QDockWidget hide title bar - python-3.x

Question

I can't find how to hide the title bar of my Qdockwidgets :
I have found this on the references :
QDockWidget.setTitleBarWidget (self, QWidget widget)
The widget argument has it's ownership transferred to Qt.
Sets an arbitrary widget as the dock widget's title bar. If widget is 0, any custom title bar widget previously set on the dock widget is removed, but not deleted, and the default title bar will be used instead.
And this in quite a few places :
dockWidget->setTitleBarWidget(new QWidget());
but how to actually use them ? I simply can't find any simple example of code showing those in action not even in the references and all of my tries ended up with various errors.
In the whole page : http://pyqt.sourceforge.net/Docs/PyQt4/qdockwidget.html#setTitleBarWidget there is simply nothing which tell me how I can use this :
QDockWidget.setTitleBarWidget (self, QWidget widget)
If I read the documentation I should replace the "widget" one by a 0 so I get no title bar displayed
self.dockWdg1.setTitleBarWidget(self, QtGui.QWidget(0))# If I don't add QtGui in front of QWidget it don't know what is QWidget
give me this error :
TypeError: QWidget(QWidget parent=None, Qt.WindowFlags flags=0): argument 1 has unexpected type 'int'
Another question, is there actually people using this references : ? http://pyqt.sourceforge.net/Docs/PyQt4/qdockwidget.html#setTitleBarWidget
My question can seem weird but I find thoses references so incomplete (no code example) and the explanations so obscures I really wonder if I am looking on the right one, especially when on the other side we have this : http://srinikom.github.io/pyside-docs/PySide/QtGui/QDockWidget.html#PySide.QtGui.QDockWidget with pySide which seems so so so so so much better. PyQT references succeed in being even worst than MaxScript references which is not a little thing to do.
My complete code :
import sys, random
from PyQt4 import QtCore, QtGui
from PyQt4.QtGui import QPalette, QBrush, QPixmap
class MainWin(QtGui.QMainWindow):
def __init__(self):
super(MainWin, self).__init__()
self.initUI()
def initUI(self):
#central widget
self.theboard = Board(self)
self.setCentralWidget(self.theboard)
#dock1 Left Dock
self.dockWdg1 = LeftDock(self)
#Use SizeQWidget() to define the initial size of QDockWidget
self.content1 = SizeQWidget()
self.dockWdg1.setWidget(self.content1)
self.dockWdg1.setFeatures(self.dockWdg1.NoDockWidgetFeatures)
self.addDockWidget(QtCore.Qt.LeftDockWidgetArea, self.dockWdg1)
self.dockWdg1.setTitleBarWidget(self, QtGui.QWidget(0))# If I don't add QtGui in front of QWidget it don't know what is QWidget
self.resize(360, 760)
self.setWindowTitle('Test')
self.show()
class LeftDock(QtGui.QDockWidget):
def __init__(self, parent):
super(LeftDock, self).__init__(parent)
self.initLeftDock()
def initLeftDock(self):
self.setGeometry(300, 300, 200, 120)
#self.setWindowTitle('LeftDock')
class Board(QtGui.QFrame):
def __init__(self, parent):
super(Board, self).__init__(parent)
self.initBoard()
def initBoard(self):
print("ddd")
#Dummy QWidget used by QDockWidget for defining initial size.
class SizeQWidget(QtGui.QWidget):
def sizeHint(self):
return QtCore.QSize(100, 75)
def main():
app = QtGui.QApplication([])
mw = MainWin()
sys.exit(app.exec_())
if __name__ == '__main__':
main()

Answer 1

The PyQt docs are automatically created from the C++ docs. I always just use the C++ docs.
The docs are thus not of very good overall quality.
Now to your main issue at hand.
Note that QtGui.QWidget takes a QObject* as first parameter (the parent of the newly created object). Also note that a null pointer is represented in Python by None, not 0.
Then we need to know that self is usually implicitly passed by calling the method on an instance. (self in the context of PyQt is just like every other self you will ever encounter in Python).
Thus, this works:
self.dockWdg1.setTitleBarWidget(QtGui.QWidget(None))
Personally I would do this a little bit different:
self.dockWdg1.setTitleBarWidget(QtGui.QWidget(self.dockWdg1))
That is, setting the parent of the title bar widget to the dock widget itself, preserving a nice object hierarchy.
I might also remark that "removing" the title bar widget of a dock widget by replacing it with an invisible (size is zero) widget it becomes impossible to float the dock widget.

Answer 2

i use this to hide them all in c++
for (auto &dock:findChildren<QDockWidget*>())
dock->setTitleBarWidget(new QWidget);