QDockWidget * dock3 = new QDockWidget(tr("DOCK3 TranslucentBackground"),
textEdit,Qt::FramelessWindowHint);
dock3->setAllowedAreas(Qt::LeftDockWidgetArea | Qt::RightDockWidgetArea);
//dock3->setWindowFlags(dock2->windowFlags()|Qt::FramelessWindowHint);
dock3->setAttribute(Qt::WA_TranslucentBackground);
//dock3->setAttribute(Qt::WA_NoSystemBackground);
{
QWidget* WindowRect = new QWidget(dock3);
QWidget* titleRect = new QLabel ("Title",WindowRect);
titleRect->setFixedSize(QSize(30,60));
titleRect->setStyleSheet("background:rgb(0,0,255);");
QWidget* ContentRect = new QLabel("Content",WindowRect);
ContentRect->setFixedSize(QSize(60,30));
ContentRect->setStyleSheet("background:rgb(0,255,0);");
QVBoxLayout* layout = new QVBoxLayout(WindowRect);
layout->addWidget(titleRect);
layout->addWidget(ContentRect);
dock3->setWidget(WindowRect);
}