How to Set Focus on JTextField?

Question

I make my game run without mouse so using pointer is not a choice. High Score menu will show when player lose.

this is my code

    highScore=new MyTextField("Your Name");
    highScore.addKeyListener(this);
    highScore.setFont(font);
    highScore.requestFocusInWindow();

I have tried

highScore.setFocusable(true);
highScore.requestFocusInWindow();
highScore.requestFocus(true);
highScore.requestFocus();

but still not gained focus on my JTextField.

How to focus it?

Answer 1

While yourTextField.requestFocus() is A solution, it is not the best since in the official Java documentation this is discourage as the method requestFocus() is platform dependent.

The documentation says:

Note that the use of this method is discouraged because its behavior is platform dependent. Instead we recommend the use of requestFocusInWindow().

Use yourJTextField.requestFocusInWindow() instead.

Answer 2

If you want your JTextField to be focused when your GUI shows up, you can use this:

in = new JTextField(40);
f.addWindowListener( new WindowAdapter() {
    public void windowOpened( WindowEvent e ){
        in.requestFocus();
    }
}); 

Where f would be your JFrame and in is your JTextField.

Answer 3

If the page contains multiple item and like to set the tab sequence and focus I will suggest to use FocusTraversalPolicy.

grabFocus() will not work if you are using FocusTraversalPolicy.

Sample code

int focusNumber = 0;
Component[] focusList;
focusList = new Component[] { game, move, amount, saveButton,
            printButton, editButton, deleteButton, newButton,
            settingsButton };

frame.setFocusTraversalPolicy(new FocusTraversalPolicy() {

        @Override
        public Component getLastComponent(Container aContainer) {
            return focusList[focusList.length - 1];
        }

        @Override
        public Component getFirstComponent(Container aContainer) {
            return focusList[0];
        }

        @Override
        public Component getDefaultComponent(Container aContainer) {
            return focusList[1];
        }

        @Override
        public Component getComponentAfter(Container focusCycleRoot,
                Component aComponent) {
            focusNumber = (focusNumber + 1) % focusList.length;
            if (focusList[focusNumber].isEnabled() == false) {
                getComponentAfter(focusCycleRoot, focusList[focusNumber]);
            }
            return focusList[focusNumber];
        }

        @Override
        public Component getComponentBefore(Container focusCycleRoot,
                Component aComponent) {
            focusNumber = (focusList.length + focusNumber - 1)
                    % focusList.length;
            if (focusList[focusNumber].isEnabled() == false) {
                getComponentBefore(focusCycleRoot, focusList[focusNumber]);
            }
            return focusList[focusNumber];
        }
    });

Answer 4

public void actionPerformed(ActionEvent arg0)
{
    if (arg0.getSource()==clearButton)
    {
        enterText.setText(null);
        enterText.grabFocus();  //Places flashing cursor on text box        
    }       
}

Answer 5

In my case nothing above worked untill I called requestFocus() AFTER my constructor has returned.

MyPanel panel = new MyPanel(...);
frame.add(panel);
panel.initFocus();

MyPanel.initFocus() would have:

myTextField.requestFocus();

And it works.

Answer 6

It was not working for me when tried to use:

JOptionPane.showConfirmDialog(...)

But - I found a solution ! Very primitive, but works.

Just jump to the field by java.awt.Robot using key "Tab". For example:

Robot robot = new Robot();
robot.keyPress(KeyEvent.VK_TAB);
robot.delay(100);
robot.keyRelease(KeyEvent.VK_TAB);

If you should press multiple times on "Tab" to get your Component you can use below method:

GUIUtils.pressTab(3);

Definition:

public static void pressTab(int amountOfClickes)
{
    SwingUtilities.invokeLater(new Runnable()
    {
        public void run()
        {
            try
            {
                Robot robot = new Robot();
                int i = amountOfClickes;
                while (i-- > 0)
                {
                    robot.keyPress(KeyEvent.VK_TAB);
                    robot.delay(100);
                    robot.keyRelease(KeyEvent.VK_TAB);
                }
            }
            catch (AWTException e)
            {
                System.out.println("Failed to use Robot, got exception: " + e.getMessage());
            }
        }
    });
}

If your Component location is dynamic, you can run over the while loop without limitation, but add some focus listener on the component, to stop the loop once arrived to it.