键绑定与setMnemonic，setDisplayedMnemonic和setLabelFor

Question

I feel like a kid in a candy store--in trying yet again to get a handle on key bindings I stumbled onto setMnemonic() (in Netbeans form designer and its ton of generated code) and [especially!] the setDisplayedMnemonic() / setActionFor() pair (from Googling "can jlabel have mnemonic"), which seems a godsend.

All I know is that the following code just made my latest app a whole lot more user friendly in that it has rendered mouse/touchpad unnecessary.

btnRemoveScratchWords.setMnemonic(VK_C);
btnSearch.setMnemonic(VK_H);
btnClearOutput.setMnemonic(VK_O);
btnExit.setMnemonic(VK_X);
btnHelp.setMnemonic(VK_H);

lblPattern.setDisplayedMnemonic(VK_P);
lblPattern.setLabelFor(txtPattern);

lblLegal.setDisplayedMnemonic(VK_L);
lblLegal.setLabelFor(txtLegal);

lblMust.setDisplayedMnemonic(VK_R);
lblMust.setLabelFor(txtRequiredLetters);

lblMinimumPointsPerLetter.setDisplayedMnemonic(VK_R);
lblMinimumPointsPerLetter.setLabelFor(txtMinScore);

But is key bindings a better way to do this?

Answer 1

I'm gonna answer my own question. If I've made any errors or misinterpreted or misinformed, I hope to find out from someone. Question in advance: Did I mess anything up below?

Key bindings provide the only way to do some things. For instance...

I needed a keypress to cause the bottom line of a textarea to be displayed regardless of which component has the focus and to then select the contents of the 'main' textbox.

The statements below link the physical F2 keypress to a logical button on the form, whose action will be defined in a class (named JumpToEndOfOutput ) that extends AbstractAction , as required by getActionMap .

   txaOutput.getInputMap(WHEN_IN_FOCUSED_WINDOW).put(getKeyStroke("F2"),
                                "jumpToEndOfOutput");
   txaOutput.getActionMap().put("jumpToEndOfOutput", jumpToEndOfOutput);

(note use of WHEN_IN_FOCUSED_WINDOW , without which F2 can't always do what's needed):

// in constructor for form... make action listener for button

   btnJumpToEndOfOutput.addActionListener( new ButtonListener() );

...

// inner class avoids anonymous inner class, for clarity

    class ButtonListener implements ActionListener // simulates click of logical form button
    {
        public void actionPerformed( ActionEvent bp )
        {    
          txaOutput.selectAll();
          txtPattern.grabFocus();
          txtPattern.select(0, 99);
        } 
    } 

...

// back to constructor... make action object to listen for F2 keystroke

      JumpToEndOfOutput jumpToEndOfOutput = new JumpToEndOfOutput();

...

// class required for getActionMap

   class JumpToEndOfOutput extends AbstractAction // catches physical F2 keystroke
    {
        public void actionPerformed(ActionEvent e) 
        {
           btnJumpToEndOfOutput.doClick(); 
        } 
    }

Is there a shorter way to accomplish this?