Simple implementation of a hold behavior for buttons.

test_hold.py

'''
'''
from kivy.app import App
from kivy.lang import Builder
from kivy.factory import Factory
from kivy.clock import Clock
from kivy.properties import NumericProperty


KV = '''
<HoldButton@HoldBehavior+Button>:


FloatLayout:
    HoldButton:
        text: 'test'
        on_press: print("press")
        on_hold: print("hold")
        on_release: print("release")
'''

class Application(App):
    def build(self):
        return Builder.load_string(KV)

class HoldBehavior:
    __events__ = ['on_hold']
    timeout = NumericProperty(1)

    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self._event = None

    def _cancel(self):
        if self._event:
            self._event.cancel()

    def on_press(self):
        self._cancel()
        self._event = Clock.schedule_once(lambda *x: self.dispatch('on_hold'), self.timeout)
        return super().on_press()

    def on_hold(self, *args):
        pass

    def on_release(self):
        self._cancel()

Factory.register('HoldBehavior', cls=HoldBehavior)

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

Thanks for this snippet, very useful 👍

I made HoldBehavior inherit from ButtonBehavior in order for this to work on widgets that don't implement the on_press() and on_release() methods:

from kivy.uix.behaviors import ButtonBehavior


class HoldBehavior(ButtonBehavior):
    __events__ = ['on_hold']
    timeout = NumericProperty(1)

    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self._event = None

    def _cancel(self):
        if self._event:
            self._event.cancel()

    def on_press(self):
        self._cancel()
        self._event = Clock.schedule_once(lambda *x: self.dispatch('on_hold'), self.timeout)
        return super().on_press()

    def on_hold(self, *args):
        pass

    def on_release(self):
        self._cancel()


Factory.register('HoldBehavior', cls=HoldBehavior)