com.codename1.ui.layouts

Class LayoutStyle

java.lang.Object

com.codename1.ui.layouts.LayoutStyle

public class LayoutStyle
extends Object

LayoutStyle is used to determine how much space to place between components during layout. LayoutStyle can be obtained for two components, or for a component relative to an edge of a parent container. The amount of space can vary depending upon whether or not the components are logically grouped together (RELATED).

This class is primarily useful for JREs prior to 1.6. In 1.6 API for this was added to Swing. When run on a JRE of 1.6 or greater this will call into the appropriate methods in Swing.

Field Summary

Fields

Modifier and Type	Field and Description
static int	INDENT Possible argument to getPreferredGap.
static int	RELATED Possible argument to getPreferredGap.
static int	UNRELATED Possible argument to getPreferredGap.

Constructor Summary

Constructors

Constructor and Description
LayoutStyle()

Method Summary

Modifier and Type	Method and Description
int	getContainerGap(Component component, int position, Container parent) Returns the amount of space to position a component inside its parent.
int	getPreferredGap(Component component1, Component component2, int type, int position, Container parent) Returns the amount of space to use between two components.
static LayoutStyle	getSharedInstance() Factory methods for obtaining the current LayoutStyle object appropriate for the current look and feel.
static void	setSharedInstance(LayoutStyle layout) Sets the LayoutStyle instance to use for this look and feel.

Methods inherited from class java.lang.Object

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

Field Detail

RELATED

public static final int RELATED

Possible argument to getPreferredGap. Used to indicate the two components are grouped together.

See Also:

Constant Field Values

UNRELATED

public static final int UNRELATED

Possible argument to getPreferredGap. Used to indicate the two components are not grouped together.

See Also:

Constant Field Values

INDENT

public static final int INDENT

Possible argument to getPreferredGap. Used to indicate the distance to indent a component is being requested. To visually indicate a set of related components they will often times be horizontally indented, the INDENT constant for this. For example, to indent a check box relative to a label use this constant to getPreferredGap.

See Also:

Constant Field Values

Constructor Detail

LayoutStyle

public LayoutStyle()

Method Detail

setSharedInstance

public static void setSharedInstance(LayoutStyle layout)

Sets the LayoutStyle instance to use for this look and feel. You generally don't need to invoke this, instead use the getter which will return the LayoutStyle appropriate for the current look and feel.

Parameters:

layout - the LayoutStyle to use; a value of null indicates the default should be used

getSharedInstance

public static LayoutStyle getSharedInstance()

Factory methods for obtaining the current LayoutStyle object appropriate for the current look and feel.

Returns:

the current LayoutStyle instance

getPreferredGap

public int getPreferredGap(Component component1,
                           Component component2,
                           int type,
                           int position,
                           Container parent)

Returns the amount of space to use between two components. The return value indicates the distance to place component2 relative to component1. For example, the following returns the amount of space to place between component2 and component1 when component2 is placed vertically above component1:

   int gap = getPreferredGap(component1, component2,
                             LayoutStyle.RELATED,
                             SwingConstants.NORTH, parent);
 

The type parameter indicates the type of gap being requested. It can be one of the following values:

RELATED	If the two components will be contained in the same parent and are showing similar logically related items, use RELATED.
UNRELATED	If the two components will be contained in the same parent but show logically unrelated items use UNRELATED.
INDENT	Used to obtain the preferred distance to indent a component relative to another. For example, if you want to horizontally indent a JCheckBox relative to a JLabel use INDENT. This is only useful for the horizontal axis.

It's important to note that some look and feels may not distinguish between RELATED and UNRELATED.

The return value is not intended to take into account the current size and position of component2 or component1. The return value may take into consideration various properties of the components. For example, the space may vary based on font size, or the preferred size of the component.

Parameters:

component1 - the JComponent component2 is being placed relative to

component2 - the JComponent being placed

type - how the two components are being placed

position - the position component2 is being placed relative to component1; one of SwingConstants.NORTH, SwingConstants.SOUTH, SwingConstants.EAST or SwingConstants.WEST

parent - the parent of component2; this may differ from the actual parent and may be null

Returns:

the amount of space to place between the two components

Throws:

IllegalArgumentException - if position is not one of SwingConstants.NORTH, SwingConstants.SOUTH, SwingConstants.EAST or SwingConstants.WEST; type not one of INDENT, RELATED or UNRELATED; or component1 or component2 is null

getContainerGap

public int getContainerGap(Component component,
                           int position,
                           Container parent)

Returns the amount of space to position a component inside its parent.

Parameters:

component - the Component being positioned

position - the position component is being placed relative to its parent; one of SwingConstants.NORTH, SwingConstants.SOUTH, SwingConstants.EAST or SwingConstants.WEST

parent - the parent of component; this may differ from the actual parent and may be null

Returns:

the amount of space to place between the component and specified edge

Throws:

IllegalArgumentException - if position is not one of SwingConstants.NORTH, SwingConstants.SOUTH, SwingConstants.EAST or SwingConstants.WEST; or component is null