Re: dynamic tool tip text

From:

Knute Johnson <nospam@rabbitbrush.frazmtn.com>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 17 Mar 2010 19:13:12 -0700

Message-ID:

<Y_fon.88480$K81.55349@newsfe18.iad>

On 3/17/2010 1:59 PM, Jim Janney wrote:

In Eclipse when you display a tool tip you get a different message if
the control or shift keys are pressed. I'm trying to do the same
thing in a Swing program. My first try was to subclass JTextField
and override getToolTipText(MouseEvent), something like this:

public class CustomTextField extends JTextField {
   // usual constructors

   @Override
   public String getToolTipText(MouseEvent event) {
     String result;
     if (event.isControlDown()&& getAlternateText() != null) {
       result = getAlternateText();
     } else {
       result = super.getToolTipText(event);
     }
     return result;
   }

   public String getAlternateText() {
      return "get your alternate text here";
   }
}

This works for text fields but it's hard to extend it to other kinds
of components. If you have a non-editable combo box the class that
receives the method call is some subclass of JButton, for example
com.jgoodies.looks.plastic.PlasticComboBoxButton: exactly which
one you get depends on the look and feel.

I'm wondering if this is the wrong approach and I should be doing
something with a MouseListener instead. Has anyone else done anything
like this?

I tried it with a MouseListener and it works fine.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class test extends JPanel {
     private boolean alt;

     public test() {
         super(new GridBagLayout());

         setPreferredSize(new Dimension(400,300));

         JButton b = new JButton("Press Me");
         b.addMouseListener(new MouseAdapter() {
             public void mouseEntered(MouseEvent me) {
                 JComponent c = (JComponent)me.getSource();
                 if (me.isAltDown())
                     c.setToolTipText("ALT is pressed");
                 else
                     c.setToolTipText("ALT isn't pressed!");

             }
         });
         add(b);
     }

     public static void main(String[] args) {
         EventQueue.invokeLater(new Runnable() {
             public void run() {
                 JFrame f = new JFrame();
                 f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                 test t = new test();
                 f.add(t);
                 f.pack();
                 f.setVisible(true);
             }
         });
     }
}

--

Knute Johnson
email s/nospam/knute2010/