001/* PopupMenuUI.java -- 002 Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package javax.swing.plaf; 040 041import java.awt.event.MouseEvent; 042 043import javax.swing.JPopupMenu; 044import javax.swing.Popup; 045import javax.swing.PopupFactory; 046 047/** 048 * An abstract base class for delegates that implement the pluggable 049 * look and feel for a <code>JPopupMenu</code>. 050 * 051 * @see javax.swing.JPopupMenu 052 * 053 * @author Andrew Selkirk (aselkirk@sympatico.ca) 054 * @author Sascha Brawer (brawer@dandelis.ch) 055 */ 056public abstract class PopupMenuUI extends ComponentUI 057{ 058 /** 059 * Constructs a new <code>PopupMenuUI</code>. 060 */ 061 public PopupMenuUI() 062 { 063 // Nothing to do here. 064 } 065 066 067 /** 068 * Tests whether or not a mouse event triggers a popup menu. 069 * 070 * <p>The default implementation calls 071 * <code>event.isPopupTrigger()</code>, which checks for the gesture 072 * that is common for the platform on which the application runs. If 073 * a look and feel wants to employ non-standard conventions for 074 * triggering a popup menu, it can override this method. 075 * 076 * @param event the event to check. 077 * 078 * @return <code>true</code> if the event triggers a popup menu; 079 * <code>false</code> otherwise. 080 * 081 * @since 1.3 082 */ 083 public boolean isPopupTrigger(MouseEvent event) 084 { 085 return event.isPopupTrigger(); 086 } 087 088 089 /** 090 * Creates a <code>Popup</code> for displaying the popup menu. The 091 * default implementation uses the {@link javax.swing.PopupFactory} 092 * for retrieving a suitable <code>Popup</code>, but subclasses 093 * might want to override this method if a LookAndFeel needs special 094 * Popups. 095 * 096 * @param popup the <code>JPopupMenu</code> for whose display 097 * a <code>Popup</code> is needed. 098 * 099 * @param x the horizontal position where the popup will be 100 * displayed. 101 * 102 * @param y the vertical position where the popup will be 103 * displayed. 104 * 105 * @return a <code>Popup</code> for showing and hiding 106 * the menu. 107 * 108 * @since 1.4 109 */ 110 public Popup getPopup(JPopupMenu popup, int x, int y) 111 { 112 return PopupFactory.getSharedInstance().getPopup( 113 /* origin/owner of the popup */ popup.getInvoker(), 114 /* contents */ popup, 115 x, y); 116 } 117}