Why FilenameFilter is never working?

[piulitza]

While coding in Java, I did many programs with GUI at which I needed to save something to a file. I usually use FileDialog to save something. Sometimes I wanted to filter the names of files that I wanted to see, so I tried to use FilenameFilter. But I never managed to make it working. Usually, I do like that:

package mainPack;
 
import java.awt.*;
import java.awt.event.*;
import java .io .*;
 
public class FerPrinc1 extends Frame implements ActionListener {
 
	public static void main(String[] args) {
		FerPrinc1 f1 = new FerPrinc1("Testare");
		f1.show();
	}
 
 
	FerPrinc1(String  titlu)
	{
		super(titlu);
		this.addWindowListener(new WindowAdapter()
		{
			public void windowClosing(WindowEvent e)
			{
				dispose();
			}
 
		});
		Button b1 = new Button ("Alege fisier");
		add(b1, BorderLayout.CENTER);
		pack();
		b1.addActionListener(this);
	}
 
 
 
 
 
 
	public void actionPerformed(ActionEvent e) {
		FileDialog fd = new FileDialog(this, "Alege fisier", FileDialog.LOAD);
 
		fd.setFilenameFilter(new FilenameFilter()
		{
 
			@Override
			public boolean accept(File dir, String numeFis) {
 
				return (numeFis.endsWith(".txt"));
			}
 
		});
		fd.show();
		setTitle("Fisierul ales este"+fd.getFile());
 
	}
 
 
 
 
}

The piece of code with the FilenameFilter is this one:

fd.setFilenameFilter(new FilenameFilter()
{

@Override
public boolean accept(File dir, String numeFis) {

return (numeFis.endsWith(".txt"));
}

});

As I told you, I never seen this working. Any clue what I am doing wrong? Is it any problems with using this on windows 8? Or what ?

[javapenguin]

Define "not working". Not compiling or not running like you want?

setTitle("Fisierul ales este"+fd.getFile());

It's loading the file. However, it lets me load .java files too.

Also, not sure what this means exactly, but it says on the FileDialog 7 API that, for setFilenameFilter()

"Sets the filename filter for this file dialog window to the specified filter. Filename filters do not function in Sun's reference implementation for Microsoft Windows."

You could always try JFileChooser instead of FileDialog.

[piulitza]

By not working I mean for example if i set the Loading FilenameFilter with ".txt", it will not show only .txt files as I wanted, it still shows all files in the folder!!!

[javapenguin]

Actually, unless I'm mistaken, what it's doing, though it isn't printing out true or false like I had it do to see if it was using the filter, which is a mystery, I think all that filter is doing is saying whether or not the selected File is of that type of extension or not.

Here's what the API says:

boolean accept(File dir,
String name)

Tests if a specified file should be included in a file list.

Parameters:
dir - the directory in which the file was found.
name - the name of the file.
Returns:
true if and only if the name should be included in the file list; false otherwise.

I wonder if this is what you were looking for:

File filters with JFileChooser

If you go the JFileChooser route, then addChooseableFileFilter() might be what you're after.

You'd have to make a subclass of FileFilter to do that.

Also, you could have more than one file filter I think that way too, as long as you had more than one subclass of FileFilter.

I must confess that I don't know how to add a file filter to a FileDialog.

[Norm]

Try using the JFileChooser class. Its API doc has an example of filtering.