1 class Demo07GridBagLayout { 2 void makeButton(String s, JFrame frame, GridBagLayout gbLayout, GridBagConstraints gbConstraints) { 3 JButton button = new JButton(s); 4 gbLayout.setConstraints(button, gbConstraints); 5 frame.add(button); 6 } 7 public void run() { 8 JFrame frame = new JFrame("第七个GUI程序 -> 拨号盘"); 9 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 10 frame.setBounds(200, 300, 300, 160); 11 GridBagLayout gbLayout = new GridBagLayout(); // 创建GirdBagLayout布局管理器 12 GridBagConstraints gbConstraints = new GridBagConstraints(); 13 frame.setLayout(gbLayout); // 使用GirdBagLayout布局管理器 14 gbConstraints.fill = GridBagConstraints.BOTH; // 组件填充显示区域 15 gbConstraints.weightx = 0.0; // 恢复默认值 16 gbConstraints.gridwidth = GridBagConstraints.REMAINDER; // 结束行 17 JTextField textField = new JTextField("13612345678"); 18 gbLayout.setConstraints(textField, gbConstraints); 19 frame.add(textField); 20 gbConstraints.weightx = 0.5; // 指定分配区域 21 gbConstraints.weighty = 0.2; 22 gbConstraints.gridwidth = 1; 23 makeButton("7", frame, gbLayout, gbConstraints); // 调用方法，添加按钮 24 makeButton("8", frame, gbLayout, gbConstraints); 25 gbConstraints.gridwidth = GridBagConstraints.REMAINDER; // 结束行 26 makeButton("9", frame, gbLayout, gbConstraints); 27 gbConstraints.gridwidth = 1; // 重置gridwidth 28 makeButton("4", frame, gbLayout, gbConstraints); 29 makeButton("5", frame, gbLayout, gbConstraints); 30 gbConstraints.gridwidth = GridBagConstraints.REMAINDER; 31 makeButton("6", frame, gbLayout, gbConstraints); 32 gbConstraints.gridwidth = 1; 33 makeButton("1", frame, gbLayout, gbConstraints); 34 makeButton("2", frame, gbLayout, gbConstraints); 35 gbConstraints.gridwidth = GridBagConstraints.REMAINDER; 36 makeButton("3", frame, gbLayout, gbConstraints); 37 gbConstraints.gridwidth = 1; 38 makeButton("返回", frame, gbLayout, gbConstraints); 39 gbConstraints.gridwidth = GridBagConstraints.REMAINDER; 40 makeButton("拨号", frame, gbLayout, gbConstraints); 41 // gbConstraints.gridwidth = 1; 42 frame.setVisible(true); // 设置窗格可见 43 } 44 } 45 46 class E { 47 public static void main(String args[]) { 48 new Demo07GridBagLayout().run(); // 为什么第一列会比较宽 49 } 50 }
