It's OK now!

Qt Code:
  1. MainWindow::MainWindow(QWidget* parent):
  2. QMainWindow(parent)
  3. {
  4. ...
  5. this->setWindowFlags(Qt::WindowMinimizeButtonHint | Qt::FramelessWindowHint);
  6. this->setAttribute(Qt::WA_TranslucentBackground, false); //< Can't set translucentBackground true
  7. m_hwnd = this->viewPage->winId();
  8. ...
  9. }
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Although play properly, but I want set QMainWindow's style sheet (border-radius:8px).
How should I do?