Using StretchDIBits() in QWidget

[bear101]

Ah, I found the solution on page 417 in the QT book. It will work using something like this:

void MyWidget::paintEvent(QPaintEvent *p)
{
    QPainter painter(this);
    HWND hWnd = winId();
    HDC hdc = painter.paintEngine()->getDC();
    RECT r;
    r.left = this->rect().left()+50;
    r.top = this->rect().top()+50;
    r.right = this->rect().right();
    r.bottom = this->rect().bottom();
    int xx = ::DrawText(hdc, L"FOOOOOOOOOO", 5, &r, DT_VCENTER | DT_CENTER | DT_SINGLELINE);
    painter.paintEngine()->releaseDC(hdc);
}

void MyWidget::paintEvent(QPaintEvent *p)
{
    QPainter painter(this);
    HWND hWnd = winId();
    HDC hdc = painter.paintEngine()->getDC();
    RECT r;
    r.left = this->rect().left()+50;
    r.top = this->rect().top()+50;
    r.right = this->rect().right();
    r.bottom = this->rect().bottom();
    int xx = ::DrawText(hdc, L"FOOOOOOOOOO", 5, &r, DT_VCENTER | DT_CENTER | DT_SINGLELINE);
    painter.paintEngine()->releaseDC(hdc);
}

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[wysota]

Be aware this is not safe without proper preparations. Your paintEvent will be called to draw something to the backing store so you have to prevent that by using PaintOnScreen. And your application will behave slower, by the way but if you really need a DC context then there is no way to avoid that. You can obtain the same effect using Qt only calls without any downsides.