mypopup.java

实例精华

/**
*<DL><DT><b>功能：</b><DD>awt演示---PopupMenu</DD></DL>
*/
import java.awt.*;
import java.awt.event.*;
public class MyPopup extends Frame
{
	PopupMenu p;
	MenuItem mi1,mi2,mi3,mi4;
	TextField t;
	public MyPopup()
	{
		super("Popup Menu");
		setLayout(new FlowLayout());
		t=new TextField(20);
		p = new PopupMenu(); 

		p.add(mi1=new MenuItem("View Source"));

		//add ActionListener for each Menu Item
		mi1.addActionListener(new miActionListener());

		p.addSeparator();//分隔符
		p.add(mi2=new MenuItem("Print"));
		mi2.addActionListener(new miActionListener());
		p.add(mi3=new MenuItem("Refresh"));
		mi3.addActionListener(new miActionListener());
		p.addSeparator();
		p.add(mi4=new MenuItem("Properties"));
		mi4.addActionListener(new miActionListener());
		//add the PopupMenu to the Frame
		add(p);
		add(t);
		//Enable the mouse event
		enableEvents(AWTEvent.MOUSE_EVENT_MASK);//AWTEvent.MOUSE_EVENT_MASK用于选择鼠标事件的事件掩码。 	
		pack();
		setVisible(true);
		show();
	}
	//Process the mouse event (Right click here)
	//这个方法是自动调用的，第当enableEvents(AWTEvent.MOUSE_EVENT_MASK);定义后，会自动的找到
	//	public void processMouseEvent(MouseEvent e)这个方法来调用
   	public void processMouseEvent(MouseEvent e)
	{
		if (e.isPopupTrigger())//返回此鼠标事件是否为该平台的弹出菜单触发事件。
		{
			//第一个参数指定的是点击右键后出现的菜单，第二个第三个参数是设置显示点击右键后出现菜单的坐标
			p.show(e.getComponent(),e.getX(),e.getY());
		}		
	}
	//MenuItem Action Listener
	class miActionListener implements ActionListener
	{
		public void actionPerformed(ActionEvent e)
		{			
			t.setText(e.getActionCommand());			
		}
	}
	
	public static void main(String args[])
	{
		MyPopup pu=new MyPopup();
		pu.setSize(300,300);
	}
}