javax.swing.plaf.basic
Class BasicBorders.MarginBorder

java.lang.Object
  extended by javax.swing.border.AbstractBorder
      extended by javax.swing.plaf.basic.BasicBorders.MarginBorder
All Implemented Interfaces:
Serializable, Border, UIResource
Enclosing class:
BasicBorders

public static class BasicBorders.MarginBorder
extends AbstractBorder
implements Serializable, UIResource

An invisible, but spacing border whose margin is determined by calling the getMargin() method of the enclosed component. If the enclosed component has no such method, this border will not occupy any space.

[An illustration that shows how MarginBorder
 determines its borders]

See Also:
Serialized Form

Constructor Summary
BasicBorders.MarginBorder()
          Constructs a new MarginBorder.
 
Method Summary
 Insets getBorderInsets(Component c)
          Measures the width of this border.
 Insets getBorderInsets(Component c, Insets insets)
          Determines the insets of this border by calling the getMargin() method of the enclosed component.
 
Methods inherited from class javax.swing.border.AbstractBorder
getInteriorRectangle, getInteriorRectangle, isBorderOpaque, paintBorder
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

BasicBorders.MarginBorder

public BasicBorders.MarginBorder()
Constructs a new MarginBorder.

Method Detail

getBorderInsets

public Insets getBorderInsets(Component c)
Measures the width of this border.

Specified by:
getBorderInsets in interface Border
Overrides:
getBorderInsets in class AbstractBorder
Parameters:
c - the component whose border is to be measured.
Returns:
an Insets object whose left, right, top and bottom fields indicate the width of the border at the respective edge.
See Also:
getBorderInsets(java.awt.Component, java.awt.Insets)

getBorderInsets

public Insets getBorderInsets(Component c,
                              Insets insets)
Determines the insets of this border by calling the getMargin() method of the enclosed component. The resulting margin will be stored into the the left, right, top and bottom fields of the passed insets parameter.

Unfortunately, getMargin() is not a method of JComponent or some other common superclass of things with margins. While reflection could be used to determine the existence of this method, this would be slow on many virtual machines. Therefore, the current implementation knows about AbstractButton.getMargin(), JPopupMenu.getMargin(), JToolBar.getMargin(), and JTextComponent. If c is an instance of a known class, the respective getMargin() method is called to determine the correct margin. Otherwise, a zero-width margin is returned.

Overrides:
getBorderInsets in class AbstractBorder
Parameters:
c - the component whose border is to be measured.
insets - an instance that will be overwritten and returned as the result (null not permitted).
Returns:
the same object that was passed for insets, but with changed fields.
See Also:
AbstractBorder.getBorderInsets(Component)