Graphics.UI.Gtk.Abstract.Box

Gtk2Hs

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

Contents

Detail
Class Hierarchy
Types
Methods
Attributes
Child Attributes

Description

Base class for box containers

Synopsis

data Box

class ContainerClass o => BoxClass o

castToBox :: GObjectClass obj => obj -> Box

data Packing

= PackRepel

| PackGrow

| PackNatural

boxPackStart :: (BoxClass self, WidgetClass child) => self -> child -> Packing -> Int -> IO ()

boxPackEnd :: (BoxClass self, WidgetClass child) => self -> child -> Packing -> Int -> IO ()

boxPackStartDefaults :: (BoxClass self, WidgetClass widget) => self -> widget -> IO ()

boxPackEndDefaults :: (BoxClass self, WidgetClass widget) => self -> widget -> IO ()

boxGetHomogeneous :: BoxClass self => self -> IO Bool

boxSetHomogeneous :: BoxClass self => self -> Bool -> IO ()

boxGetSpacing :: BoxClass self => self -> IO Int

boxSetSpacing :: BoxClass self => self -> Int -> IO ()

boxReorderChild :: (BoxClass self, WidgetClass child) => self -> child -> Int -> IO ()

boxQueryChildPacking :: (BoxClass self, WidgetClass child) => self -> child -> IO (Packing, Int, PackType)

boxSetChildPacking :: (BoxClass self, WidgetClass child) => self -> child -> Packing -> Int -> PackType -> IO ()

boxSpacing :: BoxClass self => Attr self Int

boxHomogeneous :: BoxClass self => Attr self Bool

boxChildPacking :: (BoxClass self, WidgetClass child) => child -> Attr self Packing

boxChildPadding :: (BoxClass self, WidgetClass child) => child -> Attr self Int

boxChildPackType :: (BoxClass self, WidgetClass child) => child -> Attr self PackType

boxChildPosition :: (BoxClass self, WidgetClass child) => child -> Attr self Int

Detail

Box is an abstract widget which encapsulates functionality for a particular kind of container, one that organizes a variable number of widgets into a rectangular area. Box currently has two derived classes, HBox and VBox.

The rectangular area of a Box is organized into either a single row or a single column of child widgets depending upon whether the box is of type HBox or VBox, respectively. Thus, all children of a Box are allocated one dimension in common, which is the height of a row, or the width of a column. Box uses a notion of packing. Packing refers to adding widgets with reference to a particular position in a Container. For a Box, there are two reference positions: the start and the end of the box. For a VBox, the start is defined as the top of the box and the end is defined as the bottom. For a HBox the start is defined as the left side and the end is defined as the right side.

Use repeated calls to boxPackStart to pack widgets into a Box from start to end. Use boxPackEnd to add widgets from end to start. You may intersperse these calls and add widgets from both ends of the same Box. Besides adding widgets at the start or the end of a box, you can also specify the padding around each widget (in pixels) and a Packing parameter that denotes how to fill up unused space. The functions boxPackStartDefaults or boxPackEndDefaults are a convenient way to pack widgets into a Box without specifying these extra paramters.

While the right amount of padding around each widget is a matter of appearance, the Packing paramter specifies the way the widgets in the container behave when the window is resized and thereby affect the usability. Hence, once you have created a window, you should resize it and see if the widgets behave as expected. The Packing parameter of each child widget determines how excess space is used by that particular widget. See the description of Packing for a detailed explanaition.

Because Box is a Container, you may also use containerAdd to insert widgets into the box, and they will be packed as if with boxPackStartDefaults. Use containerRemove to remove widgets from the Box.

Use boxSetHomogeneous to specify whether or not all children of the Box are forced to get the same amount of space. Note that the Packing options PackNatural and PackRepel coincide if space is allotted homogeneously.

Use boxSetSpacing to determine how much space will be minimally placed between all children in the Box.

Use boxReorderChild to move a Box child to a different place in the box.

Use boxSetChildPacking to reset the expand, fill, and padding attributes of any Box child. Use boxQueryChildPacking to query these fields.

Class Hierarchy

 |  GObject
 |   +----Object
 |         +----Widget
 |               +----Container
 |                     +----Box
 |                           +----ButtonBox
 |                           +----VBox
 |                           +----HBox

Types

data Box

Instances

class ContainerClass o => BoxClass o

castToBox :: GObjectClass obj => obj -> Box

data Packing

Packing parameters of a widget

The Packing parameter determines how the child behaves in the horizontal or vertical way in an HBox or VBox, respectively. PackNatural means the child is as big as it reqests. It will stay at the start of the end of a Box if there is more space availble. All children packed with PackRepel will be padded on both sides with additional space. PackGrow will increase the size of a widget so that it covers the available space. A menu bar, for instance, should always stay at the top of a window and should only occupy as little space as possible. Hence it should be packed at the start of a VBox with the packing option PackNatural. The working area of a window (e.g. the text area in an editor) should expand when the window is resized. Here the packing option PackGrow is the right choice and it is irrelevant whether the main area is inserted at the start or the end of a box. Finally PackRepel is most useful in a window where no widget can make use of excess space. Examples include a dialog box without list boxes or text fields.

