Using QGIS in an External Application - Building Mapping Applications with QGIS - page 147

Connecting the actions
You might have noticed that none of the menu commands and toolbar icons do anything
yet—even the Quit command doesn't work. Before our actions do anything, we have to
connect them to the appropriate method. To do this, add the following to your MapEx-
plorer.__init__() method, immediately after the call to setupUi() :
self.connect(self.actionQuit,
SIGNAL("triggered()"), qApp.quit)
self.connect(self.actionShowBasemapLayer,
SIGNAL("triggered()"),
self.showBasemapLayer)
self.connect(self.actionShowLandmarkLayer,
SIGNAL("triggered()"),
self.showLandmarkLayer)
self.connect(self.actionZoomIn,
SIGNAL("triggered()"), self.zoomIn)
self.connect(self.actionZoomOut,
SIGNAL("triggered()"), self.zoomOut)
self.connect(self.actionPan,
SIGNAL("triggered()"), self.setPanMode)
self.connect(self.actionExplore,
SIGNAL("triggered()"),
self.setExploreMode)
We're connecting our Quit action to the qApp.quit() method. For the other actions,
we'll be calling methods within our MapExplorer class itself. Let's define some place-
holders for these methods:
def showBasemapLayer(self):
pass
def showLandmarkLayer(self):
pass
def zoomIn(self):
pass