java布局 BorLayout布局

3、BorderLayout边界布局管理器



BorderLayout把容器分为东、南、西、北、中五个区域，每个组件将占据一个区域。这五个区域分别被命名为NORTH、WEST、EAST、SOUTH、CENTER，五个区域使用五个静态常量来标示。

常量	说明
public static final String NORTH=”North”	内容面板北边
public static final String WEST=”West”	内容面板西边
public static final String EAST=”East”	内容面板东边
public static final String CENTER=”Center”	内容面板中间
public static final String SOUTH=”South”	内容面板南边

案例1：完成如下图所示的窗口设计



public class SwingLayoutDemo {

private JFrame mainFrame;

private JLabel headerLabel;

private JLabel statusLabel;

private JPanel controlPanel;

private JLabel msglabel;

public SwingLayoutDemo(){

prepareGUI();

}

public static void main(String[] args){

SwingLayoutDemo swingLayoutDemo = new SwingLayoutDemo();

swingLayoutDemo.showBorderLayoutDemo();

}

private void prepareGUI(){

mainFrame = new JFrame("Java SWING Examples");

mainFrame.setSize(400,400);

mainFrame.setLayout(new GridLayout(3, 1));

headerLabel = new JLabel("",JLabel.CENTER );

statusLabel = new JLabel("",JLabel.CENTER);

statusLabel.setSize(350,100);

mainFrame.addWindowListener(new WindowAdapter() {

public void windowClosing(WindowEvent windowEvent){

System.exit(0);

}

});

controlPanel = new JPanel();

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");

JPanel panel = new JPanel();

panel.setBackground(Color.darkGray);

panel.setSize(300,300);

BorderLayout layout = new BorderLayout();

layout.setHgap(10);

layout.setVgap(10);

panel.setLayout(layout);

panel.add(new JButton("Center"),BorderLayout.CENTER);

panel.add(new JButton("Line Start"),BorderLayout.LINE_START);

panel.add(new JButton("Line End"),BorderLayout.LINE_END);

panel.add(new JButton("East"),BorderLayout.EAST);

panel.add(new JButton("West"),BorderLayout.WEST);

panel.add(new JButton("North"),BorderLayout.NORTH);

panel.add(new JButton("South"),BorderLayout.SOUTH);

controlPanel.add(panel);

mainFrame.setVisible(true);

} }