com.wordpress.tipsforjava.swing
[Java] Class RelativeLayout

java.lang.Object
  com.wordpress.tipsforjava.swing.RelativeLayout

All Implemented Interfaces:

LayoutManager2, Serializable

public class RelativeLayout
extends Object

The RelativeLayout class is a layout manager that lays out a container's components on the specified X or Y axis. Components can be layed out at their preferred size or at a relative size. When relative sizing is used the component must be added to the container using a relative size constraint, which is simply a Float value. The space available for relative sized components is determined by subtracting the preferred size of the other components from the space available in the container. Each component is then assigned a size based on its relative size value. For example: container.add(component1, new Float(1)); container.add(component2, new Float(2)); There is a total of 3 relative units. If the container has 300 pixels of space available then component1 will get 100 and component2, 200. It is possible that rounding errors will occur in which case you can specify a rounding policy to use to allocate the extra pixels. By defaults components are center aligned on the secondary axis however this can be changed at the container or component level.

Authors:

Rob Camick

Darryl Burke

CENTER

public static final float CENTER

COMPONENT

public static final float COMPONENT

DO_NOTHING

public static final int DO_NOTHING

EQUAL

public static final int EQUAL

FIRST

public static final int FIRST

LARGEST

public static final int LARGEST

LAST

public static final int LAST

LEADING

public static final float LEADING

MINIMUM

private static final int MINIMUM

PREFERRED

private static final int PREFERRED

TRAILING

public static final float TRAILING

X_AXIS

public static final int X_AXIS

Y_AXIS

public static final int Y_AXIS

alignment

private float alignment

The alignment of the Components on the other axis of the Container. For X-AXIS this would refer to the Y alignemt. For Y-AXIS this would refer to the X alignment.

axis

private int axis

The axis of the Components within the Container.

borderGap

private int borderGap

The gap (in pixels) used before the leading component and after the trailing component. It can be changed at any time and should be a non-negative integer.

constraints

private HashMap constraints

fill

private boolean fill

fillGap

private int fillGap

gap

private int gap

This is the gap (in pixels) which specifies the space between components It can be changed at any time and should be a non-negative integer.

roundingPolicy

private int roundingPolicy

RelativeLayout

public RelativeLayout()

Creates a relative layout with the components layed out on the X-Axis using the default gap

RelativeLayout

public RelativeLayout(int axis)

Creates a relative layout with the components layed out on the specified axis using the default gap

Parameters:

axis - X-AXIS or Y_AXIS

RelativeLayout

public RelativeLayout(int axis, int gap)

Creates a relative layout with the components layed out on the specified axis using the specfied gap

All RelativeLayout constructors defer to this one.

Parameters:

axis - X-AXIS or Y_AXIS

gap - the gap

addLayoutComponent

public void addLayoutComponent(String name, Component component)

Not supported

addLayoutComponent

public void addLayoutComponent(Component component, Object constraint)

adjustEqual

private void adjustEqual(int[] relativeSpace, int spaceRemaining)

adjustFirst

private void adjustFirst(int[] relativeSpace, int spaceRemaining)

adjustForRounding

protected void adjustForRounding(int[] relativeSpace, int spaceRemaining)

adjustLargest

private void adjustLargest(int[] relativeSpace, int spaceRemaining)

adjustLast

private void adjustLast(int[] relativeSpace, int spaceRemaining)

allocateRelativeSpace

private int[] allocateRelativeSpace(Container parent, int spaceAvailable, float relativeTotal)

getAlignment

public float getAlignment()

Gets the alignment of the components on the opposite axis.

Returns:

the alignment

getAxis

public int getAxis()

Gets the layout axis.

Returns:

the layout axis

getBorderGap

public int getBorderGap()

Gets the initial gap. This gap is used before the leading component and after the trailing component.

Returns:

the leading/trailing gap

getConstraints

public Float getConstraints(Component component)

Gets the constraints for the specified component.

Parameters:

component - the component to be queried

Returns:

the constraint for the specified component, or null if component is null or is not present in this layout

getDimension

private Dimension getDimension(Component component, int type)

getFillGap

public int getFillGap()

Gets the fill gap amount.

Returns:

the fill gap value

getGap

public int getGap()

Gets the gap between components.

