wiki:android

Porting modRana to Android

As there is currently no GTK port for Android and not even any project trying to do this, only the QML GUI is relevant for running modRana on Android.

Most of this is based on THP's excellent ''PySide for Android'' work.

Notes from THP's EuroPython 2012 talk

NOTE: This article describes the modRana, Mieru & co porting process for Android. For generic instructions how to build, deploy & use PySide on android, see the PySide for Android article.

For (work-in-progress) information about how to use and deploy PyOtherSide on Android, see the PyOtherSide for Android article.

Prerequisites

Python

Python is needed as modRana is written in Python. The the binary Python 2.7 distribution provided by the android-python27 project can be used. This archive also contains the PyQt binaries.

To be usable, the lib directory needs to be added to LD_LIBRARY_PATH, the corresponding Python directories to PYTHONPATH and bin added to PATH. The main python binary might also need to be set executable.

NOTE: You can't launch graphical applications directly on Android as on Desktop or on Maemo. The application needs a launcher that properly loads the Qt libraries and sets-up the enveloping activity.

Building Python for Android (android-python27)

The Android-python27 project achieved not only to build Python for Android, generate custom APKs but also to build PyQt compatible with their build & Qt libraries provided by the Necessitas project.

README
README - build with PyQt

Python from the Kivi project

There is another actively maintaned Python distribution for Android, provided by the Kivi project. It seems to work as well as android-python27, but I had issues building it on my Ubuntu 12.10 & NDK r8 machine. Built just fine on 12.04 @ NDK r7. There is also a virtual machine for even easier building

See the Kivy Python for Android article for build instructions.

Building SIP

error: cannot find -lsupc++

Probably cause - the source contains makefiles built against an old NDK version.

I've not yet been able to rebuild PyQt? for Android from source. The compiled binaries from the android-python27 project work fine though.

Qt + QML

The Necessitas project provides Qt libriries with QML support. Due to Android lacking proper package management, there is an android application called Ministro that handles library installation requests from applications using Necessitas.

When an application using Necessitas is started for the first time, it redirects the user to the Google Play store to install Ministro. Once Ministro is installed and its service is running, the application calls this service to request the Qt Libraries it needs.

If the libraries are updated or the application needs more libraries, the Ministro service handles everything automatically.

It seems that content of this request is governed by the libs.xml file in the Necessitas application package - if some libs are missing, this file needs to be modified. Alternativelly, this can be easily from the the Necessitas Qt Creator.

There are two Ministro versions:

  • Ministro - provides Alpha 2 (0.2) libraries <- OBSOLETE
  • Ministro II - provides Alpha 3 libraries (cca 0.34)

The Alpha 2 Qt libraries provided by necessitas are outdated and have many issues, such as:

  • text both in Qt widgets and QML is rendered as rectangles unless it is set to italic

So use Alpha 3+ libries if possible. This unfortunately means that the precompiled PySide? libraries provided by THP will no longer work - use the PyQt libraries from the android-python27 project instead.

This is more of a technical overview as from the point of view of the Python application, all this (making sure Ministro is installed & requesting Qt Libraries) is handled by the PySide Launcher and the application does'n need to be even aware of it.

PySide

To work, PySide binaries need to be compatible with the installed Python & Qt versions.

Compiled PySide binaries are part of the Python tarball provided by THP.

PySide Launcher

PySide programs can't be currently launched from the shell and have to use a special launcher application that makes sure all needed libraires are avalable and provides the application with acces to the screen.

There is a PySide Launcher APK on THPs site, but it doesn't work with QtDeclarative due to missing dependency on libQtOpenGL.

As a result, the PySide launcher source needs to be slightly modified and a new APK created.

Modified Pyside Launcher

Software prerequisites:

  • ant
  • Necessitas Qt SDK
Modifying the PySide Launcher project

get the source from Gtihub:

git clone https://github.com/thp/pyside-launcher-android.git

Then in in: pyside-launcher-android/android/res/values/libs.xml

The qt_libs section should look like this:

    <array name="qt_libs">
        <item>QtCore</item>
        <item>QtGui</item>
        <item>QtDeclarative</item>
        <item>QtOpenGL</item>
    </array>

This file is used to request Qt libraries from Ministro - if you need more libraries, add them there. Don't forget to omit the lib prefix.

