonBox

ContainerClass VPaned

ContainerClass Viewport

ContainerClass Window

castToContainer :: GObjectClass obj => obj -> Container

containerAdd

:: (ContainerClass self, WidgetClass widget)
=> self
-> widget	`widget` - a widget to be placed inside `container`
-> IO ()
Adds `widget` to the container. Typically used for simple containers such as `Window`, `Frame`, or `Button`; for more complicated layout containers such as `Box` or `Table`, this function will pick default packing parameters that may not be correct. So consider functions such as boxPackStart and tableAttach as an alternative to `containerAdd` in those cases. A widget may be added to only one container at a time; you can't place the same widget inside two different containers.

containerRemove

:: (ContainerClass self, WidgetClass widget)
=> self
-> widget	`widget` - a current child of `container`
-> IO ()
Removes `widget` from `container`. `widget` must be inside `container`.

containerForeach :: ContainerClass self => self -> ContainerForeachCB -> IO ()

Maps callback over each non-internal child of container. See containerForall for details on what constitutes an "internal" child. Most applications should use containerForeach, rather than containerForall.

containerForall

:: ContainerClass self
=> self
-> ContainerForeachCB	`callback` - a callback
-> IO ()
Maps `callback` over each child of `container`, including children that are considered "internal" (implementation details of the container). "Internal" children generally weren't added by the user of the container, but were added by the container implementation itself. Most applications should use `containerForeach`, rather than `containerForall`.

containerGetChildren :: ContainerClass self => self -> IO [Widget]

Returns the container's non-internal children. See containerForall for details on what constitutes an "internal" child.

data DirectionType

Editing direction

Constructors

DirTabForward
DirTabBackward
DirUp
DirDown
DirLeft
DirRight

show/hide

Instances

Enum DirectionType

containerSetFocusChild

:: (ContainerClass self, WidgetClass child)
=> self
-> child	child
-> IO ()
Give the focus to a specific child of the container.

containerSetFocusChain

:: ContainerClass self
=> self
-> [Widget]	`focusableWidgets` - the new focus chain.
-> IO ()
Sets a focus chain, overriding the one computed automatically by Gtk+. In principle each widget in the chain should be a descendant of the container, but this is not enforced by this method, since it's allowed to set the focus chain before you pack the widgets, or have a widget in the chain that isn't always packed. The necessary checks are done when the focus chain is actually traversed.

containerGetFocusChain :: ContainerClass self => self -> IO (Maybe [Widget])

Retrieves the focus chain of the container, if one has been set explicitly. If no focus chain has been explicitly set, Gtk+ computes the focus chain based on the positions of the children. In that case the function returns Nothing.

containerUnsetFocusChain :: ContainerClass self => self -> IO ()

Removes a focus chain explicitly set with containerSetFocusChain.

containerSetFocusVAdjustment

:: ContainerClass self
=> self
-> Adjustment	`adjustment` - an adjustment which should be adjusted when the focus is moved among the descendents of `container`
-> IO ()
Hooks up an adjustment to focus handling in a container, so when a child of the container is focused, the adjustment is scrolled to show that widget. This function sets the vertical alignment. See scrolledWindowGetVAdjustment for a typical way of obtaining the adjustment and `containerSetFocusHAdjustment` for setting the horizontal adjustment. The adjustments have to be in pixel units and in the same coordinate system as the allocation for immediate children of the container.

containerGetFocusVAdjustment

:: ContainerClass self
=> self
-> IO (Maybe Adjustment)	returns the vertical focus adjustment, or `Nothing` if none has been set.
Retrieves the vertical focus adjustment for the container. See `containerSetFocusVAdjustment`.

containerSetFocusHAdjustment

:: ContainerClass self
=> self
-> Adjustment	`adjustment` - an adjustment which should be adjusted when the focus is moved among the descendents of `container`
-> IO ()
Hooks up an adjustment to focus handling in a container, so when a child of the container is focused, the adjustment is scrolled to show that widget. This function sets the horizontal alignment. See scrolledWindowGetHAdjustment for a typical way of obtaining the adjustment and `containerSetFocusVAdjustment` for setting the vertical adjustment. The adjustments have to be in pixel units and in the same coordinate system as the allocation for immediate children of the container.

