I'm making a GUI on a touchscreen (Pi). I'm using FigureCanvasTkAgg and  NavigationToolbar2Tk. The GUI seems to work but I cannot figure out how the Zoom Out function works on the touchscreen. On the PC, rectange windows drawn with left click seem to zoom in, and those drawn with right click seem to zoom out. On the Pi, I can zoom in, but not zoom out. Any assistance/pointers would be appreciated.
Apparently, there was a conflict between the event handlers. I had a event handler attached to the canvas using canvas.get_tk_widget().bind('Button-1>',self.canvas_button1_handler). When I replaced this with canvas.mpl_connect("button_press_event",fig_button_handler) the strange behaviour of zoom stopped.
matplotlib on Pi touchscreen