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The Java Developers Almanac 1.4Order this book from Amazon. |
e767. Determining When the Menu of a JComboBox Component Is Displayed// Create component String[] items = {"item1", "item2"}; JComboBox cb = new JComboBox(items); cb.setEditable(true); // Create and register listener MyPopupMenuListener actionListener = new MyPopupMenuListener(); cb.addPopupMenuListener(actionListener); class MyPopupMenuListener implements PopupMenuListener { // This method is called just before the menu becomes visible public void popupMenuWillBecomeVisible(PopupMenuEvent evt) { JComboBox cb = (JComboBox)evt.getSource(); } // This method is called just before the menu becomes hidden public void popupMenuWillBecomeInvisible(PopupMenuEvent evt) { JComboBox cb = (JComboBox)evt.getSource(); } // This method is called when menu is hidden because the user cancelled it public void popupMenuCanceled(PopupMenuEvent evt) { JComboBox cb = (JComboBox)evt.getSource(); } }
e757. Getting and Setting the Selected Item in a JComboBox Component e758. Getting the Items in a JComboBox Component e759. Adding and Removing an Item in a JComboBox Component e760. Selecting an Item in a JComboBox Component with Multiple Keystrokes e761. Determining If the Menu of a JComboBox Component Is Visible e762. Displaying the Menu in a JComboBox Component Using a Keystroke e763. Displaying the Menu in a JComboBox Component Using a Keystroke If the Selected Item Is Not Unique e764. Setting the Number of Visible Items in the Menu of a JComboBox Component e765. Listening for Changes to the Selected Item in a JComboBox Component e766. Listening for Action Events from a JComboBox Component © 2002 Addison-Wesley. |