如何使另一个线程拥有的对象的 canvas 无效？

Question

我想在单独的线程中加载数据，而不是调用 redraw 方法使 canvas 无效并绘制数据。但是，当我调用 redraw 方法时，它会触发断点并显示以下消息：

ASSERT failure in QCoreApplication::sendEvent: "Cannot send events to objects owned by different thread..."

我正在寻找可用于在正确线程中调用函数的某种分派方法。

Qt5 的正确方法是什么？

Answer 1

总体思路是将信号从工作线程发送回主线程，然后触发重绘。像这样的东西（我还没有测试过）：

class Worker : public QObject
{
    Q_OBJECT

public:
    ...
    void loadData()
    {
        ... // Do stuff

        emit dataLoaded();
    }
}

class MainWindow : public QObject
{
    Q_OBJECT

public:
    MainWindow()
    {
        Worker *worker = new Worker;
        worker->moveToThread(workerThread);
        connect(&workerThread, &QThread::started, worker, &Worker::loadData);
        connect(worker, &Worker::dataLoaded, this, &MainWindow::redraw);
        workerThread.start();
    }

public slots:
    void redraw()
    {
        // Do your redrawing here
    }

private:
    QThread workerThread;
}

如何使另一个线程拥有的对象的 canvas 无效？

How do I invalidate canvas of an object owned by another thread?

c++

qt

qt5