AWT BorderLayout

介绍

BorderLayout类排列的组成部分，以适应在五个区域：东部，西部，北部，南部和中心。每个区域只能包含一个组件，每个组件在每个区域确定相应的固定 NORTH, SOUTH, EAST, WEST和CENTER.

类的声明

以下是声明的java.awt.BorderLayout类：

public class BorderLayout
   extends Object
      implements LayoutManager2, Serializable

字段域

下面是java.awt.BorderLayout类的字段：

• static String AFTER_LAST_LINE -- Synonym for PAGE_END.

• static String AFTER_LINE_ENDS -- Synonym for LINE_END.

• static String BEFORE_FIRST_LINE -- Synonym for PAGE_START.

• static String BEFORE_LINE_BEGINS -- Synonym for LINE_START.

• static String CENTER -- The center layout constraint (middle of container).

• static String EAST -- The east layout constraint (right side of container).

• static String LINE_END -- The component goes at the end of the line direction for the layout.

• static String LINE_START -- The component goes at the beginning of the line direction for the layout.

• static String NORTH -- The north layout constraint (top of container).

• static String PAGE_END -- The component comes after the last line of the layout's content.

• static String PAGE_START -- The component comes before the first line of the layout's content.

• static String SOUTH -- The south layout constraint (bottom of container).

• static String WEST -- The west layout constraint (left side of container).

类的构造函数

类方法

继承的方法

这个类继承的方法从以下类：

• java.lang.Object

BorderLayout 实例

选择使用任何编辑器创建以下java程序 D:/ > AWT > com > zaixian > gui >

package com.zaixian.gui;

import java.awt.*;
import java.awt.event.*;

public class AwtLayoutDemo {
   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;
   private Label msglabel;

   public AwtLayoutDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AwtLayoutDemo  awtLayoutDemo = new AwtLayoutDemo();  
      awtLayoutDemo.showBorderLayoutDemo();       
   }
      
   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      msglabel = new Label();
      msglabel.setAlignment(Label.CENTER);
      msglabel.setText("Welcome to TutorialsPoint AWT Tutorial.");

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showBorderLayoutDemo(){
      headerLabel.setText("Layout in action: BorderLayout");      

      Panel panel = new Panel();
      panel.setBackground(Color.darkGray);
      panel.setSize(300,300);
      BorderLayout layout = new BorderLayout();
      layout.setHgap(10);
      layout.setVgap(10);
      panel.setLayout(layout);        
	  
      panel.add(new Button("Center"),BorderLayout.CENTER);
      panel.add(new Button("Line Start"),BorderLayout.LINE_START); 
      panel.add(new Button("Line End"),BorderLayout.LINE_END);
      panel.add(new Button("East"),BorderLayout.EAST);   
      panel.add(new Button("West"),BorderLayout.WEST); 
      panel.add(new Button("North"),BorderLayout.NORTH); 
      panel.add(new Button("South"),BorderLayout.SOUTH); 

      controlPanel.add(panel);

      mainFrame.setVisible(true);  
   }
}

编译程序，使用命令提示符。进入到D:/> AWT，然后键入以下命令。

D:AWT>javac comzaixianguiAwtlayoutDemo.java

如果没有错误出现，这意味着编译成功。使用下面的命令来运行程序。

D:AWT>java com.zaixian.gui.AwtlayoutDemo

验证下面的输出