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POShowing/hiding a JPopupMenu from a JButton; FocusListener not working?
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copied!<p>I needed a JButton with an attached dropdown style menu. So I took a JPopupMenu and attached it to the JButton in the way you can see in the code below. What it needs to do is this: </p> <ul> <li>show the popup when clicked</li> <li>hide it if clicked a second time</li> <li>hide it if an item is selected in the popup</li> <li>hide it if the user clicks somewhere else in the screen</li> </ul> <p>These 4 things work, but because of the boolean flag I'm using, if the user clicks somewhere else or selects an item, I have to click twice on the button before it shows up again. That's why I tried to add a FocusListener (which is absolutely not responding) to fix that and set the flag false in these cases.</p> <p><strong>EDIT: Last attempt in an answer post...</strong></p> <p>Here are the listeners: (It's in a class extending JButton, so the second listener is on the JButton.)</p> <pre><code>// Show popup on left click. menu.addFocusListener(new FocusListener() { @Override public void focusLost(FocusEvent e) { System.out.println("LOST FOCUS"); isShowingPopup = false; } @Override public void focusGained(FocusEvent e) { System.out.println("GAINED FOCUS"); } }); addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { System.out.println("isShowingPopup: " + isShowingPopup); if (isShowingPopup) { isShowingPopup = false; } else { Component c = (Component) e.getSource(); menu.show(c, -1, c.getHeight()); isShowingPopup = true; } } }); </code></pre> <p>I've been fighting with this for way too long now. If someone can give me a clue about what's wrong with this, it would be great!</p> <p>Thanks!</p> <p><strong>Code:</strong></p> <pre><code>public class Button extends JButton { // Icon. private static final ImageIcon ARROW_SOUTH = new ImageIcon("ArrowSouth.png"); // Unit popup menu. private final JPopupMenu menu; // Is the popup showing or not? private boolean isShowingPopup = false; public Button(int height) { super(ARROW_SOUTH); menu = new JPopupMenu(); // menu is populated somewhere else // FocusListener on the JPopupMenu menu.addFocusListener(new FocusListener() { @Override public void focusLost(FocusEvent e) { System.out.println("LOST FOCUS"); isShowingPopup = false; } @Override public void focusGained(FocusEvent e) { System.out.println("GAINED FOCUS"); } }); // ComponentListener on the JPopupMenu menu.addComponentListener(new ComponentListener() { @Override public void componentShown(ComponentEvent e) { System.out.println("SHOWN"); } @Override public void componentResized(ComponentEvent e) { System.out.println("RESIZED"); } @Override public void componentMoved(ComponentEvent e) { System.out.println("MOVED"); } @Override public void componentHidden(ComponentEvent e) { System.out.println("HIDDEN"); } }); // ActionListener on the JButton addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { System.out.println("isShowingPopup: " + isShowingPopup); if (isShowingPopup) { menu.requestFocus(); isShowingPopup = false; } else { Component c = (Component) e.getSource(); menu.show(c, -1, c.getHeight()); isShowingPopup = true; } } }); // Skip when navigating with TAB. setFocusable(true); // Was false first and should be false in the end. menu.setFocusable(true); } } </code></pre>

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