java图形界面设计

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);

}

}

转自：http://blog.sina.com.cn/s/blog_616e189f0100ne1t.html