javax.swing
Class OverlayLayout

java.lang.Object
  javax.swing.OverlayLayout

All Implemented Interfaces:

LayoutManager, LayoutManager2, Serializable

public class OverlayLayout

extends Object

implements LayoutManager2, Serializable

A layout manager to arrange components over the top of each other. The requested size of the container will be the largest requested size of the children, taking alignment needs into consideration. The alignment is based upon what is needed to properly fit the children in the allocation area. The children will be placed such that their alignment points are all on top of each other.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans^TM has been added to the java.beans package. Please see XMLEncoder.

Author:

Timothy Prinzing

See Also:

Serialized Form

Field Summary

private Container	target
private SizeRequirements[]	xChildren
private SizeRequirements	xTotal
private SizeRequirements[]	yChildren
private SizeRequirements	yTotal

Constructor Summary

OverlayLayout(Container target)
Constructs a layout manager that performs overlay arrangement of the children.

Method Summary

void	addLayoutComponent(Component comp, Object constraints) Adds the specified component to the layout, using the specified constraint object.
void	addLayoutComponent(String name, Component comp) Adds the specified component to the layout.
(package private) void	checkContainer(Container target)
(package private) void	checkRequests()
float	getLayoutAlignmentX(Container target) Returns the alignment along the x axis for the container.
float	getLayoutAlignmentY(Container target) Returns the alignment along the y axis for the container.
void	invalidateLayout(Container target) Indicates a child has changed its layout related information, which causes any cached calculations to be flushed.
void	layoutContainer(Container target) Called by the AWT when the specified container needs to be laid out.
Dimension	maximumLayoutSize(Container target) Returns the minimum dimensions needed to lay out the components contained in the specified target container.
Dimension	minimumLayoutSize(Container target) Returns the minimum dimensions needed to lay out the components contained in the specified target container.
Dimension	preferredLayoutSize(Container target) Returns the preferred dimensions for this layout given the components in the specified target container.
void	removeLayoutComponent(Component comp) Removes the specified component from the layout.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

target

private Container target

xChildren

private SizeRequirements[] xChildren

yChildren

private SizeRequirements[] yChildren

xTotal

private SizeRequirements xTotal

yTotal

private SizeRequirements yTotal

Constructor Detail

OverlayLayout

public OverlayLayout(Container target)

Constructs a layout manager that performs overlay arrangement of the children. The layout manager created is dedicated to the given container.

Parameters:

target - the container to do layout against

Method Detail

invalidateLayout

public void invalidateLayout(Container target)

Indicates a child has changed its layout related information, which causes any cached calculations to be flushed.

Specified by:

invalidateLayout in interface LayoutManager2

Parameters:

target - the container

addLayoutComponent

public void addLayoutComponent(String name,
                               Component comp)

Adds the specified component to the layout. Used by this class to know when to invalidate layout.

Specified by:

addLayoutComponent in interface LayoutManager

Parameters:

name - the name of the component

comp - the the component to be added

removeLayoutComponent

public void removeLayoutComponent(Component comp)

Removes the specified component from the layout. Used by this class to know when to invalidate layout.

Specified by:

removeLayoutComponent in interface LayoutManager

Parameters:

comp - the component to remove

addLayoutComponent

public void addLayoutComponent(Component comp,
                               Object constraints)

Adds the specified component to the layout, using the specified constraint object. Used by this class to know when to invalidate layout.

Specified by:

addLayoutComponent in interface LayoutManager2

Parameters:

comp - the component to be added

constraints - where/how the component is added to the layout.

preferredLayoutSize

public Dimension preferredLayoutSize(Container target)

Returns the preferred dimensions for this layout given the components in the specified target container. Recomputes the layout if it has been invalidated. Factors in the current inset setting returned by getInsets().

Specified by:

preferredLayoutSize in interface LayoutManager

Parameters:

target - the component which needs to be laid out

Returns:

a Dimension object containing the preferred dimensions

See Also:

minimumLayoutSize(java.awt.Container)

minimumLayoutSize

public Dimension minimumLayoutSize(Container target)

Returns the minimum dimensions needed to lay out the components contained in the specified target container. Recomputes the layout if it has been invalidated, and factors in the current inset setting.

Specified by:

minimumLayoutSize in interface LayoutManager

Parameters:

target - the component which needs to be laid out

Returns:

a Dimension object containing the minimum dimensions

See Also:

preferredLayoutSize(java.awt.Container)

maximumLayoutSize

public Dimension maximumLayoutSize(Container target)

Returns the minimum dimensions needed to lay out the components contained in the specified target container. Recomputes the layout if it has been invalidated, and factors in the inset setting returned by getInset().

Specified by:

maximumLayoutSize in interface LayoutManager2

Parameters:

target - the component which needs to be laid out

Returns:

a Dimension object containing the maximum dimensions

See Also:

preferredLayoutSize(java.awt.Container)

getLayoutAlignmentX

public float getLayoutAlignmentX(Container target)

Returns the alignment along the x axis for the container.

Specified by:

getLayoutAlignmentX in interface LayoutManager2

Parameters:

target - the container

Returns:

the alignment >= 0.0f && <= 1.0f

getLayoutAlignmentY

public float getLayoutAlignmentY(Container target)

Returns the alignment along the y axis for the container.

Specified by:

getLayoutAlignmentY in interface LayoutManager2

Parameters:

target - the container

Returns:

the alignment >= 0.0f && <= 1.0f

layoutContainer

public void layoutContainer(Container target)

Called by the AWT when the specified container needs to be laid out.

Specified by:

layoutContainer in interface LayoutManager

Parameters:

target - the container to lay out

Throws:

AWTError - if the target isn't the container specified to the constructor

checkContainer

void checkContainer(Container target)

checkRequests

void checkRequests()