Thanks for your attention! I've read the Mandelbrot example which is just fit my problem. And the rendering thread pass a QImage object instead of a vector to the GUI thread. I followed this and solved my problem. It seems that it is more difficult to manage the vector.
Now I have a little problem. below is my rendering thread's run method.
void MyThread::run()
{
render(); // is this unblock?
exec();
}Because I have a QTimer,so I need to add the "exec()" at the bottom. but if the "render()" fuction is executed in block-mode. How can the rendering thread start its own event-loop when the render fuction is being executed? (But now ,it just works, the readering thread can receive the Timer's timeout signals,and then pass the QImage to the GUI thread!)