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The Java Developers Almanac 1.4Order this book from Amazon. |
e614. Setting the Initial Focused Component in a WindowThere is no straightforward way to set the initial focused component in a window. The typical method is to add a window listener to listen for the window opened event and then make the desired component request the focus.// Create frame and three buttons JFrame frame = new JFrame(); JButton component1 = new JButton("1"); JButton component2 = new JButton("2"); JButton component3 = new JButton("3"); // Set component with initial focus; must be done before the frame is made visible InitialFocusSetter.setInitialFocus(frame, component2); class InitialFocusSetter { public static void setInitialFocus(Window w, Component c) { w.addWindowListener(new FocusSetter(c)); } public static class FocusSetter extends WindowAdapter { Component initComp; FocusSetter(Component c) { initComp = c; } public void windowOpened(WindowEvent e) { initComp.requestFocus(); // Since this listener is no longer needed, remove it e.getWindow().removeWindowListener(this); } } }
e607. Preventing a Component from Gaining the Focus e608. Preventing a Window from Gaining the Focus e609. Listening to All Focus Changes Between Components in an Application e610. Setting Focus Traversal Keys in a Component e611. Setting Focus Traversal Keys for the Entire Application e612. Moving the Focus to the Next or Previous Focusable Component e613. Modifying the Focus Traversal Order e615. Finding the Next Focusable Component e616. Determining If a Focus Lost Is Temporary or Permanent e617. Determining the Opposite Component of a Focus Event e618. Validating a JTextField When Permanently Losing the Focus e619. Removing the Focus from the Application e620. Activating a Keystroke When Any Component in the Window Has Focus e621. Activating a Keystroke When Any Child Component Has Focus
© 2002 Addison-Wesley. |