1 /* 2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.javafx.scene.canvas; 27 28 import com.sun.javafx.scene.NodeHelper; 29 import com.sun.javafx.sg.prism.NGNode; 30 import com.sun.javafx.util.Utils; 31 import javafx.scene.Node; 32 import javafx.scene.canvas.Canvas; 33 34 /** 35 * Used to access internal methods of Canvas. 36 */ 37 public class CanvasHelper extends NodeHelper { 38 private static final CanvasHelper theInstance; 39 private static CanvasAccessor canvasAccessor; 40 41 static { 42 theInstance = new CanvasHelper(); 43 Utils.forceInit(Canvas.class); 44 } 45 46 private static CanvasHelper getInstance() { 47 return theInstance; 48 } 49 50 public static void initHelper(Canvas canvas) { 51 setHelper(canvas, getInstance()); 52 } 53 54 @Override 55 protected NGNode createPeerImpl(Node node) { 56 return canvasAccessor.doCreatePeer(node); 57 } 58 59 @Override 60 protected void updatePeerImpl(Node node) { 61 super.updatePeerImpl(node); 62 canvasAccessor.doUpdatePeer(node); 63 } 64 65 public static void setCanvasAccessor(final CanvasAccessor newAccessor) { 66 if (canvasAccessor != null) { 67 throw new IllegalStateException(); 68 } 69 70 canvasAccessor = newAccessor; 71 } 72 73 public interface CanvasAccessor { 74 NGNode doCreatePeer(Node node); 75 void doUpdatePeer(Node node); 76 } 77 78 }