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copied!<p><strong>Edit:</strong> rework of entire post to cover basics as well.</p> <p><code>Background.h</code>:</p> <pre><code>#ifndef BACKGROUND_H #define BACKGROUND_H #include <QThread> #include <QObject> class Background : public QThread { Q_OBJECT public: Background(QObject* parent = 0):QThread(parent){} protected: void run() { qDebug(qPrintable(QString("Child function ran in thread: %1").arg(QThread::currentThreadId()))); } }; class BackgroundConcurrent : public QObject { Q_OBJECT public: BackgroundConcurrent(QObject* parent = 0):QObject(parent){} public slots: void doWork() const { qDebug(qPrintable(QString("Concurrent child function ran in thread: %1").arg(QThread::currentThreadId()))); } }; class BackgroundTrigger : public QObject { Q_OBJECT public: BackgroundTrigger(QObject* parent = 0):QObject(parent){} ~BackgroundTrigger() { foreach(QObject* child, children()) { QThread* childThread = qobject_cast<QThread*>(child); if (childThread) childThread->wait(); } } public slots: void triggerWorker() { Background* child = new Background(this); child->start(); } }; #endif // BACKGROUND_H </code></pre> <p><code>main.cpp</code>:</p> <pre><code>#include "Background.h" #include <QCoreApplication> #include <QtConcurrentRun> int main(int argc, char *argv[]) { QCoreApplication a(argc, argv); // Using QThread BackgroundTrigger childTrigger; qDebug(qPrintable(QString("Main function ran in thread: %1").arg(QThread::currentThreadId()))); // Call child childTrigger.triggerWorker(); childTrigger.triggerWorker(); // Using QtConcurrent BackgroundConcurrent cchild; QFuture<void> future1 = QtConcurrent::run(&cchild, &BackgroundConcurrent::doWork); QFuture<void> future2 = QtConcurrent::run(&cchild, &BackgroundConcurrent::doWork); return 0; } </code></pre> <p>Sample output:</p> <pre>Main function ran in thread: 1087038064 Child function ran in thread: 1091267472 Child function ran in thread: 1093417872 Concurrent child function ran in thread: 1095519120 Concurrent child function ran in thread: 1097644944</pre> <p>Be sure you run moc on your header files, <a href="http://doc.trolltech.com/4.5/qmake-manual.html" rel="nofollow noreferrer">qmake</a> and <a href="http://www.cmake.org/cmake/help/documentation.html" rel="nofollow noreferrer">cmake</a> both support creating your makefiles.</p> <p>Here is the <code>CMakeLists.txt</code> file I used to build the code:</p> <pre><code>cmake_minimum_required(VERSION 2.6) #Project name project(TEST) #Use Qt4 find_package(Qt4) if(QT4_FOUND) set(QT_USE_QTOPENGL TRUE) include(${QT_USE_FILE}) set(LIBS ${QT_LIBRARIES} ) #Source files (*.cpp, *.o) set(TEST_SRCS main.cpp) #Header files (*.h[pp]) set(TEST_HDRS Background.h) #Qt macros to handle uic, moc, etc... QT4_WRAP_CPP(TEST_MOC ${TEST_HDRS} OPTIONS -nw) set(TEST_ALLSRC ${TEST_SRCS} ${TEST_MOC}) #Create main add_executable(test ${TEST_ALLSRC}) target_link_libraries(test ${LIBS}) endif(QT4_FOUND) </code></pre>

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