e614. Setting the Initial Focused Component in a Window

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There 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);            }        }    }

 

Related Examples

e614. Setting the Initial Focused Component in a Window