Constructors

PackRepel
PackGrow
PackNatural

Instances

Enum Packing

Eq Packing

Methods

boxPackStart

:: (BoxClass self, WidgetClass child)
=> self
-> child	`child` - the `Widget` to be added to the box.
-> Packing
-> Int	`padding` - extra space in pixels to put between this child and its neighbors, over and above the global amount specified by spacing `boxSetSpacing`. If `child` is a widget at one of the reference ends of `box`, then `padding` pixels are also put between `child` and the reference edge of `box`.
-> IO ()
Adds the `child` widget to the box, packed with reference to the start of the box. The `child` is packed after any other child packed with reference to the start of the box.

boxPackEnd

:: (BoxClass self, WidgetClass child)
=> self
-> child	`child` - the `Widget` to be added to the box.
-> Packing
-> Int	`padding` - extra space in pixels to put between this child and its neighbors, over and above the global amount specified by spacing `boxSetSpacing`. If `child` is a widget at one of the reference ends of `box`, then `padding` pixels are also put between `child` and the reference edge of `box`.
-> IO ()
Adds the `child` widget to the box, packed with reference to the end of the box. The `child` is packed after (away from end of) any other child packed with reference to the end of the box. Note that for `boxPackEnd` the `PackNatural` option will move a child to the right in an `HBox` or to the bottom in an `VBox` if there is more space availble.

boxPackStartDefaults

:: (BoxClass self, WidgetClass widget)
=> self
-> widget	`widget` - the `Widget` to be added to the box.
-> IO ()
Like `boxPackStart` but uses the default parameters `PackRepel` and 0 for padding.

boxPackEndDefaults

:: (BoxClass self, WidgetClass widget)
=> self
-> widget	`widget` - the `Widget` to be added to the box.
-> IO ()
Like `boxPackEnd` but uses the default parameters `PackRepel` and 0 for padding.

boxGetHomogeneous

:: BoxClass self
=> self
-> IO Bool	returns `True` if the box is homogeneous.
Returns whether the box is homogeneous (all children are the same size). See `boxSetHomogeneous`.

boxSetHomogeneous

:: BoxClass self
=> self
-> Bool	`homogeneous` - a boolean value, `True` to create equal allotments, `False` for variable allotments.
-> IO ()
Sets the homogeneous property, controlling whether or not all children of the box are given equal space

boxGetSpacing

:: BoxClass self
=> self
-> IO Int	returns spacing between children
Retrieves the standard spacing between widgets.

boxSetSpacing

:: BoxClass self
=> self
-> Int	`spacing` - the number of pixels to put between children.
-> IO ()
Set the standard spacing between two children. This space is in addition to the padding parameter that is given for each child.

boxReorderChild

:: (BoxClass self, WidgetClass child)
=> self
-> child	`child` - the `Widget` to move.
-> Int	`position` - the new position for `child` in the children list starting from 0. If negative, indicates the end of the list.
-> IO ()
Moves `child` to a new `position` in the list of `box` children. The list contains both widgets packed `PackStart` as well as widgets packed `PackEnd`, in the order that these widgets were added to the box. A widget's position in the box children list determines where the widget is packed into the box. A child widget at some position in the list will be packed just after all other widgets of the same packing type that appear earlier in the list.

boxQueryChildPacking

:: (BoxClass self, WidgetClass child)
=> self
-> child	`child` - the `Widget` of the child to query.
-> IO (Packing, Int, PackType)	(packing, padding, packType)
Returns information about how `child` is packed into the box. Returns information on the behaviour if free space is available (in `Packing`), the additional padding for this widget and if the widget was inserted at the start or end of the container (`PackType`).

boxSetChildPacking

:: (BoxClass self, WidgetClass child)
=> self
-> child	`child` - the `Widget` of the child to set.
-> Packing
-> Int	padding
-> PackType	packType
-> IO ()
Sets the way `child` is packed into the box.

Attributes

boxSpacing :: BoxClass self => Attr self Int

The amount of space between children.

Allowed values: >= 0

Default value: 0

boxHomogeneous :: BoxClass self => Attr self Bool

Whether the children should all be the same size.

Default value: False

Child Attributes

boxChildPacking :: (BoxClass self, WidgetClass child) => child -> Attr self Packing

The packing style of the child.

Default value: PackGrow

boxChildPadding :: (BoxClass self, WidgetClass child) => child -> Attr self Int

Extra space to put between the child and its neighbors, in pixels.

Allowed values: <= (maxBound :: Int)

Default value: 0

boxChildPackType :: (BoxClass self, WidgetClass child) => child -> Attr self PackType

A PackType indicating whether the child is packed with reference to the start or end of the parent.

Default value: PackStart

boxChildPosition :: (BoxClass self, WidgetClass child) => child -> Attr self Int

The index of the child in the parent.

Allowed values: >= -1

Default value: 0

Produced by Haddock version 0.7