JFileChooser not showing

Question

I have had a problem concerning the JFileChooser for a long while now and haven't been able to find help... The problem is that the file window is not showing up. I have tried to find the cause of this problem and I have tested the following:

public class Test {
   public static void main (String[] args) {   
   load();     
   }
   public static void load () {
      String folder = System.getProperty("user.dir");
      JFileChooser fc = new JFileChooser(folder);
      int resultat = fc.showOpenDialog(null);  
   }
}

When running this code I do get the window to show.

But, when I try this:

public class Test {
    public static void main (String[] args) {   
    String input = JOptionPane.showInputDialog(null, "Make your choice!\n" +
                                                     "1. load file");      
    load();   

    }
}

the window is not showing however, the programming is still running... I have no clue what might be causing this problem

Answer 1

Java on the Mac is really picky about Swing things only occurring in the Event Dispatch Thread. Try this.

import java.awt.EventQueue;
import javax.swing.JFileChooser;

public class Test {
    private static int result;
    public static void main(String[] args) throws Exception {
        EventQueue.invokeAndWait(new Runnable() {
            @Override
            public void run() {
                String folder = System.getProperty("user.dir");
                JFileChooser fc = new JFileChooser(folder);
                result = fc.showOpenDialog(null);
            }
        });
        System.out.println(result);
    }
}

Documentation for InvokeAndWait is here. But basically, you pass it a Runnable that does Swing stuff, and it will execute that in the right thread. There's also InvokeLater if you don't want to wait.