jlabeltest.java

详细讲解了java的基础知识

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.border.*;
public class JLabelTest extends JApplet
{
JLabel jLabel1=new JLabel("Mac Performa6400",
	new ImageIcon("Mac.gif"),
	SwingConstants.CENTER);
JPanel jPanel1=new JPanel(true);
JPanel jPanel2=new JPanel(true);
JPanel jPanel3=new JPanel(true);
JPanel jPanel4=new JPanel();
JPanel jPanel5=new JPanel();
JRadioButton jrb1[]=new JRadioButton[6];
JRadioButton jrb2[]=new JRadioButton[6];
String labelText[]={"上","中","下","左", "中间","右"};
ButtonGroup btng1=new ButtonGroup();
ButtonGroup btng2=new ButtonGroup();
ButtonGroup btng3=new ButtonGroup();
ButtonGroup btng4=new ButtonGroup();
JLabel jlbl1=new JLabel("Icon-Text间距");
JCheckBox jcb1=new JCheckBox("标签使能");
JComboBox jcombo1=new JComboBox();

public void init(){
	for(int i=0;i<jrb1.length;i++){
		jrb1[i]=new JRadioButton(labelText[i]);
		jrb2[i]=new JRadioButton(labelText[i]);
			
		jPanel1.add(jrb1[i]);
		btng2.add(jrb2[i]);
		jPanel2.add(jrb2[i]);
		jrb1[i].addActionListener(new java.awt.event.ActionListener() {
       		public void actionPerformed(ActionEvent e) {
        		jrb1_actionPerformed(e);
      			}
    		});
		jrb2[i].addActionListener(new java.awt.event.ActionListener() {
       		public void actionPerformed(ActionEvent e) {
        		jrb2_actionPerformed(e);
      			}
    		});
		}
		
		btng1.add(jrb1[0]);
		btng1.add(jrb1[1]);
		btng1.add(jrb1[2]);
		btng2.add(jrb1[3]);
		btng2.add(jrb1[4]);
		btng2.add(jrb1[5]);
		jPanel1.setLayout(new GridLayout(2,3,0,0));
		jPanel1.setBorder(new TitledBorder("标签对齐方式"));
		
		btng3.add(jrb2[0]);
		btng3.add(jrb2[1]);
		btng3.add(jrb2[2]);
		btng4.add(jrb2[3]);
		btng4.add(jrb2[4]);
		btng4.add(jrb2[5]);
		jPanel2.setLayout(new GridLayout(2,3,0,0));
		jPanel2.setBorder(new TitledBorder("标签文字位置"));
		
		jPanel3.add(jlbl1);
		jcombo1.addItem("5");
		jcombo1.addItem("10");
		jcombo1.addItem("20");
		jcombo1.addItem("50");
		jcombo1.setPreferredSize(new Dimension(50,20));
		jcombo1.setVisible(true);
		jcombo1.setEditable(true);
		jPanel3.add(jcombo1);
		jPanel3.add(jcb1);
		jPanel3.setLayout(new FlowLayout());
		jPanel4.add(jPanel1);
		jPanel4.add(jPanel2);
		//jPanel4.add(jPanel3);
		jPanel4.setLayout(new FlowLayout());
		this.getContentPane().add(jPanel4,BorderLayout.NORTH);
		this.getContentPane().add(jPanel3,BorderLayout.SOUTH);
		
		jPanel5.add(jLabel1,BorderLayout.CENTER);
		jPanel5.setBorder(new TitledBorder(""));
		jPanel5.setLayout(new GridLayout(1,1,0,0));
		this.getContentPane().add(jPanel5,BorderLayout.CENTER);
		
		jcombo1.addItemListener(new ItemListener() {
			public void itemStateChanged(ItemEvent event) {
				
				String    s = (String)jcombo1.getSelectedItem();
				int       icon_text_gap = Integer.parseInt(s);				
				jLabel1.setIconTextGap( icon_text_gap);
			}
		});
		
		jcb1.setSelected(true);
		jcb1.addActionListener(new java.awt.event.ActionListener() {
       				public void actionPerformed(ActionEvent e) {
        				jLabel1.setEnabled(jcb1.isSelected());
      				}
    		});
		
		
		
	}
	
	void jrb1_actionPerformed(ActionEvent e) {
  	  	String command= e.getActionCommand();
		if (command=="左")
		{jLabel1.setHorizontalAlignment(SwingConstants.LEFT);}
		if (command=="中间")
		{jLabel1.setHorizontalAlignment(SwingConstants.CENTER);}
		if (command=="右")
		{jLabel1.setHorizontalAlignment(SwingConstants.RIGHT);}
		if (command=="上")
		{jLabel1.setVerticalAlignment(SwingConstants.TOP);}
		if (command=="中")
		{jLabel1.setVerticalAlignment(SwingConstants.CENTER);}
		if (command=="下")
		{jLabel1.setVerticalAlignment(SwingConstants.BOTTOM);}

  	}
		void jrb2_actionPerformed(ActionEvent e) {
  	  	String command= e.getActionCommand();
		if (command=="左")
		{jLabel1.setHorizontalTextPosition(SwingConstants.LEFT);}
		if (command=="中间")
		{jLabel1.setHorizontalTextPosition(SwingConstants.CENTER);}
		if (command=="右")
		{jLabel1.setHorizontalTextPosition(SwingConstants.RIGHT);}
		if (command=="上")
		{jLabel1.setVerticalTextPosition(SwingConstants.TOP);}
		if (command=="中")
		{jLabel1.setVerticalTextPosition(SwingConstants.CENTER);}
		if (command=="下")
		{jLabel1.setVerticalTextPosition(SwingConstants.BOTTOM);}


  	}

}