com.badlogic.gdx.scenes.scene2d.utils

Interface Layout

All Known Implementing Classes:

Button, CheckBox, Container, Dialog, HorizontalGroup, Image, ImageButton, ImageTextButton, Label, List, ProgressBar, ScrollPane, SelectBox, Slider, SplitPane, Stack, Table, TextArea, TextButton, TextField, Touchpad, Tree, VerticalGroup, Widget, WidgetGroup, Window

public interface Layout

Provides methods for an actor to participate in layout and to provide a minimum, preferred, and maximum size.

Author:

Nathan Sweet

Method Summary

Methods

Modifier and Type	Method and Description
float	getMaxHeight() Zero indicates no max height.
float	getMaxWidth() Zero indicates no max width.
float	getMinHeight()
float	getMinWidth()
float	getPrefHeight()
float	getPrefWidth()
void	invalidate() Invalidates this actor's layout, causing layout() to happen the next time validate() is called.
void	invalidateHierarchy() Invalidates this actor and all its parents, calling invalidate() on each.
void	layout() Computes and caches any information needed for drawing and, if this actor has children, positions and sizes each child, calls invalidate() any each child whose width or height has changed, and calls validate() on each child.
void	pack() Sizes this actor to its preferred width and height, then calls validate().
void	setFillParent(boolean fillParent) If true, this actor will be sized to the parent in validate().
void	setLayoutEnabled(boolean enabled) Enables or disables the layout for this actor and all child actors, recursively.
void	validate() Ensures the actor has been laid out.

Method Detail

layout

void layout()

Computes and caches any information needed for drawing and, if this actor has children, positions and sizes each child, calls invalidate() any each child whose width or height has changed, and calls validate() on each child. This method should almost never be called directly, instead validate() should be used.

invalidate

void invalidate()

Invalidates this actor's layout, causing layout() to happen the next time validate() is called. This method should be called when state changes in the actor that requires a layout but does not change the minimum, preferred, maximum, or actual size of the actor (meaning it does not affect the parent actor's layout).

invalidateHierarchy

void invalidateHierarchy()

Invalidates this actor and all its parents, calling invalidate() on each. This method should be called when state changes in the actor that affects the minimum, preferred, maximum, or actual size of the actor (meaning it it potentially affects the parent actor's layout).

validate

void validate()

Ensures the actor has been laid out. Calls layout() if invalidate() has been called since the last time validate() was called, or if the actor otherwise needs to be laid out. This method is usually called in Actor.draw(Batch, float) before drawing is performed.

pack

void pack()

Sizes this actor to its preferred width and height, then calls validate().

Generally this method should not be called in an actor's constructor because it calls layout(), which means a subclass would have layout() called before the subclass' constructor. Instead, in constructors simply set the actor's size to getPrefWidth() and getPrefHeight(). This allows the actor to have a size at construction time for more convenient use with groups that do not layout their children.

setFillParent

void setFillParent(boolean fillParent)

If true, this actor will be sized to the parent in validate(). If the parent is the stage, the actor will be sized to the stage. This method is for convenience only when the widget's parent does not set the size of its children (such as the stage).

setLayoutEnabled

void setLayoutEnabled(boolean enabled)

Enables or disables the layout for this actor and all child actors, recursively. When false, validate() will not cause a layout to occur. This can be useful when an actor will be manipulated externally, such as with actions. Default is true.

getMinWidth

float getMinWidth()

getMinHeight

float getMinHeight()

getPrefWidth

float getPrefWidth()

getPrefHeight

float getPrefHeight()

getMaxWidth

float getMaxWidth()

Zero indicates no max width.

getMaxHeight

float getMaxHeight()

Zero indicates no max height.