An example of using gestures4kivy
2023-11-13 This repository is archived.
This example depends on the gestures4kivy package, which must be installed. The package install, API, and any known hardware specific issues are documented on the package homepage.
Run the example main.py it has five screens. It may be run on any OS.
The first screen demonstrates a Screen that responds to a swipe. To implement we create a new class SwipeScreen inheriting from Screen. A callback is added for each gesture we choose to recognize:
### A swipe sensitive Screen
class SwipeScreen(Screen, CommonGestures):
def cgb_horizontal_page(self, touch, right):
# here we add the user defined behavior for the gesture
# this method controls the ScreenManager in response to a swipe
App.get_running_app().swipe_screen(right)
In this case the swipe_screen() method implements the gesture behavior when the callback occurs. The SwipeScreen class is added to the screen manager in the usual way. And swipe_screen() controls the screen manager as shown in main.py.
The GestureCanvas example illustrates changing objects on a canvas, the long press move gesture, and the utility of visual feedback with a long press. See the full example gesturecanvas.py.
Another example is ZoomImage an Image widget that pans, and zooms from the texture to optimize for resolution. See the full example zoomimage.py.
Some Kivy widgets have gestures predefined. You can replace the gestures by making a copy of CommonGestures and replacing its inheritance from Widget with inheritance from the Kivy widget you want to modify. Then implement the calls to that widget's behavior.
The Android Back Gesture is not included in CommonGestures as its use is now limited because on Android >= 10 devices the back gesture is used to pause an app. However an example usage is shown in main.py.