List of libraries available from Ministro (Alpha 2):

http://files.kde.org/necessitas/qt/android/armeabi-v7a/objects/0.21/lib/

Rebuilding the APK

First, change in pyside-launcher/android/local.properties path to the sdk.dir to poin to the Android SDK inside the Necessitas SDK, for example:

sdk.dir=/home/user/necessitas/android-sdk

Then run ant like this inside the android folder

cd pyside-launcher/android
and debug

(adb complains about the package created by ant release due to missing certificates, but likes the package created by ant debug just fine)

If ant complains about outdated project, update the project using the android tool, which is normally available in the tools directory in the Android-sdk.

android update project -p pyside-launcher/android/

Qt Components

There are at least three Android ports of Qt Components.

The modified Ineans Qt Components:
https://qt.gitorious.org/~martink/qt-components/martinks-ineans-qt-components/commits/android

The koyinings one based on the Symbian Qt Components:
https://gitorious.org/~koying/qt-components/android-qt-components

And the one that is based on MeeGo Qt Components by Filip Brcic:
https://qt.gitorious.org/~brcha/qt-components/qt-components-android

I've been able to successfully compile both component sets. As my applications are using the MeeGo based components on Fremantle & Harmattan, I'll start with those.

Compiling Qt Components with necessitas

The modified Inens Qt components are based on both the Inneans Fremantle component port & Martin Kolmans changes for BB10 support. These components use the familiar Fremantle & Harmattan import syntax:

import com.nokia.meego 1.0

So it is possible to reuse code from Fremantle & Harmattan (and BB10 project using these components) without having to rewrite the import statement.

First clone the components and then switch to the android branch:

git clone git://gitorious.org/~martink/qt-components/martinks-ineans-qt-components.git
cd qt-components-android
checkout android

The export path to the Necessitas Qt libraries to compile against:

export QTDIR=<path to the Necessitas SDK>/Android/Qt/482/armeabi
export PATH="$QTDIR/bin:$PATH"

NOTE: Check out the Qt version in your Necessitas SDK version, it might not be exactly 482 (Qt 4.8.2) but older or newer.

Then configure the components for building:

./configure -fremantle -no-maliit -make cssu -force-local-theme -mobility -no-xrandr -no-xdamage -nomake examples

And build them:

make -j 5

Once the build is finished, the results are available in the imports folder. Just move it somewhere to your Android device or inside your application package and set the QML_IMPORT_PATH environmental variable to point where the folder is located.

Modifineg the components For some reason, the source code is present in multiple copies (probably because of of how the SSU/CSSU versions were patched from the upstream Qt Components ?). Anyway, if want your modifications to the source code to take effect once reconfigured & recompiled, edit the files in src/fremantle/cssu/. Modifing the others has no effect on the components that are actually built using the configure options described above.

Compiling Brchas Qt Components with Necessitas

Clone the android Qt Components Git repository and make sure you are on the android branch:

git clone git://gitorious.org/~brcha/qt-components/qt-components-android.git
cd qt-components-android
checkout android-master-stable

Then add the Necessitas Qt libraries & the Necessitas NDK to your PATH:

export ANDROID_NDK_ROOT=<path to folder with the Necessitas SDK>/necessitas/android-ndk
export ANDROID_TARGET_ARCH=armeabi
export QTDIR=<path to folder with the Necessitas SDK>/necessitas/Android/Qt/482/armeabi
export PATH="$QTDIR/bin:$PATH"

Setting the ANDROID_TARGET_ARCH is optional, it can be set either to armeabi or to armeabiv7 for some improved (?) ABI with floating point acceleration (?).

And configure the Qt components against them.

./configure --android

Then just run make (using -j is fine):

make -j6

After the compilation finishes, the results are inside the imports folder.

Compiling the other Qt Components with Necessitas

Compiling the Symbian-based Qt Components (from ~koying) is very similar to the MeeGo? based components.

git clone git://gitorious.org/~koying/qt-components/android-qt-components.git
cd android-qt-components
checkout 1.1-android

The environmental variables for the build are the same:

export ANDROID_NDK_ROOT=<path to folder with the Necessitas SDK>/necessitas/android-ndk
export ANDROID_TARGET_ARCH=armeabi
export QTDIR=<path to folder with the Necessitas SDK>/necessitas/Android/Qt/482/armeabi
export PATH="$QTDIR/bin:$PATH"

The configuration step is a bit different. QtMobility? needs to be disabled or else the build will fail & there is no --android

./configure -no-mobility

Then:

make -j6

Results are again in in the imports folder. Even the importa statement is the same:

import com.nokia.android 1.1

Qt Components Theme

Qt Components need a theme to work correctly. Without a theme, not only would most elements be transparent but also the layout is quite broken.

