Developing apps with Kivy
- 1. Pycon 2016 Developing Apps for Android and Other Platforms with Kivy and Python Pushpendra Tiwari
- 2. Outline Introduction Python Kivy Limitations Credits
- 3. Python
- 4. Python General-purpose, high-level programming language Object-oriented, aspect-oriented, functional Dynamic type system Easy-to-learn with clear and expressive syntax def faculty(x): if x > 1: return x * faculty(x - 1) else: return 1
- 5. Python on Mobile Devices Early Mobile Development with Python PyS60 for Symbian Python CE for Windows Mobile Current Mobile Development with Python • Scripting Layer for Android (SL4A) • Python for Android (Py4A) • PySide / Qt for Android • WinRT / IronPython for Windows 8 • Kivy…
- 6. Kivy
- 7. Kivy Platform-independent Python- Framework Available for Android iOS Meego Windows Linux OSX (Raspberry Pi) Development in Python on all platforms Not emulated! kivy.org
- 8. Kivy Basics Framework for Natural User Interfaces (NUI) Touchscreens / Multi-Touch GPU accelerated graphics • Based on OpenGL ES 2.0 Suitable for prototypes as well as products • Porting to new platforms is easy
- 9. Kivy Software Open Source (LGPL), 7 Core developer • Source code: https://github.com/kivy • Documentation: http://kivy.org/docs • Kivy on Google Play: https://play.google.com/store/apps/details?id=org.kivy.pygame
- 10. Kivy says Hello! from kivy.app import App from kivy.uix.button import Button class HelloApp(App): def build(self): return Button(text='Hello Berlin') HelloApp().run()
- 12. Development with Kivy Python for widgets, input, program logic • Language KV for layout und graphics • Cython for low-level access to graphic routines
- 13. “Hello Berlin” with KV from kivy.app import App class HelloApp(App): pass HelloApp().run() #:kivy 1.0 Button: text: ‘Hello Berlin’ File hello.kv defines root widget
- 14. Example: Pong import kivy from kivy.app import App from kivy.uix.widget import Widget class PongGame(Widget): pass class PongApp(App): def build(self): return PongGame() if name == ' main ': PongApp().run()
- 15. Pong Graphics #:kivy 1.6.0 <PongGame>: canvas: Rectangle: pos: self.center_x - 5, 0 size: 10, self.height Label: font_size: 70 center_x: root.width / 4 top: root.top - 50 text: "0" Label: font_size: 70 center_x: root.width * 3 / 4 top: root.top - 50 text: "0"
- 17. Accessing Java Classes from Python Smartphones have many APIs Camera, Compass, Contacts, Location, … Access from Python via PyJNIus • https://github.com/kivy/pyjnius • Implemented with JNI and Java reflection Example from jnius import autoclass Hardware = autoclass('org.renpy.android.Hardware') print 'DPI is', Hardware.getDPI()
- 18. Packaging Creating packages for Windows, OSX, Android und iOS: http://kivy.org/docs/guide/packaging.html
- 19. Build Tools Tool chain Python-for-android Cross compiler for ARM Android SDK & NDK Python and some Python packages Buildozer • Hides the complexity: Downloads, compiles, packages Kivy source code • https://github.com/kivy/buildozer % buildozer android debug deploy run
- 20. Kivy Showcase
- 21. Limitations
- 22. Missing, but Planned (or In Progress) User Interface Designer Design tool for Kivy Language KV Abstraction of mobile APIs • Platform-independent Python wrapper for platform APIs (Android, iOS, Linux/Mac/Windows) Porting to Raspberry Pi • Useful for small/cheap standalone systems
- 23. Credits Thanks to the Kivy developers Mathieu Virbel (@mathieuvirbel) • Thomas Hansen (@hansent) • Gabriel Pettier (@tshirtman) • and many others
- 24. Questions? Summary Kivy allows platform-independent development of apps for Android, iOS, Meego, Windows, OSX and Linux Suitable for multi-touch and graphics applications, such as kiosk systems, exhibits, games, …er Twitter: