Rotating an object on a touch event in kivy

Question

I\'m working on making a circle that will spin kind of like a large dial. Currently, I have an arrow at the top to show which direction the dial is facing. I\'d like its b

Answer 1

You can use GearTick from garden which is a rotating slider. It's not exactly what you need but can be adapted for your needs. "By default it allows rotation anti-clockwise you probably would need it to go clockwise"(Update: The widget now has a orientation property that can be set to 'clockwise' or 'anti-clockwise').

You would need to manage the spring back and stopping at the "finger stop".

The example at the ends manage spring back using animation, however you still need to manage/implement the finger stop functionality.

https://github.com/kivy-garden/garden.geartick

Usage::

Python::

from kivy.garden.geartick import GearTick
parent.add_widget(GearTick(range=(0, 100)))

kv::

BoxLayout:
    orientation: 'vertical'
    GearTick:
        id: gear_tick
        zoom_factor: 1.1
        # uncomment the following to use non default values
        #max: 100
        #background_image: 'background.png'
        #overlay_image: 'gear.png'
        #orientation: 'anti-clockwise'
        on_release:
            Animation.stop_all(self)
            Animation(value=0).start(self)
    Label:
        size_hint: 1, None
        height: '22dp'
        color: 0, 1, 0, 1
        text: ('value: {}').format(gear_tick.value)

To install::

pip install kivy-garden
garden install geartick

Working Example that you can copy paste::

from kivy.lang import Builder
from kivy.app import runTouchApp
from kivy.garden.geartick import GearTick
runTouchApp(Builder.load_string('''
#:import Animation kivy.animation.Animation
GridLayout:
    cols: 2
    canvas.before:
        Color:
            rgba: 1, 1, 1, 1
        Rectangle:
            size: self.size
            pos: self.pos
    BoxLayout:
        orientation: 'vertical'
        GearTick:
            id: gear_tick
            zoom_factor: 1.1
            # uncomment the following to use non default values
            #max: 100
            #background_image: 'background.png'
            #overlay_image: 'gear.png'
            #orientation: 'anti-clockwise'
            on_release:
                Animation.stop_all(self)
                Animation(value=0).start(self)
        Label:
            size_hint: 1, None
            height: '22dp'
            color: 0, 1, 0, 1
            text: ('value: {}').format(gear_tick.value)
'''))