Re-open the book, see an example of a picture browser, run the code, re-understand the code, and paste the code directly
package awt;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import javax.swing.ImageIcon;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
public class ImageViewerFrame extends JFrame {
private JLabel label;
private JFileChooser chooser;
private static final int DEFAULT_WIDTH = 500;
private static final int DEFAULT_HEIGHT = 700;
public ImageViewerFrame() {
super();
setTitle("图片浏览-lihm");
setSize(this.DEFAULT_WIDTH,this.DEFAULT_HEIGHT);
label = new JLabel();
add(label);
this.chooser = new JFileChooser();//java提供的文件选择器
chooser.setCurrentDirectory(new File("."));//设置当前浏览路径
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu menu = new JMenu("文件");
menuBar.add(menu);
JMenuItem openItem = new JMenuItem("打开图片");
menu.add(openItem);
openItem.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
int result = chooser.showOpenDialog(null);//弹出文件选择对话框
if(result==JFileChooser.APPROVE_OPTION){
String name = chooser.getSelectedFile().getPath();
label.setIcon(new ImageIcon(name));
}
}
});
JMenuItem exitItem = new JMenuItem("退出");
menu.add(exitItem);
exitItem.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
System.exit(0);
}
});
}
}
The class where the main method is located:
package awt;
/**
* @author LIHM
* @time 2013-01-20
* @desc ImageViewer
*/
import java.awt.EventQueue;
import javax.swing.JFrame;
public class ImageViewer {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
//EventQueue 是一个与平台无关的类，它将来自于基础同位体类和受信任的应用程序类的事件列入队列
//invokeLater导致 runnable 的 run 方法在 EventQueue 的指派线程上被调用
EventQueue.invokeLater(new Runnable(){//此处使用Runnable的一个匿名对象
@Override
public void run() {
// TODO Auto-generated method stub
JFrame frame = new ImageViewerFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}
The effect is as follows:
click menu
Click to open the image to open the file view of the directory where the class is located
After selecting the file it shows:
The program does not compress and read the picture, but only displays a corner of the picture, and more processing can be done later.