Spec-Zone .ru
спецификации, руководства, описания, API
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001/* 002 * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved. 003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 004 * 005 * This code is free software; you can redistribute it and/or modify it 006 * under the terms of the GNU General Public License version 2 only, as 007 * published by the Free Software Foundation. Oracle designates this 008 * particular file as subject to the "Classpath" exception as provided 009 * by Oracle in the LICENSE file that accompanied this code. 010 * 011 * This code is distributed in the hope that it will be useful, but WITHOUT 012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 014 * version 2 for more details (a copy is included in the LICENSE file that 015 * accompanied this code). 016 * 017 * You should have received a copy of the GNU General Public License version 018 * 2 along with this work; if not, write to the Free Software Foundation, 019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 020 * 021 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 022 * or visit www.oracle.com if you need additional information or have any 023 * questions. 024 */ 025 026package javafx.scene.layout; 027 028import java.util.Iterator; 029 030import javafx.scene.Node; 031import javafx.scene.Parent; 032 033import com.sun.javafx.WeakReferenceQueue; 034 035/** 036 * The base class for defining node-specific layout constraints. Region 037 * classes may create extensions of this class if they need to define their own 038 * set of layout constraints. 039 * 040 */ 041public abstract class ConstraintsBase { 042 043 /** 044 * If set as max value indicates that the pref value should be used as the max. 045 * This allows an application to constrain a resizable node's size, which normally 046 * has an unlimited max value, to its preferred size. 047 */ 048 public static final double CONSTRAIN_TO_PREF = Double.NEGATIVE_INFINITY; 049 050 WeakReferenceQueue impl_nodes = new WeakReferenceQueue(); 051 052 ConstraintsBase() { 053 } 054 055 void add(Node node) { 056 impl_nodes.add(node); 057 } 058 059 void remove(Node node) { 060 impl_nodes.remove(node); 061 } 062 063 /** 064 * Calls requestLayout on layout parent associated with this constraint object. 065 */ 066 protected void requestLayout() { 067 Iterator<Node> nodeIter = impl_nodes.iterator(); 068 while (nodeIter.hasNext()) { 069 Parent p = nodeIter.next().getParent(); 070 if (p != null) { 071 p.requestLayout(); 072 } 073 } 074 } 075}