壹個java小程序

import java.awt.*;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.*;

public class FontTest implements ActionListener {

private JFrame frame;

private JComboBox jcb;

private JRadioButton jrb1,jrb2,jrb3;

private JPanel jp;

private JLabel text;

public FontTest(){

//容器

frame=new JFrame("字體測試");

frame.setSize(400, 300);

frame.setBackground(Color.GRAY);

//面板

jp=new JPanel();

jp.setPreferredSize(new Dimension(400,300));

frame.setContentPane(jp);

//默認字體

Font font=new Font("宋體", Font.PLAIN, 16);

//字大小

jcb=new JComboBox();

jcb.setToolTipText("選擇字體大小");

jcb.addItem("16");

jcb.addItem("18");

jcb.addItem("20");

jcb.addActionListener(this);

jcb.setPreferredSize(new Dimension(300,30));

jp.add(jcb);

//字風格

jrb1=new JRadioButton("PLAIN:普通",true);

jrb2=new JRadioButton("BOLD:加粗",false);

jrb3=new JRadioButton("ITALIC:傾斜",false);

jrb1.setPreferredSize(new Dimension(300,25));

jrb2.setPreferredSize(new Dimension(300,25));

jrb3.setPreferredSize(new Dimension(300,25));

jrb1.addActionListener(this);

jrb2.addActionListener(this);

jrb3.addActionListener(this);

jp.add(jrb1);

jp.add(jrb2);

jp.add(jrb3);

//文本

text=new JLabel();

text.setPreferredSize(new Dimension(300,40));

text.setFont(font);

text.setText("這些文字用來實時顯示字體大小和風格");

text.setForeground(Color.RED);

jp.add(text);

//設置可見、設置可退出

frame.setVisible(true);

frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);

}

public void actionPerformed(ActionEvent e) {

if(e.getSource() instanceof JComboBox){

int index= jcb.getSelectedIndex();

int fontSize=16;

int style=text.getFont().getStyle();

if(index==1){

fontSize=18;

}else

if(index==2){

fontSize=20;

}

Font font=new Font("宋體",style,fontSize);

this.text.setFont(font);

text.repaint();

}else

if(e.getSource() instanceof JRadioButton){

int style=Font.PLAIN;

int fontSize=text.getFont().getSize();

JRadioButton jr=(JRadioButton)e.getSource();

if(jr.equals(jrb1)){

jrb1.setSelected(true);

jrb2.setSelected(false);

jrb3.setSelected(false);

style=Font.PLAIN;

}else

if(jr.equals(jrb2)){

jrb2.setSelected(true);

jrb1.setSelected(false);

jrb3.setSelected(false);

style=Font.BOLD;

}else

if(jr.equals(jrb3)){

jrb3.setSelected(true);

jrb1.setSelected(false);

jrb2.setSelected(false);

style=Font.ITALIC;

}

Font font=new Font("宋體",style,fontSize);

this.text.setFont(font);

}

}

public static void main(String[] args) {

new FontTest();

}

}