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// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "avatarExample.h"
#include <QQmlEngine>
#include <QQmlComponent>
#include <QGuiApplication>
struct Expectations
{
QQmlEngine engine;
void expectOne()
{
//![1]
QQmlComponent component(&engine, "qrc:/exampleOne.qml");
QObject *object = component.create();
// The scarce resource will have been released automatically
// by this point, after the binding expression was evaluated.
bool expectedResult = (object->property("avatarWidth").toInt() == 100);
delete object;
//![1]
Q_ASSERT(expectedResult);
}
void expectTwo()
{
//![2]
QQmlComponent component(&engine, "qrc:/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]
Q_ASSERT(expectedResult);
}
void expectThree()
{
//![3]
QQmlComponent component(&engine, "qrc:/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]
Q_ASSERT(expectedResult);
}
void expectFour()
{
//![4]
QQmlComponent component(&engine, "qrc:/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]
Q_ASSERT(expectedResultOne);
Q_ASSERT(expectedResultTwo);
}
void expectFive()
{
//![5]
QQmlComponent component(&engine, "qrc:/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]
Q_ASSERT(expectedResultOne);
Q_ASSERT(expectedResultTwo);
}
};
int main(int argc, char *argv[])
{
QGuiApplication app(argc, argv);
Expectations expectations;
expectations.expectOne();
expectations.expectTwo();
expectations.expectThree();
expectations.expectFour();
expectations.expectFive();
}
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