Why won't QToolTips appear on QActions within a QMenu

I'm doing an app with in GUI written with PySide. I set a QMenu on a QPushButton, added several QActions via QMenu.addAction. To further explain these actions to the user I added QToolTip's to these with QAction.setToolTip.

When I run the GUI now my QToolTip won't show. The example posted below reproduces the same issue, any ideas?

Thanks in advance

import sys
from PySide import QtGui

class Example(QtGui.QPushButton):

    def __init__(self, parent = None):
        super(Example, self).__init__(parent)

        self.setText('TestMenu')
        self.setToolTip('This is a Test Button')

        menu = QtGui.QMenu(self)
        action_1 = menu.addAction('Action1')
        action_1.setToolTip('This is action 1')
        action_2 = menu.addAction('Action2')
        action_2.setToolTip('This is action 2')
        action_3 = menu.addAction('Action3')
        action_3.setToolTip('This is action 3')
        action_4 = menu.addAction('Action4')
        action_4.setToolTip('This is action 4')

        self.setMenu(menu)
        self.show()

def main():
    app = QtGui.QApplication(sys.argv)
    ex = Example()

    app.exec_()

if __name__ == '__main__':
    main()

Solution

In Qt-5.1 or later, you can simply use QMenu.setToolTipsVisible, and the menu items will show their tooltips as expected (see QTBUG-13663):

    menu.setToolTipsVisible(True)

However, for Qt-4.* and Qt-5.0, the situation is different. If an action is added to a toolbar, its tooltip will be shown; but if the same action is added to a QMenu, it won't be, and there is no built-in API to change that. There are a couple of ways to work around this. One is to use status tips instead, which will show the menu-item information in the status-bar. The other is to implement the menu-item tooltip functionality yourself using the QMenu.hovered signal and QToolTip.showText:

        self.menu = QtGui.QMenu(self)
        ...
        self.menu.hovered.connect(self.handleMenuHovered)

    def handleMenuHovered(self, action):
        QtGui.QToolTip.showText(
            QtGui.QCursor.pos(), action.toolTip(),
            self.menu, self.menu.actionGeometry(action))