布局管理简单认识

 

1.BorderLayout

   把界面划分为东、南、西、北、中五个部分

   若想添加更多的组件，可以建立多个panel,然后再panel中创建组件

   默认把组件放在Center方向

import java.awt.Button;import java.awt.Frame;public class TestBoderLayout extends Frame{public TestBoderLayout(){add(new Button("East"),"East");add(new Button("West"),"West");add(new Button("Center"),"Center");add(new Button("North"),"North");add(new Button("South"),"South");}public static void main(String[] args) {TestBoderLayout mainFrame = new TestBoderLayout();mainFrame.setTitle("BorderLayout");mainFrame.setSize(300,200);mainFrame.setVisible(true);}}

2. FlowLayout

它是panel面板中默认的布局管理器

如果一行放不下，就会放到下一行放置

public class TestBoderLayout extends Frame{public TestBoderLayout(){setLayout(new FlowLayout());add(new Button("East"));add(new Button("West"));add(new Button("Center"));add(new Button("North"));add(new Button("South"));}public static void main(String[] args) {TestBoderLayout mainFrame = new TestBoderLayout();mainFrame.setTitle("FlowLayout");mainFrame.setSize(300,200);mainFrame.setVisible(true);}} 

 

3.GridLayout

   将容器划分为若干行列的网格，在容器中添加组件时，它们会按从左到右，从上到下的顺序在网格中排列，需要指定在容器上划分的网格的行列数

4.CardLayout

   可以将多个组件放在同一个容器区域内交替显示，相当于多张卡片摞在一起，只有最上面的一张可见

   import java.awt.*;import java.awt.event.*;public class TestCardLayout extends Frame{Panel plWest = new Panel();Panel plCenter = new Panel();CardLayout cl = new CardLayout();public TestCardLayout(){plWest.setLayout(new GridLayout(3,1));Button btnPrev = new Button("prev");Button btnNext = new Button("next");Button btnThree = new Button("three");plWest.add(btnPrev);plWest.add(btnNext);plWest.add(btnThree);plCenter.setLayout(cl);plCenter.add(new Button("one"),"1");plCenter.add(new Button("two"),"2");plCenter.add(new Button("three"),"3");plCenter.add(new Button("four"),"4");plCenter.add(new Button("five"),"5");class MyActionListener implements ActionListener{public void actionPerformed(ActionEvent e){if(e.getActionCommand().equals("prev")){ cl.previous(plCenter);;}else if(e.getActionCommand().equals("next")){cl.next(plCenter);}else{cl.show(plCenter,"3");}}}add(plWest,"West");add(plCenter);MyActionListener ma = new MyActionListener();btnPrev.addActionListener(ma);btnNext.addActionListener(ma);btnThree.addActionListener(ma);}public static void main(String[] args) {TestCardLayout mainFrame = new TestCardLayout();mainFrame.setTitle("CardLayout");mainFrame.setSize(300,200);mainFrame.setVisible(true);}} 

5.GridBagLayout

   布局管理器之王...

6.取消容器上布局管理器

   Container.setLayout(null)取消布局管理器设置

   Component.setBounds方法来设置每个组件的大小和位置

   取消布局管理器，改变窗口大小，组件的大小不会适应窗口的改变

   import java.awt.*;import java.awt.event.*;public class TestCancelLayout extends Frame{public TestCancelLayout(){setLayout(null);Button b1 = new Button("第一个按钮");Button b2 = new Button("第二个按钮");b1.setBounds(10,30,80,30);b2.setBounds(60,70,100,20);add(b1);add(b2);}public static void main(String[] args) {TestCancelLayout mainFrame = new TestCancelLayout();mainFrame.setSize(300,200);mainFrame.setVisible(true);}}