Kivy for iOS
This toolchain is designed to compile the necessary libraries for iOS to run your application and manage the creation of the Xcode project.
We do not provide any binary distributions of this toolchain. You do need to compile it at least once before creating your Xcode project.
The toolchain supports:
- iPhone Simulator (x86_64)
- iPhone / iOS (armv7 and arm64)
You can select between Python 2.7 or Python 3.7 by specifying the recipes python2 or python3 when building.
These recipes are not ported to the new toolchain yet:
Currently, the toolchain requires a few tools for compilation. You will need:
Ensure you have python3 installed - this is needed for toolchain.py:
brew install python
Ensure you have the right dependencies installed for python3:
pip3 install -r requirements.txt
Xcode 10 or above, with an iOS SDK and command line tools installed:
Using brew, you can install the following dependencies:
brew install autoconf automake libtool pkg-config brew link libtool
Install Cython (0.28.1):
# pip method if available (sudo might be needed.) pip install cython==0.28.1
Using the toolchain
Any Python extensions or C/C++ library must be compiled: you need to have what we call a recipe to compile it. For example, Python, libffi, SDL2, SDL_image, freetype... all the dependencies, compilation and packaging instructions are contained in a recipe.
You can list the available recipes and their versions with:
$ ./toolchain.py recipes audiostream master click master cymunk master distribute 0.7.3 ffmpeg 2.6.3 ffpyplayer v3.2 flask master freetype 2.5.5 hostlibffi 3.2.1 hostpython2 2.7.1 hostpython3 3.7.1 ios master itsdangerous master jinja2 master kivy 1.10.1 libffi 3.2.1 libjpeg v9a libpng 1.6.26 markupsafe master moodstocks 4.1.5 numpy 1.9.1 openssl 1.0.2k photolibrary master pil 2.8.2 plyer master pycrypto 2.6.1 pykka 1.2.1 pyobjus master python2 2.7.1 python3 3.7.1 pyyaml 3.11 sdl2 2.0.8 sdl2_image 2.0.0 sdl2_mixer 2.0.0 sdl2_ttf 2.0.12 werkzeug master
Then, start the compilation with:
$ ./toolchain.py build python3 kivy
You can build recipes at the same time by adding them as parameters:
$ ./toolchain.py build python3 openssl kivy
Recipe builds can be removed via the clean command e.g.:
$ ./toolchain.py clean openssl
The Kivy recipe depends on several others, like the sdl* and python recipes. These may in turn depend on others e.g. sdl2_ttf depends on freetype, etc. You can think of it as follows: the kivy recipe will compile everything necessary for a minimal working version of Kivy.
Don't grab a coffee, just do diner. Compiling all the libraries for the first time, 3x over (remember, 3 archs, x86_64, armv7, arm64) will take time.
For a complete list of available commands, type:
Create the Xcode project
The toolchain.py can create the initial Xcode project for you:
$ ./toolchain.py create <title> <app_directory> $ ./toolchain.py create Touchtracer ~/code/kivy/examples/demo/touchtracer
Your app directory must contain a main.py. A directory named <title>-ios will be created, with an Xcode project in it. You can open the Xcode project using:
$ open touchtracer-ios/touchtracer.xcodeproj
Then click on Play, and enjoy.
Everytime you press Play, your application directory will be synced to the <title>-ios/YourApp directory. Don't make changes in the -ios directory directly.
Configuring your App
You can configure and customize your app in various ways:
- Set the icon and launch images in XCode. Note that XCode requires that you specify these assests per device or/and iOS version.
- When you first build your XCode project, a 'main.m' file is created in your XCode project folder. This file configures your environment variables and controls your application startup. You can edit this file to customize your launch environment.
- Kivy uses SDL, and as soon as the application starts the SDL main, the launch image will disappear. To prevent that, you need to have 2 files named Default.png and Default-Landscape.png, and put them in the Resources folder in Xcode (not in your application folder)
If you wish to restrict your apps orientation, you should do this via the 'export_orientation' function in 'main.m'. The XCode orientation settings should be set to support all.
Recipes are used to install and compile any libraries you may need to use. These recipes follow the same format as those used by the Python-for-Android sister project. Please refer to the recipe documentation there for more detail.
Reducing the application size
If you would like to reduce the size of your distributed app, there are a few things you can do to achieve this:
Minimize the build/pythonX/lib/pythonXX.zip: this contains all the python modules. You can edit the zip file and remove all the files you'll not use (reduce encodings, remove xml, email...)
Go to the settings panel > build, search for "strip" options, and triple-check that they are all set to NO. Stripping does not work with Python dynamic modules and will remove needed symbols.
By default, the iOS package compiles binaries for all processor architectures, namely x86_64, armv7 and arm64 as per the guidelines from Apple. You can reduce the size of your ipa significantly by removing the x86_64 architecture as they are used only for the emulator.
The procedure is to first compile/build all the host recipes as is:
./toolchain.py build hostpython3
Then build all the rest of the recipes using --arch=armv7 --arch=arm64 arguments as follows:
./toolchain.py build python3 kivy --arch=armv7 --arch=arm64
Note that these packages will not run in the iOS emulators, so use them only for deployment.
Usage: ./toolchain.py <command> [<args>] Available commands: build Build a recipe (compile a library for the required target architecture) clean Clean the build of the specified recipe distclean Clean the build and the result recipes List all the available recipes status List all the recipes and their build status Xcode: create Create a new xcode project update Update an existing xcode project (frameworks, libraries..) launchimage Create Launch images for your xcode project icon Create Icons for your xcode project pip Install a pip dependency into the distribution
- Fatal error: "stdio.h" file not found
- You need to install the Command line tools: xcode-select --install
- You must build with bitcode disabled (Xcode setting ENABLE_BITCODE should be No).
- We don't support bitcode. You need to go to the project setting, and disable bitcode.
- You don't have permissions to run
- It is due to invalid archs, search for them and check it. Maybe you targetted a simulator but have only armv7/arm64. Maybe you want to target your iPad but it as only x86_64.
If you need assistance, you can ask for help on our mailing list:
We also have a Discord channel:
- Server : https://chat.kivy.org
- Channel : #support
We love pull requests and discussing novel ideas. Check out our contribution guide and feel free to improve Kivy for iOS.
The following mailing list and IRC channel are used exclusively for discussions about developing the Kivy framework and its sister projects:
- Server : https://chat.kivy.org
- Channel : #dev
Kivy for iOS is released under the terms of the MIT License. Please refer to the LICENSE file.