FileChooser的使用,并且可以进行类型的过滤

java 代码

package example;

import java.io.File;

import javax.swing.filechooser.FileFilter;

public class SimpleFileFilter extends FileFilter {

    String[] extensions;

    String description;

    public SimpleFileFilter(String ext) {
        this(new String[] { ext }, null);
    }

    public SimpleFileFilter(String[] exts, String descr) {
        // Clone and lowercase the extensions
        extensions = new String[exts.length];
        for (int i = exts.length - 1; i >= 0; i--) {
            extensions[i] = exts[i].toLowerCase();
        }
        // Make sure we have a valid (if simplistic) description.
        description = (descr == null ? exts[0] + " files" : descr);
    }

    public boolean accept(File f) {
        // We always allow directories, regardless of their extensions.
        if (f.isDirectory()) {
            return true;
        }

        // It's a regular file, so check the extension.
        String name = f.getName().toLowerCase();
        for (int i = extensions.length - 1; i >= 0; i--) {
            if (name.endsWith(extensions[i])) {
                return true;
            }
        }
        return false;
    }

    public String getDescription() {
        return description;
    }

}

java 代码

package example;

import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class MyFilterChooser extends JFrame {
      public MyFilterChooser( ) {
        super("Filter Test Frame");
        setSize(350, 200);
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        Container c = getContentPane( );
        c.setLayout(new FlowLayout( ));

        JButton openButton = new JButton("Open");
        final JLabel statusbar = new JLabel("Output of your selection will go here");

        openButton.addActionListener(new ActionListener( ) {
          public void actionPerformed(ActionEvent ae) {
            String[] pics = new String[] {"gif", "jpg", "tif"};
            String[] audios = new String[] {"au", "aiff", "wav"};
            JFileChooser chooser = new JFileChooser( );
            chooser.addChoosableFileFilter(new SimpleFileFilter(pics,
                                           "Images (*.gif, *.jpg, *.tif)"));
            chooser.addChoosableFileFilter(new SimpleFileFilter(".MOV"));
            chooser.addChoosableFileFilter(new SimpleFileFilter(audios,
                                           "Sounds (*.aiff, *.au, *.wav)"));
            int option = chooser.showOpenDialog(MyFilterChooser.this);
            if (option == JFileChooser.APPROVE_OPTION) {
              if (chooser.getSelectedFile( )!=null)
                statusbar.setText("You chose " + chooser.getSelectedFile( ).getName( ));
            }
            else {
              statusbar.setText("You canceled.");
            }
          }
        });

        c.add(openButton);
        c.add(statusbar);
        setVisible(true);
      }

      public static void main(String args[]) {
        MyFilterChooser mfc = new MyFilterChooser( );
      }
    }