binding.py

from kivy.uix.boxlayout import BoxLayout
from kivy.app import App
from kivy.uix.button import Button
from functools import partial

class DemoBox(BoxLayout):

    def __init__(self, **kwargs):
        super(DemoBox, self).__init__(**kwargs)
        self.orientation = "vertical"

        btn = Button(text="Normal binding to event")
        btn.fbind('on_press', self.on_event)

        btn2 = Button(text="Normal binding to a property change")
        btn2.fbind('state', self.on_property)

        btn3 = Button(text="A: Using function with args.")
        btn3.fbind('on_press', self.on_event_with_args, 'right',
                       tree='birch', food='apple')

        btn4 = Button(text="Unbind A.")
        btn4.fbind('on_press', self.unbind_a, btn3)

        btn5 = Button(text="Use a flexible function")
        btn5.fbind('on_press', self.on_anything)

        btn6 = Button(text="B: Using flexible functions with args. For hardcores.")
        btn6.fbind('on_press', self.on_anything, "1", "2", monthy="python")

        btn7 = Button(text="Force dispatch B with different params")
        btn7.fbind('on_press', btn6.dispatch, 'on_press', 6, 7, monthy="other python")

        btn8 = Button(text="bind A")
        btn8.fbind('on_press', self.bind_a, self.on_event_with_args ,btn3)

        for but in [btn, btn2, btn3, btn4, btn5, btn6, btn7, btn8]:
            self.add_widget(but)

    def on_event(self, obj):
        print("Typical event from", obj)

    def on_event_with_args(self, side, obj, tree=None, food=None):
        print("Event with args", obj, side, tree, food)

    def on_property(self, obj, value):
        print("Typical property change from", obj, "to", value)

    def on_anything(self, *args, **kwargs):
        print('The flexible function has *args of', str(args),
            "and **kwargs of", str(kwargs))
        return True

    def unbind_a(self, btn, event):
        btn.funbind('on_press', self.on_event_with_args, 'right',
                        tree='birch', food='apple')
        print("unbound")
    def bind_a(self, obj, btn, event):
    	btn.fbind('on_press', event, 'right',
                       tree='birch', food='apple')
    	print("bound")


class DemoApp(App):
    def build(self):
        return DemoBox()

if __name__ == "__main__":
    DemoApp().run()

Have this traceback after 'Bind A'-'Unbind A' or 'A'-'Bind A'-'A'
Is this ok?

   File "main.py", line 69, in <module>
     DemoApp().run()
   File "/usr/lib/python3/dist-packages/kivy/app.py", line 855, in run
     runTouchApp()
   File "/usr/lib/python3/dist-packages/kivy/base.py", line 502, in runTouchApp
     EventLoop.window.mainloop()
   File "/usr/lib/python3/dist-packages/kivy/core/window/window_sdl2.py", line 724, in mainloop
     self._mainloop()
   File "/usr/lib/python3/dist-packages/kivy/core/window/window_sdl2.py", line 459, in _mainloop
     EventLoop.idle()
   File "/usr/lib/python3/dist-packages/kivy/base.py", line 340, in idle
     self.dispatch_input()
   File "/usr/lib/python3/dist-packages/kivy/base.py", line 325, in dispatch_input
     post_dispatch_input(*pop(0))
   File "/usr/lib/python3/dist-packages/kivy/base.py", line 231, in post_dispatch_input
     listener.dispatch('on_motion', etype, me)
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib/python3/dist-packages/kivy/core/window/__init__.py", line 1360, in on_motion
     self.dispatch('on_touch_down', me)
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib/python3/dist-packages/kivy/core/window/__init__.py", line 1376, in on_touch_down
     if w.dispatch('on_touch_down', touch):
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib/python3/dist-packages/kivy/uix/widget.py", line 460, in on_touch_down
     if child.dispatch('on_touch_down', touch):
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib/python3/dist-packages/kivy/uix/behaviors/button.py", line 151, in on_touch_down
     self.dispatch('on_press')
   File "kivy/_event.pyx", line 703, in kivy._event.EventDispatcher.dispatch
   File "kivy/_event.pyx", line 1214, in kivy._event.EventObservers.dispatch
   File "kivy/_event.pyx", line 1088, in kivy._event.EventObservers._dispatch
 TypeError: 'Button' object is not callable