QtRpi

Purpose

Offer an easy-to-use environment to cross-compile Qt application on a Raspberry Pi. This repo contains all the scripts needed to prepare a sysroot, cross-compile Qt and deploy Qt libraries to your Raspberry.

For more information, go to the wiki

Difference between init-qtrpi-minimal and init-qtrpi-full

• init-qtrpi-minimal, the typical way: downloads ready-to-use Qt binaries for the Raspberry Pi and a minimal sysroot that we released on the download page
• init-qtrpi-full, the custom way: compiles on your computer the Qt binaries for the Raspberry Pi to let you tweak the configuration, enhance the compilation by adding some missing Qt modules to QtRpi or add some specific third-party dependencies

Summary

	init-qtrpi-minimal	init-qtrpi-full
Raspbian image		from raspberrypi.org
Toochain	from the github project	from the github project
Sysroot	from qtrpi team	generated from raspbian image
Qt binaries	from qtrpi team	compiled

Tutorial of init-qtrpi-minimal.sh

This tutorial will help you to:

• Configure your host computer to be able to cross-compile Qt 5.7.0 applications for your Raspberry Pi 3
• Deploy the pre-compiled Qt binaries on your Raspberry Pi
• Cross-compile your application for a Raspberry Pi with the CLI or Qt Creator

Requirements

• A 64-bit Linux host computer
• A Raspberry Pi 3 with Raspbian Jessie (Raspbian Stretch is currently not supported!)

In this example, you already have an SSH access to your Raspberry Pi 3 at 192.168.1.12 with the user pi. The script will use sudo several times to install the packages on the board. You should add your SSH key in your Raspberry Pi. For example with ssh-copy-id:

ssh-copy-id [email protected]

Installation

First, install the dependencies:

sudo apt-get install curl g++ gdb-multiarch git realpath unzip zip

Open a terminal and follow the steps below:

git clone https://github.com/neuronalmotion/qtrpi.git
cd qtrpi
export QTRPI_QT_VERSION='5.7.0'
export QTRPI_TARGET_DEVICE='linux-rpi3-g++'
export QTRPI_TARGET_HOST='[email protected]'
./init-qtrpi-minimal.sh
./deploy-qtrpi.sh --prepare-rpi

Note: You can also export the environment variables in your .bashrc.

Usage in CLI

cd myproject
/opt/qtrpi/bin/qmake-qtrpi
make

You can now copy and execute the generated binary file on your Raspberry Pi

Note: You can also add /opt/qtrpi/bin/ to your PATH in your .bashrc and call qmake-qtrpi without the full path.

Usage in Qt Creator

How to build a Raspberry Pi 3 application from your desktop Qt Creator (step by step video):

Tutorial of init-qtrpi-full.sh

How to add a new Qt module in QtRpi?

• In this case, you must use init-qtrpi-full.sh, because you will have to recompile it on your computer
• All the modules are cloned from the official Qt website (http://code.qt.io/)
• If you want to add a module, just add the repository name in the file qt-modules.txt
• You might have to add some packages in the sysroot, this can be done in utils/prepare-sysroot-full.sh
• Once you have modified these scripts, you should be able to re-execute init-qtrpi-full.sh and see the magic happen.

Docker images

The images are tagged according to their target configuration.

Currently the following tags are available:

• rpi3-qt5.6.2: Crosscompile Qt 5.6.2 for the Raspbarry Pi 3

Choose the image which fits your needs.

Building a Qt project

To build a Qt project, mount the directory containing the sources and the project file to the /sources path inside the container and run it. By default the image automatically executes qmake and make in the current working directory, which is set to /sources by default.

Example

docker pull arose/qtrpi:rpi3-qt5.6.2
docker run -v /someqtprojectfolder/:/source arose/qtrpi:rpi3-qt5.6.2