swing 学习笔记九（选项卡 JApplet是japplet的扩展）

/**
* 选项卡 JApplet是japplet的扩展
*
* @time 9:09:33 AM
* @author retacn yue
* @Email [e-mail]
*/
public class Test_JtabedPaneTest extends JApplet {


private static final long serialVersionUID = 1L;
// 选项组件
private JTabbedPane tp = new JTabbedPane(SwingConstants.BOTTOM);
// 下接列表组件
private JComboBox combo = new JComboBox();


/**
* 构造器
*/
public Test_JtabedPaneTest() {
// 容器在线
Container container = getContentPane();


// 三个面板
JPanel comboPanel = new JPanel();
JPanel panelOne = new JPanel();
JPanel panelTwo = new JPanel();


// 中间显示面板中的按钮控件
panelOne.add(new JButton("当前选中的是第1个选项卡"));
panelOne.setBackground(Color.cyan);


panelTwo.add(new JButton("当前选中的是第2个选项卡"));
panelTwo.setBackground(Color.orange);


// 将两个tab页添加到选项组件
tp.add(panelOne, "Panel One");
tp.add(panelTwo, "Panel Two");


// 下拉列表
combo.addItem("TOP");
combo.addItem("LEFT");
combo.addItem("RIGHT");
combo.addItem("BOOTOM");


// 设置下拉列表的选中值
setComboValue();


comboPanel.add(new JLabel("选项卡的位置:"));
comboPanel.add(combo);


// 将下拉列表和选项卡两个组件添加到容器中
container.setLayout(new BorderLayout());
container.add(comboPanel, BorderLayout.NORTH);
container.add(tp, BorderLayout.CENTER);


combo.addItemListener(new ItemListener() {


public void itemStateChanged(ItemEvent e) {
// 发生事件的对象
JComboBox comboBox = (JComboBox) e.getSource();
// 返回更改值
int state = e.getStateChange();
// 当前选中
if (state == ItemEvent.SELECTED) {
String selectItemText = (String) comboBox.getSelectedItem();
// 根据下拉列表的选中值设置选项卡的位置
if (selectItemText.equals("TOP")) {
tp.setTabPlacement(JTabbedPane.TOP);
}
if (selectItemText.equals("LEFT")) {
tp.setTabPlacement(JTabbedPane.LEFT);
}
if (selectItemText.equals("RIGHT")) {
tp.setTabPlacement(JTabbedPane.RIGHT);
}
if (selectItemText.equals("BOTTOM")) {
tp.setTabPlacement(JTabbedPane.BOTTOM);
}
// 验证,再次布置其子组件
tp.validate();


}
}


});


}


/**
* 设置下拉列表的选中值
*/
private void setComboValue() {
int placement = tp.getTabPlacement();
String selectedItem = null;


switch (placement) {
case JTabbedPane.TOP:
selectedItem = "TOP";
break;
case JTabbedPane.LEFT:
selectedItem = "LEFT";
break;
case JTabbedPane.RIGHT:
selectedItem = "RIGHT";
break;
case JTabbedPane.BOTTOM:
selectedItem = "BOTTOM";
break;
}
combo.setSelectedItem(selectedItem);


}
}