Returns:

the gap between components

getLayoutAlignmentX

public float getLayoutAlignmentX(Container parent)

Returns the alignment along the x axis. Use center alignment.

getLayoutAlignmentY

public float getLayoutAlignmentY(Container parent)

Returns the alignment along the y axis. Use center alignment.

getLayoutSize

private Dimension getLayoutSize(Container parent, int type)

getLocationX

private int getLocationX(Component component, int width)

getLocationY

private int getLocationY(Component component, int height)

getRoundingPolicy

public int getRoundingPolicy()

Gets the rounding policy.

Returns:

the rounding policy

getVisibleComponents

private int getVisibleComponents(Container container)

invalidateLayout

public void invalidateLayout(Container target)

Invalidates the layout, indicating that if the layout manager has cached information it should be discarded.

isFill

public boolean isFill()

Gets the fill property for the component size on the opposite edge.

Returns:

the fill property

layoutContainer

public void layoutContainer(Container parent)

Lays out the specified container using this layout.

This method reshapes the components in the specified target container in order to satisfy the constraints of the RelativeLayout object.

The grid layout manager determines the size of individual components by dividing the free space in the container into equal-sized portions according to the number of rows and columns in the layout. The container's free space equals the container's size minus any insets and any specified horizontal or vertical gap. All components in a grid layout are given the same size.

Parameters:

target - the container in which to do the layout

See Also:

Container

Container.doLayout

layoutContainerHorizontally

private void layoutContainerHorizontally(Container parent)

layoutContainerVertically

private void layoutContainerVertically(Container parent)

maximumLayoutSize

public Dimension maximumLayoutSize(Container target)

There is no maximum.

minimumLayoutSize

public Dimension minimumLayoutSize(Container parent)

Determines the minimum size of the container argument using this column layout.

The minimum width of a grid layout is the largest minimum width of each column in the container, plus the horizontal padding times the number of columns minus one, plus the left and right insets of the target container.

The minimum height of a column layout is the largest minimum height of each row in the container, plus the vertical padding times the number of rows minus one, plus the top and bottom insets of the target container.

Parameters:

target - the container in which to do the layout

Returns:

the minimum dimensions needed to lay out the subcomponents of the specified container

See Also:

RelativeLayout.preferredLayoutSize

Container.doLayout

preferredLayoutSize

public Dimension preferredLayoutSize(Container parent)

Determines the preferred size of the container argument using this column layout.

The preferred width of a column layout is the largest preferred width of each column in the container, plus the horizontal padding times the number of columns minus one, plus the left and right insets of the target container.

The preferred height of a column layout is the largest preferred height of each row in the container, plus the vertical padding times the number of rows minus one, plus the top and bottom insets of the target container.

Parameters:

target - the container in which to do the layout

Returns:

the preferred dimensions to lay out the subcomponents of the specified container

See Also:

RelativeLayout.minimumLayoutSize

Container.getPreferredSize

removeLayoutComponent

public void removeLayoutComponent(Component comp)

Removes the specified component from the layout.

Parameters:

comp - the component to be removed

setAlignment

public void setAlignment(float alignment)

setAxis

public void setAxis(int axis)

Sets the layout axis

Parameters:

axis - the layout axis

setBorderGap

public void setBorderGap(int borderGap)

Sets the initial gap. This gap is used before the leading component and after the trailing component. The default is set to the gap.

Parameters:

borderGap - the leading/trailing gap

setFill

public void setFill(boolean fill)

Change size of relative components to fill the space available For X-AXIS aligned components the height will be filled. For Y-AXIS aligned components the width will be filled.

setFillGap

public void setFillGap(int fillGap)

Specify the number of pixels by which the fill size is decreased when setFill(true) has been specified.

setGap

public void setGap(int gap)

Sets the gap between components to the specified value.

Parameters:

gap - the gap between components

setRoundingPolicy

public void setRoundingPolicy(int roundingPolicy)

Specify the rounding policy to be used when all the avialable pixels have not been allocated to a component. DO_NOTHING FIRST - extra pixels added to the first relative component LAST - extra pixels added to the last relative component LARGEST (default) - extra pixels added to the larger relative component EQUAL - a single pixel is added to each relative component (until pixels are used up)

toString

public String toString()

Returns the string representation of this column layout's values.

Returns:

a string representation of this grid layout

Groovy Documentation