JOptionPane传递自定义按钮

Question

I'm trying to get the value returned by custom buttons passed to JOptionPane. However the buttons I pass don't return a value at all. Only when the exit button is pressed is a value of -1 returned. I need this because I am changing the properties of the buttons enabled or disabled. I assume I need the buttons to return some information to the JOptionPane in some way. Any idea?

    JButton button1= new JButton("Button 1");
    JButton button2= new JButton("Button 2");

    button1.setEnabled(false);

    int value = JOptionPane.showOptionDialog(null, "Heres a test message", "Test", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, null, new Object[]{button1, button2}, button1);
    JOptionPane.showMessageDialog(null, "You entered " + value);

Nb This is related to my previous question - JOptionPane Grey Out One Button

I tried setting the value of the buttons like you said but they never return OK or CANCEL.

Whenever checking the value of the buttons, they never return the value I set them too.

    JButton button1= new JButton("Button1");
    JButton button2= new JButton("Button2");

    button1.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                JOptionPane pane = getOptionPane((JComponent)e.getSource());
                // set the value of the option pane
                pane.setValue(JOptionPane.OK_OPTION);
            }
        });

    button2.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                JOptionPane pane = getOptionPane((JComponent)e.getSource());
                // set the value of the option pane
                pane.setValue(JOptionPane.CANCEL_OPTION);
            }
        });

      if (JOptionPane.showOptionDialog(null, "Pick a button", "Pick", JOptionPane.OK_CANCEL_OPTION, JOptionPane.QUESTION_MESSAGE, null, new Object[]{button1, button2}, button1) == JOptionPane.OK_OPTION) {
           JOptionPane.showMessageDialog(null, "Button1");
      }
      else{
           JOptionPane.showMessageDialog(null, "Button2");
      }

See above, always I get the button2 popup no matter what.

Answer 1

In the example I linked to you previous question, the buttons use the JOptionPane#setValue method to set the return value. This allows you to continue using the API as normal, while providing you with the customisation your after.

            final JButton okay = new JButton("Ok");
            okay.addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    JOptionPane pane = getOptionPane((JComponent)e.getSource());
                    // set the value of the option pane
                    pane.setValue(JOptionPane.OK_OPTION);
                }
            });

Take a closer look at Disable ok button on JOptionPane.dialog until user gives an input

Updated

I've gone back through the code and correct the actionPerformed methods to enable it to return a valid value...

final JButton okay = new JButton("Ok");
okay.addActionListener(new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e) {
        JOptionPane pane = getOptionPane((JComponent)e.getSource());
        pane.setValue(okay);
    }
});
okay.setEnabled(false);
final JButton cancel = new JButton("Cancel");
cancel.addActionListener(new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e) {
        JOptionPane pane = getOptionPane((JComponent)e.getSource());
        pane.setValue(cancel);
    }
});

The value returned by the index of the value in the options array (last parameter)

So, for example...

int value = JOptionPane.showOptionDialog(
     null, 
     field, 
     "Get", 
     JOptionPane.YES_NO_OPTION, 
     JOptionPane.QUESTION_MESSAGE, 
     null, 
     new Object[]{okay, cancel}, 
     okay);

If the user clicks the okay button, the return value will be 0 , or if they select the cancel button, it will be 1

Answer 2

If you need this complex behavior, consider creating your own JDialog and then displaying it in a modal fashion.

If you have to use a JOptionPane, you can do this by extracting its JDialog and recursively iterating through its components til you find the one you want to disable and disable it:

import java.awt.Component;
import java.awt.Container;
import javax.swing.*;

public class Foo2 {
   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            doRun();
         }
      });
   }

   public static void doRun() {
      String[] options = {"Button 1", "Button 2", "Button 3"};

      JOptionPane myOptionPane = new JOptionPane("Heres a test message",
            JOptionPane.QUESTION_MESSAGE, JOptionPane.YES_NO_OPTION, 
            null, options, options[2]);
      JDialog myDialog = myOptionPane.createDialog(null, "My Test");
      myDialog.setModal(true);

      inactivateOption(myDialog, options[1]);

      myDialog.setVisible(true);
      Object result = myOptionPane.getValue();
      // Note: result might be null if the option is cancelled
      System.out.println("result: " + result);

      System.exit(0); // to stop Swing event thread
   }

   private static void inactivateOption(Container container, String text) {
      Component[] comps = container.getComponents();
      for (Component comp : comps) {
         if (comp instanceof AbstractButton) {
            AbstractButton btn = (AbstractButton) comp;
            if (btn.getActionCommand().equals(text)) {
               btn.setEnabled(false);
               return;
            }
         } else if (comp instanceof Container) {
            inactivateOption((Container) comp, text);
         }
      }

   }
}

However for myself, I'd just create a JDialog.

Answer 3

You don't have to define your buttons explicitly.

int result = JOptionPane.showOptionDialog(this, "Are you sure you want to...?", "Title", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, null, new String[] { "Yes", "No" }, JOptionPane.NO_OPTION);
if (result == JOptionPane.YES_OPTION) {
  ...
}