Hello. I am currently styling my application and there are things I would like to clear up. The following sample shows the window with the toolbar on the top. The toolbar contains a widget which is used in order to set custom buttons layout. The issue I noticed is the blue background of the toolbar still visible around the widget although I set margin and padding to zero. Here is the code:

Qt Code: 
  1. #include <QtGui>
  2.  
  3. class MainWindow: public QMainWindow
  4. {
  5. public:
  6. 	MainWindow();
  7. };
  8.  
  9. MainWindow::MainWindow()
  10. {
  11. 	QToolBar *toolbar = new QToolBar;
  12. 	toolbar->setObjectName("mainToolbar");
  13. 	toolbar->setMovable(false);
  14. 	toolbar->setFloatable(false);
  15. 	toolbar->setContentsMargins(0, 0, 0, 0);
  16.  
  17. 	QWidget *widg = new QWidget;
  18. 	widg->setObjectName("toolbarWidget");
  19. 	widg->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
  20.  
  21. 	QHBoxLayout *hlay = new QHBoxLayout;
  22.  
  23. 	QPushButton *btn1 = new QPushButton("Rosencrantz");
  24. 	QPushButton *btn2 = new QPushButton("Guildenstern");
  25.  
  26. 	hlay->addWidget(btn1);
  27. 	hlay->addWidget(btn2);
  28.  
  29. 	widg->setLayout(hlay);
  30.  
  31. 	toolbar->addWidget(widg);
  32. 	addToolBar(toolbar);
  33. }
  34.  
  35. int main(int argc, char *argv[])
  36. {
  37. 	QApplication app(argc, argv);
  38.  
  39. 	// Moving this line to the place after MainWindow creation fixes unwanted padding,
  40. 	// but may produce really weird results on Mac OS X when styling combobox drop-down area.
  41. 	app.setStyleSheet("QToolBar#mainToolbar { background: blue; border: 1px solid yellow; margin: 0px; padding 0px; } "
  42. 		" QWidget#toolbarWidget { background: green; border: 1px solid red; margin: 0px; padding: 0px; } ");
  43.  
  44.  
  45. 	MainWindow mainWindow;
  46. 	mainWindow.show();
  47.  
  48. 	return app.exec();
  49. }
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teststylesheet.png

Is there something wrong in the code or the stylesheet?

I've noticed that if I apply the stylesheet when GUI is already created, the issue disappears.

teststylesheet-correct.png

From the other side, applying stylesheet when GUI is created may produce weird results on Mac OS X, e.g. when styling combobox drop-down area. So I would like to know what is the recommended place for setting stylesheet - before or after creating GUI?