wasm: add secondary thread exec manual test

Pick-to: 6.3
Change-Id: Id16cddd703682d325d77ad597996960a8f521d1c
Reviewed-by: Lorn Potter <lorn.potter@gmail.com>

tests/manual/wasm/eventloop/CMakeLists.txt

@@ -1,6 +1,7 @@
 add_subdirectory(asyncify_exec)
 add_subdirectory(main_exec)
 add_subdirectory(main_noexec)
+add_subdirectory(thread_exec)
 if(QT_FEATURE_widgets)
 add_subdirectory(dialog_exec)
 endif()

tests/manual/wasm/eventloop/README.md

@@ -11,3 +11,4 @@ Contents
     main_exec       Standard Qt main(), where QApplication::exec() does not return
     main_noexec     Qt main() without QApplication::exec()
     dialog_exec     Shows how QDialog::exec() also does not return
+    thread_exec     Shows how to use QThread::exec()

tests/manual/wasm/eventloop/thread_exec/CMakeLists.txt

@@ -0,0 +1,8 @@
+qt_internal_add_manual_test(thread_exec
+    GUI
+    SOURCES
+        main.cpp
+    PUBLIC_LIBRARIES
+        Qt::Core
+        Qt::Gui
+)

tests/manual/wasm/eventloop/thread_exec/main.cpp

@@ -0,0 +1,122 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, 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 The Qt Company Ltd 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 <QtGui>
+
+class EventTarget : public QObject
+{
+    Q_OBJECT
+protected:
+    bool event(QEvent *evt)
+    {
+        if (evt->type() == QEvent::User) {
+            qDebug() << "User event on thread" << QThread::currentThread();
+            return true;
+        }
+        return QObject::event(evt);
+    }
+};
+
+class EventPosterWindow: public QRasterWindow
+{
+public:
+    EventPosterWindow(EventTarget *target)
+        :m_target(target)
+        { }
+
+    void paintEvent(QPaintEvent *ev) override {
+        QPainter p(this);
+        p.fillRect(ev->rect(), QColorConstants::Svg::deepskyblue);
+        p.drawText(50, 100, "Application has started. Click to post events.\n See the developer tools console for debug output");
+    }
+
+    void mousePressEvent(QMouseEvent *) override {
+        qDebug() << "Posting events from thread" << QThread::currentThread();
+        QGuiApplication::postEvent(m_target, new QEvent(QEvent::User));
+        QTimer::singleShot(500, m_target, []() {
+            qDebug() << "Timer event on secondary thread" << QThread::currentThread();
+        });
+    }
+
+public:
+    EventTarget *m_target;
+};
+
+class SecondaryThread : public QThread
+{
+public:
+    void run() override {
+        qDebug() << "exec on secondary thread" << QThread::currentThread();
+        exec();
+    }
+};
+
+// This example demonstrates how to start a secondary thread event loop
+int main(int argc, char **argv)
+{
+    QGuiApplication app(argc, argv);
+
+    EventTarget eventTarget;
+
+    EventPosterWindow window(&eventTarget);
+    window.show();
+
+    SecondaryThread thread;
+    eventTarget.moveToThread(&thread);
+
+#if QT_CONFIG(thread)
+    thread.start();
+#else
+    qDebug() << "Warning: This test requires a multithreaded build of Qt for WebAssembly";
+#endif
+
+    return app.exec();
+}
+
+#include "main.moc"