Qt，类间通信

Question

I have two classes MainWindow and Worker . MainWindow is basically responsible for GUI and the worker is for connecting with the server. MainWindow has an instance of Worker . If Worker receives a message from the server it is supposed to change the GUI, but I can not find a way to communicate them. I thought about making MainWindow a singleton, and then use slots and signals. But maybe is there an easier way, like some function to get the object of the current View?

Answer 1

You mentioned signals/slots in your question, but you combined them with a singleton, which is not needed at all. You said MainWindow has an instance of Worker, so just connect to a signal from the Worker. Since you didn't provide any code, I'll make something up.

void Worker::doSomething()
{
    ...

    // When we get a message from the server emit a signal
    emit messageReceived();
}

...

MyWindow::MyWindow()
{
    auto worker = new Worker();

    // Connect to the Worker's signal
    connect(worker, &Worker::messageReceived, this, &MyWindow::handleMessage);

    worker->start();
}

void MyWindow::handleMessage()
{
    // The MainWindow can now do something in response to the server message
}