站内搜索: 请输入搜索关键词
当前页面: 在线文档首页 > JDK 5 Documentation v6.0, Java 2 SDK 英文文档

LayoutStyle (Java Platform SE 6) - JDK 5 Documentation v6.0, Java 2 SDK 英文文档


Java™ Platform
Standard Ed. 6

javax.swing
Class LayoutStyle

java.lang.Object
  extended by javax.swing.LayoutStyle

public abstract class LayoutStyle
extends Object

LayoutStyle provides information about how to position components. This class is primarily useful for visual tools and layout managers. Most developers will not need to use this class.

You typically don't set or create a LayoutStyle. Instead use the static method getInstance to obtain the current instance.

Since:
1.6

Nested Class Summary
static class LayoutStyle.ComponentPlacement
          ComponentPlacement is an enumeration of the possible ways two components can be placed relative to each other.
 
Constructor Summary
LayoutStyle()
          Creates a new LayoutStyle.
 
Method Summary
abstract  int getContainerGap(JComponent component, int position, Container parent)
          Returns the amount of space to place between the component and specified edge of its parent.
static LayoutStyle getInstance()
          Returns the shared instance of LayoutStyle.
abstract  int getPreferredGap(JComponent component1, JComponent component2, LayoutStyle.ComponentPlacement type, int position, Container parent)
          Returns the amount of space to use between two components.
static void setInstance(LayoutStyle style)
          Sets the shared instance of LayoutStyle.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

LayoutStyle

public LayoutStyle()
Creates a new LayoutStyle. You generally don't create a LayoutStyle. Instead use the method getInstance to obtain the current LayoutStyle.

Method Detail

setInstance

public static void setInstance(LayoutStyle style)
Sets the shared instance of LayoutStyle. Specifying null results in using the LayoutStyle from the current LookAndFeel.

Parameters:
style - the LayoutStyle, or null
See Also:
getInstance()

getInstance

public static LayoutStyle getInstance()
Returns the shared instance of LayoutStyle. If an instance has not been specified in setInstance, this will return the LayoutStyle from the current LookAndFeel.

Returns:
the shared instance of LayoutStyle
See Also:
LookAndFeel.getLayoutStyle()

getPreferredGap

public abstract int getPreferredGap(JComponent component1,
                                    JComponent component2,
                                    LayoutStyle.ComponentPlacement 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,
                             ComponentPlacement.RELATED,
                             SwingConstants.NORTH, parent);
 
The type parameter indicates the relation between the two components. If the two components will be contained in the same parent and are showing similar logically related items, use RELATED. If the two components will be contained in the same parent but show logically unrelated items use UNRELATED. Some look and feels may not distinguish between the RELATED and UNRELATED types.

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
position - the position component2 is being placed relative to component1; one of SwingConstants.NORTH, SwingConstants.SOUTH, SwingConstants.EAST or SwingConstants.WEST
type - how the two components are being placed
parent - the parent of component2; this may differ from the actual parent and it may be null
Returns:
the amount of space to place between the two components
Throws:
NullPointerException - if component1, component2 or type is null
IllegalArgumentException - if position is not one of SwingConstants.NORTH, SwingConstants.SOUTH, SwingConstants.EAST or SwingConstants.WEST
Since:
1.6
See Also:
LookAndFeel.getLayoutStyle()

getContainerGap

public abstract int getContainerGap(JComponent component,
                                    int position,
                                    Container parent)
Returns the amount of space to place between the component and specified edge of its parent.

Parameters:
component - the JComponent 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

Java™ Platform
Standard Ed. 6

Submit a bug or feature
For further API reference and developer documentation, see Java SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Copyright 2006 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.