Package java.awt

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Class BorderLayout

public  class  java.awt.BorderLayout
    extends  java.lang.Object  
    implements java.awt.LayoutManager  
{
        // Constructors
    public BorderLayout();	
    public BorderLayout(int  hgap, int  vgap);	

        // Methods
    public void  addLayoutComponent(String  name,	
          Component  comp);
    public void layoutContainer(Container  target);	
    public Dimension minimumLayoutSize(Container  target);	
    public Dimension preferredLayoutSize(Container  target);	
    public void removeLayoutComponent(Component  comp);	
    public String toString();	
}

A border layout lays out a container using members named "North", "South", "East", "West", and "Center". The components get laid out according to their preferred sizes and the constraints of the container's size. The "North" and "South" components may be stretched horizontally; the "East" and "West" components may be stretched vertically; the "Center" component may stretch both horizontally and vertically to fill any space left over.

Here is an example of five buttons in an applet laid out using the BorderLayout layout manager:

The code for this applet is the following:

import java.awt.*;
import java.applet.Applet;

public class buttonDir extends Applet {
  public void init() {
    setLayout(new BorderLayout());
        add("North", new Button("North"));
    add("South", new Button("South"));
    add("East", new Button("East"));
    add("West", new Button("West"));
    add("Center", new Button("Center"));
  }
}

Constructors

BorderLayout

public BorderLayout() 

Constructs a new border layout.

BorderLayout

public BorderLayout(int  hgap, int  vgap) 

Creates a new border layout with the specified horizontal and vertical gaps. The horizontal and vertical gaps specify the space between the components.

Parameter	Description
hgap	the horizontal gap
vgap	the vertical gap

Methods

addLayoutComponent

public void addLayoutComponent(String  name, Component  comp) 

Adds the specified component to this border layout using the indicated tag.

For border layouts, the tag should be one of "North", "South", "East", "West", or "Center". Any other tag is ignored.

Most applications do not call this method directly. This method is called when a component is added to a container using the two-argument add method .

Parameter	Description
name	a tag understood by the layout manager
comp	the component to be added

layoutContainer

public void layoutContainer(Container  target) 

Lays out the container argument using this border layout.

This method reshapes the components in the specified container in order to satisfy the constraints of this BorderLayout object. The "North" and "South"components, if any, are placed at the top and bottom of the container, respectively. The "West" and "East" components are then placed on the left and right, respectively. Finally, the "Center" object is placed in any remaining space in the middle.

Most applications do not call this method directly. This method is called when a container calls its layout method .

Parameter	Description
target	the container in which to do the layout

See Also: Container .

minimumLayoutSize

public Dimension minimumLayoutSize(Container  target) 

Determines the minimum size of the target container using this layout manager.

This method is called when a container calls its minimumSize method . Most applications do not call this method directly.

Return Value:

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

Parameter	Description
target	the container in which to do the layout

See Also: Container preferredLayoutSize .

preferredLayoutSize

public Dimension preferredLayoutSize(Container  target) 

Determines the preferred size of the target container using this layout manager.

This method is called when a container calls its preferredSize method . Most applications do not call this method directly.

Return Value:

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

Parameter	Description
target	the container in which to do the layout

See Also: Container minimumLayoutSize .

removeLayoutComponent

public void removeLayoutComponent(Component  comp) 

Removes the specified component from this border layout. This method is called when a container calls its remove or removeAll methods. Most applications do not call this method directly.

Parameter	Description
comp	the component to be removed

toString

public String toString() 

Return Value:

Returns a string representation of this border layout.

Overrides:

toString in class Object .