【转】java图形界面设计(AWT)
【转自】http://blog.sina.com.cn/s/blog_616e189f0100ne1t.html
1. 基本的java Frame操作。
Java的图形界面的类主要包括AWT和Swing。在AWT中图形元素的父类为Component。
继承关系如下:Component->Container->Window->Frame->JFrame。(注意:Swing对AWT进行了扩展)。
下面给出一个简单的java图形程序:
package com.guan.visualTest.frameTest;
import java.awt.Button;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JFrame;
public class MainFrame {
public static void main(String[] args)
{
//创建frame
JFrame frame = new JFrame("welcome!!");
//调整frame的大小和初始位置
frame.setSize(400, 400);
frame.setLocation(100, 100);
//新建5个Button
Button button1 = new Button("hello1");
Button button2 = new Button("hello2");
Button button3 = new Button("hello3");
Button button4 = new Button("hello4");
Button button5 = new Button("hello5");
//将5个Button添加到frame中
frame.add(button1,"East");
frame.add(button2,"West");
frame.add(button3,"South");
frame.add(button4,"Center");
frame.add(button5,"North");
//增加窗口监听事件,使用内部类方法,并用监听器的默认适配器
frame.addWindowListener(new WindowAdapter(){
//重写窗口关闭事件
@Override
public void windowClosing(WindowEvent arg0) {
System.exit(0);
}
});
//显示窗体
frame.setVisible(true);
}
}
执行效果:
2. AWT的布局管理器
AWT中主要有四种布局管理器:FlowLayout、GridLayout、BorderLayout和CardLayout。
下面给出这四种布局管理器的源码:
package com.guan.visualTest.frameTest;
import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.CardLayout;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class YourFrame extends Frame{
private static final long serialVersionUID = 1L;
Panel borderLayoutPanel;
Panel cardLayoutPanel;
Panel flowLayoutPanel;
Panel gridLayoutPanel;
private void generateGridLayoutPanel() {
gridLayoutPanel = new Panel();
gridLayoutPanel.setLayout(new GridLayout(2,2));
Button button1 = new Button("button1");
Button button2 = new Button("button2");
Button button3 = new Button("button3");
Button button4 = new Button("button4");
gridLayoutPanel.add(button1);
gridLayoutPanel.add(button2);
gridLayoutPanel.add(button3);
gridLayoutPanel.add(button4);
}
private void generateFlowLayoutPanel() {
flowLayoutPanel = new Panel();
flowLayoutPanel.setLayout(new FlowLayout());
Button button1 = new Button("button1");
Button button2 = new Button("button2");
Button button3 = new Button("button3");
Button button4 = new Button("button4");
Button button5 = new Button("button5");
button1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
((Button)e.getSource()).setLabel("welcome ");
}
});
flowLayoutPanel.add(button1);
flowLayoutPanel.add(button2);
flowLayoutPanel.add(button3);
flowLayoutPanel.add(button4);
flowLayoutPanel.add(button5);
}
private void generateBorderLayoutPanel() {
borderLayoutPanel = new Panel();
borderLayoutPanel.setLayout(new BorderLayout());
Button button1 = new Button("South");
Button button2 = new Button("West");
Button button3 = new Button("East");
Button button4 = new Button("North");
Button button5 = new Button("Center");
borderLayoutPanel.add(button1,BorderLayout.SOUTH);
borderLayoutPanel.add(button2,BorderLayout.WEST);
borderLayoutPanel.add(button3,BorderLayout.EAST);
borderLayoutPanel.add(button4,BorderLayout.NORTH);
borderLayoutPanel.add(button5,BorderLayout.CENTER);
}
private void genrateCardLayoutPanel() {
cardLayoutPanel = new Panel();
final CardLayout cl = new CardLayout();
cardLayoutPanel.setLayout(cl);
Button button1 = new Button("black");
Button button2 = new Button("red");
ActionListener al = new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
cl.next(cardLayoutPanel);
}
};
button1.addActionListener(al);
button2.addActionListener(al);
cardLayoutPanel.add(button1,"1");
cardLayoutPanel.add(button2,"2");
}
public YourFrame(String panelName) {
super("panelName");
generateBorderLayoutPanel();
generateFlowLayoutPanel();
generateGridLayoutPanel();
genrateCardLayoutPanel();
setLayout(new GridLayout(2,2));
add(borderLayoutPanel);
add(flowLayoutPanel);
add(gridLayoutPanel);
add(cardLayoutPanel);
setSize(800, 800);
setLocation(100,100);
addWindowListener(new WindowAdapter(){
@Override
public void windowClosing(WindowEvent arg0) {
System.exit(0);
}
});
}
public static void main(String[] args) {
YourFrame yourFrame = new YourFrame("welcome");
yourFrame.setVisible(true);
}
}
运行结果:
3. 菜单栏的实现:
菜单栏关键的类包括MenuBar、Menu和MenuItem。下面给出测试代码:
package com.guan.visualTest.frameTest;
import java.awt.FileDialog;
import java.awt.Frame;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.TextArea;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
public class MenuFrame {
public static void main(String[] args) {
final Frame frame = new Frame();
frame.setSize(800,800);
frame.setLocation(100,100);
frame.addWindowListener(new WindowAdapter(){
@Override
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
final TextArea ta = new TextArea();
frame.add(ta);
//创建菜单栏
MenuBar mb = new MenuBar();
//创建菜单
Menu file = new Menu("File");
Menu edit = new Menu("Edit");
//创建菜单项
MenuItem mi1 = new MenuItem("Open");
//添加打开文件功能响应
mi1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
FileDialog fd = new FileDialog(frame,"打开文件",FileDialog.LOAD);
fd.setVisible(true);
String fileName = fd.getDirectory()+fd.getFile();
if(fileName != null)
{
try {
FileInputStream fis = new FileInputStream(fileName);
byte[] buf = new byte[10*1024];
try {
int len = fis.read(buf);
ta.append(new String(buf,0,len));
fis.close();
} catch (IOException e1) {
e1.printStackTrace();
}
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
}
}
});
MenuItem mi2 = new MenuItem("Save");
MenuItem mi3 = new MenuItem("Other Save");
MenuItem mi4 = new MenuItem("Close");
//添加 关闭响应
mi4.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
System.exit(0);
}
});
MenuItem mi5 = new MenuItem("Cope");
MenuItem mi6 = new MenuItem("Paste");
file.add(mi1);
file.add(mi2);
file.add(mi3);
file.add(mi4);
edit.add(mi5);
edit.add(mi6);
mb.add(file);
mb.add(edit);
frame.setMenuBar(mb);
frame.setVisible(true);
}
}
执行结果:
4. 最后Swing的简单测试
package com.guan.visualTest.frameTest;
import java.awt.BorderLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
public class SwingFrame {
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JButton button = new JButton("ok");
frame.getContentPane().add(button,BorderLayout.WEST);
frame.setSize(800,800);
frame.setLocation(100, 100);
frame.setVisible(true);
}
}