There are multiple sources for a working theme:

  • taking it from the Qt SDK
  • from an N9 filesystem
  • from the Fremantle Qt Components theme package
  • from Nemo

Building optional dependencies

Libmagic

Libmagic is not needed by modRana, but is required by Mieru and other ports to Android might also find it useful.

First, get the actual sources for the File command (5.11 at the time of writing).

Next, you need to replace the host definition files by newer ones, that known the linux-arm-androidabi host, in the file-5.11 folder:

rm config.sub
rm config.guess
wget http://gcc.gnu.org/svn/gcc/branches/cilkplus/config.sub
wget http://gcc.gnu.org/svn/gcc/branches/cilkplus/config.guess

Then configure and compile (don't forgett to replace all the <> quoted paths with valid ones):

# based on: http://mdqinc.com/blog/2011/09/cross-compiling-python-for-android/
export ANDROID_NDK=<path to>/android-ndk
export PATH="$ANDROID_NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/:$ANDROID_NDK:$ANDROID_NDK/tools:/usr/local/bin:/usr/bin:/bin"
export ARCH="armeabi"
export CFLAGS="-DANDROID -mandroid -fomit-frame-pointer --sysroot $ANDROID_NDK/platforms/android-14/arch-arm"
export CXXFLAGS = "$CFLAGS"
export CC="arm-linux-androideabi-gcc $CFLAGS"
export CXX="arm-linux-androideabi-g++ $CXXFLAGS"
export AR="arm-linux-androideabi-ar"
export RANLIB="arm-linux-androideabi-ranlib"
export STRIP="arm-linux-androideabi-strip --strip-unneeded"

cd file-5.11

make clean

./configure --prefix=<path to some folder>/out --host=arm-linux-androideabi --build=amd64-pc-linux-gnu --disable-static

read -p "Press any key to continue... " -n1 -s

make -j5
make install

The result will be in the out folder, specified by the results path. Just pack them with you application and set the corresponding environmental variables accordingly. :)

TODO: Add an archive with the binaries once the library is found to actually work. :)

Updated Prerequisites

While the above mentioned combination works, it could be improved by using more up to date software packages.

Python

As modRana and Mieru run just fine with Python 2.5, Python version is really not a limiting factor. Any Python version that compiles on Android and is compatible with other prerequisites will do.

Qt + QML

The currently used Necessitas Qt version (0.2 -> Alpha 2) is outdated and causes quite a few issues - most being, that all text is rendered as rectangles, unless it is set to be itallic.

As a result, it should be a priority to start using the Necessitas Alpha 3 (0.34+-) as soon as possible.

To do this, the following is needed:

  • a Python distribution compiled for Android
  • compiling PySide against this Python version & the Necessitas Qt
  • an updated PySide Launcher that uses Ministro II (which provides the Alpha 3 libraries)

PySide

At least version 1.0.5 should be used, as this is the version that is running Fremantle CSSU, without any issues. Some older version on vanilla PR 1.3 Fremantle is known to cause issues, namely with multiple decorators for a single method.

Qt Components

FAQ

error: insufficient permissions for device

First do:

adb stop-server

Then as root do:

adb start-server

Show live log from Android

adb shell
logcat

Take screenshot

Since Android 4, this very simple & easy method can be used:

adb shell /system/bin/screencap -p /sdcard/screenshot.png
adb pull /sdcard/screenshot.png screenshot-$(date +%Y%m%d%H%M%S).png

The resulting screenshot is saved in the current directory with a timestamp, so these commands can be run multiple times without overwriting the resulting file.

Necessitas import and plugin paths (Ministro I.)

/data/data/eu.licentia.necessitas.ministro/files/qt/imports
/data/data/eu.licentia.necessitas.ministro/files/qt/plugin
Last modified 5 years ago Last modified on May 24, 2014 10:39:41 PM