toolbardemo.java

学习参考,java基本语法练习,包括一些常用的技巧

//工具栏应用演示
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.net.URL;
public class ToolBarDemo extends JFrame implements ActionListener
{
	JMenuBar mbMain;
	JMenu mnuSystem,mnuHelp;
	JMenuItem mnuiCls,mnuiSave,mnuiClock,mnuiExit,mnuiContent,mnuiIndex,mnuiAbout;
	public ToolBarDemo()
	{
	    super("工具栏应用演示");
	    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   	    Font fntDisp1=new Font("宋体",Font.PLAIN,12);
	    mbMain=new JMenuBar();
	    mnuSystem=new JMenu("系统(S)");
	    mnuHelp=new JMenu("帮助(H)");
	    mnuSystem.setMnemonic('S');
	    mnuHelp.setMnemonic(KeyEvent.VK_H);
		mbMain.add(mnuSystem);
		mbMain.add(mnuHelp);
		mnuiCls=new JMenuItem("清除屏幕显示");
		mnuiSave=new JMenuItem("保存聊天记录");
		mnuiClock=new JMenuItem("查看时间");
		mnuiExit=new JMenuItem("退出系统");
		mnuiExit.addActionListener(this);
		mnuSystem.add(mnuiCls);
		mnuSystem.add(mnuiSave);
		mnuSystem.add(mnuiClock);
		mnuSystem.add(mnuiExit);
	    mnuSystem.setFont(fntDisp1);		
	    mnuHelp.setFont(fntDisp1);		
		mnuiCls.setFont(fntDisp1);		
		mnuiSave.setFont(fntDisp1);
		mnuiClock.setFont(fntDisp1);
		mnuiExit.setFont(fntDisp1);
		Icon icnContent=new ImageIcon("help.gif");
		mnuiContent=new JMenuItem("目录",icnContent);
		mnuiIndex=new JMenuItem("索引");
		mnuiAbout=new JMenuItem("关于[HappyChat聊天系统]...");
		mnuiAbout.addActionListener(this);
		mnuiContent.setFont(fntDisp1);
		mnuiIndex.setFont(fntDisp1);		
		mnuiAbout.setFont(fntDisp1);
		mnuHelp.add(mnuiContent);
		mnuHelp.add(mnuiIndex);
		mnuHelp.add(mnuiAbout);
		setJMenuBar(mbMain);
		//构造工具栏
		JToolBar tb=new JToolBar();
		//添加按钮到工具栏
		JButton btnNew=null;
		btnNew=makeButton("new","NEW","新建一个文件","新建");
		tb.add(btnNew);
		JButton btnOpen=null;
		btnOpen=makeButton("open","OPEN","打开一个文件","打开");
		tb.add(btnOpen);
		JButton btnSave=null;
		btnSave=makeButton("save","SAVE","保存一个文件","保存");
		tb.add(btnSave);
		JPanel pnlMain=new JPanel(new BorderLayout());
		setContentPane(pnlMain);
		pnlMain.add(tb,BorderLayout.PAGE_START);
		
		setSize(250,150);
		setVisible(true);
	} 
	public void actionPerformed(ActionEvent ae)
	{
		JOptionPane.showMessageDialog(null,"您选择了:"+ae.getActionCommand());
		if (ae.getSource()==mnuiExit)
			System.exit(0);
	}
	//构造工具栏按钮方法
	JButton makeButton(String strImage,String strAction,String txtToolTip,String strAlter) 
	{
        //搜索图片
        String imgLocation = strImage+ ".gif";
        URL urlImage = ToolBarDemo.class.getResource(imgLocation);
        //初始化工具按钮
        JButton btnTemp = new JButton();
        //设置按钮的命令
        btnTemp.setActionCommand(strAction);
        //设置提示信息
        btnTemp.setToolTipText(txtToolTip);
        btnTemp.addActionListener(this);
        if (urlImage != null)                       //找到图像
            btnTemp.setIcon(new ImageIcon(urlImage));
        else                                      //没有图像
            btnTemp.setText(strAlter);
        return btnTemp;
    }
    public static void main(String args[])
    {
    	new ToolBarDemo();
    }
}