/**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of the documentation of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** You may use this file under the terms of the BSD license as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names ** of its contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "avatarExample.h" #include #include void registerTypes() { //![0] qmlRegisterType("Qt.example", 1, 0, "AvatarExample"); //![0] } void expectOne() { //![1] QQmlComponent component(&engine, "exampleOne.qml"); QObject *object = component.create(); // The scarce resource will have been released automatically // by this point, after the binding expression was evaluated. delete object; //![1] } void expectTwo() { //![2] QQmlComponent component(&engine, "exampleTwo.qml"); QObject *object = component.create(); // The scarce resource will not have been released automatically // after the binding expression was evaluated. // Since the scarce resource was not released explicitly prior // to the binding expression being evaluated, we get: bool expectedResult = (object->property("avatar").isValid() == true); delete object; //![2] } void expectThree() { //![3] QQmlComponent component(&engine, "exampleThree.qml"); QObject *object = component.create(); // The resource was preserved explicitly during evaluation of the // JavaScript expression. Thus, during property assignment, the // scarce resource was still valid, and so we get: bool expectedResult = (object->property("avatar").isValid() == true); // The scarce resource will not be released until all references to // the resource are released, and the JavaScript garbage collector runs. delete object; //![3] } void expectFour() { //![4] QQmlComponent component(&engine, "exampleFour.qml"); QObject *object = component.create(); // The scarce resource was explicitly preserved by the client during // the importAvatar() function, and so the scarce resource // remains valid until the explicit call to releaseAvatar(). As such, // we get the expected results: bool expectedResultOne = (object->property("avatarOne").isValid() == true); bool expectedResultTwo = (object->property("avatarTwo").isValid() == false); // Because the scarce resource referenced by avatarTwo was released explicitly, // it will no longer be consuming any system resources (beyond what a normal // JS Object would; that small overhead will exist until the JS GC runs, as per // any other JavaScript object). delete object; //![4] } void expectFive() { //![5] QQmlComponent component(&engine, "exampleFive.qml"); QObject *object = component.create(); // We have the expected results: bool expectedResultOne = (object->property("avatarOne").isValid() == false); bool expectedResultTwo = (object->property("avatarTwo").isValid() == false); // Because although only avatarTwo was explicitly released, // avatarOne and avatarTwo were referencing the same // scarce resource. delete object; //![5] }