explicitly setting style sheet in python pyqt4?
Question: In pyqt standard way for setting style sheet is like this  
  
`MainWindow.setStyleSheet(_fromUtf8("/*\n" "gridline-color: rgb(85, 170,
255);\n" "QToolTip\n" "{\n" " border: 1px solid #76797C;\n" " background-
color: rgb(90, 102, 117);;\n" " color: white;\n" " padding: 5px;\n" " opacity:
200;\n" "}\n" "#label_3{\n" " background-color:rgb(90, 102, 117);\n" "
color:white;\n" " padding-left:20px;\n" " \n" "}\n" "#label_2{\n" "
color:white;\n" " padding-left:20px;\n" " \n" "}\n"`

But like we link the stylesheet in html `<link rel="stylesheet"
href="style.css">` .can't we do the same in pyqt?It helps in organizing the
things.


Answer: There are currently only two main ways to set a stylesheet. The first is to
use the `setStyleSheet` method:

    
    
    widget.setStyleSheet("""
        QToolTip {
            border: 1px solid #76797C;
            background-color: rgb(90, 102, 117);
            color: white;
            padding: 5px;
            opacity: 200;
        }
        """)
    

This will only take a string, so an external resource would need to be
explicitly read from a file, or imported from a module.

The second method is to use the [`-stylesheet` command-line
argument](http://doc.qt.io/qt-4.8/qapplication.html#QApplication), which
allows an external qss resource to be specified as a path:

    
    
    python myapp.py -stylesheet style.qss
    

This opens up the possibility of a tempting hack, since it is easy enough to
manipulate the args passed to the `QApplication` constructor, and explicitly
insert a default stylesheet:

    
    
    import sys
    
    args = list(sys.argv)
    args[1:1] = ['-stylesheet', 'style.qss']
    
    app = QtGui.QApplication(args)
    

(Inserting the extra arguments at the beginning of the list ensures that it is
still possible for the user to override the default with their own
stylesheet).