containerGetFocusHAdjustment

:: ContainerClass self
=> self
-> IO (Maybe Adjustment)	returns the horizontal focus adjustment, or `Nothing` if none has been set.
Retrieves the horizontal focus adjustment for the container. See `containerSetFocusHAdjustment`.

containerResizeChildren :: ContainerClass self => self -> IO ()

Make the container resize its children.

containerSetBorderWidth

:: ContainerClass self
=> self
-> Int	`borderWidth` - amount of blank space to leave outside the container. Valid values are in the range 0-65535 pixels.
-> IO ()
Sets the border width of the container. The border width of a container is the amount of space to leave around the outside of the container. The only exception to this is `Window`; because toplevel windows can't leave space outside, they leave the space inside. The border is added on all sides of the container. To add space to only one side, one approach is to create a `Alignment` widget, call widgetSetUsize to give it a size, and place it on the side of the container as a spacer.

containerGetBorderWidth

:: ContainerClass self
=> self
-> IO Int	returns the current border width
Retrieves the border width of the container. See `containerSetBorderWidth`.

containerGetResizeMode

:: ContainerClass self
=> self
-> IO ResizeMode	returns the current resize mode
Returns the resize mode for the container. See `containerSetResizeMode`.

containerSetResizeMode

:: ContainerClass self
=> self
-> ResizeMode	`resizeMode` - the new resize mode.
-> IO ()
Sets the resize mode for the container. The resize mode of a container determines whether a resize request will be passed to the container's parent, queued for later execution or executed immediately.

containerChildSetProperty

:: (ContainerClass self, WidgetClass child)
=> self
-> child	`child` - a widget which is a child of the container
-> String	`propertyName` - the name of the property to set
-> GenericValue	`value` - the value to set the property to
-> IO ()
Sets a child property for `child` and the container.

containerChildGetProperty

:: (ContainerClass self, WidgetClass child)
=> self
-> child	`child` - a widget which is a child of the container
-> String	`propertyName` - the name of the property to get
-> IO GenericValue
Gets the value of a child property for `child` and the container.

containerResizeMode :: ContainerClass self => Attr self ResizeMode

Specify how resize events are handled.

Default value: ResizeParent

containerBorderWidth :: ContainerClass self => Attr self Int

The width of the empty border outside the containers children.

Allowed values: <= (maxBound :: Int)

Default value: 0

containerChild :: (ContainerClass self, WidgetClass widget) => WriteAttr self widget

Can be used to add a new child to the container.

containerFocusHAdjustment :: ContainerClass self => ReadWriteAttr self (Maybe Adjustment) Adjustment

'focusHadjustment' property. See containerGetFocusHAdjustment and containerSetFocusHAdjustment

containerFocusVAdjustment :: ContainerClass self => ReadWriteAttr self (Maybe Adjustment) Adjustment

'focusVadjustment' property. See containerGetFocusVAdjustment and containerSetFocusVAdjustment

onAdd :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

This signal is called each time a new widget is added to this container.

afterAdd :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

onCheckResize :: ContainerClass self => self -> IO () -> IO (ConnectId self)

This signal is called when the widget is resized.

afterCheckResize :: ContainerClass self => self -> IO () -> IO (ConnectId self)

onFocus :: ContainerClass con => con -> (DirectionType -> IO DirectionType) -> IO (ConnectId con)

This signal is called if the container receives the input focus.

afterFocus :: ContainerClass con => con -> (DirectionType -> IO DirectionType) -> IO (ConnectId con)

onRemove :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

This signal is called for each widget that is removed from the container.

afterRemove :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

onSetFocusChild :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

This signal is called if a child in the container receives the input focus.

afterSetFocusChild :: ContainerClass self => self -> (Widget -> IO ()) -> IO (ConnectId self)

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