QtFirebase C++ Demo

A simple implementation of Firebase C++ SDK for Qt 5

Download and unzip the Firebase C++ SDK into firebase_cpp_sdk folder at the project roor (or wherever you want it, but take note of the path), this project was tested with version 3.1.0 of the C++ SDK

How it Works

QObject wrappers where created extending QObject and a corresponding class for each Firebase module (Messaging only for now), a singleton was used in each class to keep track of the static references required, in particular to the firebase::App

The first time a FirebaseMessaging is instantiated in QML a singleton is assigned and set as the listener for the OnMessage and OnTokenReceived, following object instances are connected to this singleton signals to propagate, a topic filter is implemented allowing a particular instance of this class to emit messages for specific topics.

Create a FirebaseAppobject, not required but useful to check if the app is ready.

import Firebase 1.0

...

FirebaseApp{
    id: firebaseApp
    Component.onCompleted: {
        console.log("FirebaseApp "+ready)
    }
}

Instantiate anywhere a FirebaseMessaging object and call subscribe(<topic_name>) on the onCompleted, if the topicFilter property is set only messages for those topics are received here, if not it will receive all messages.

FirebaseMessaging{
    topicFilter: ["your_topic"]
    onFcmTokenChanged: {
        console.log("FCM Token " + fcmToken);
    }
    Component.onCompleted: {
      subscribe("your_topic");
    }
}

Android

Go to the project settings in Qt and create a template for the Android app, this will create gradle specific files and ask you to overwrite the AndroidManifest.xml (go ahead if you want a different config), add the corresponding lines in the gradle.properties and local.properties as described in the Firebase Docs

gradle.properties

systemProp.firebase_cpp_sdk.dir=~/your_local_firebase_sdk_dir

local.properties

ndk.dir=~/your_local_ndk_dir

This last step is probably managed by Qt Creator

Please note that a reference to the library is located at the .pro file:

android{...

LIBS += -L$$PWD/firebase_cpp_sdk/libs/android/armeabi-v7a/gnustl/ -lmessaging -ldatabase -lauth -lapp \

INCLUDEPATH  += $$PWD/firebase_cpp_sdk/include
DEPENDPATH += $$PWD/firebase_cpp_sdk/libs/android/armeabi-v7a/gnustl/
}

-lapp must be the last library linked otherwise you will get a linker error.

The Google Firebase dependencies are set in the build.gradle file:

build.gradle

repositories {
  flatDir {
    dirs System.getProperty('firebase_cpp_sdk.dir') + "/libs/android"
  }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.google.firebase:firebase-core:10.2.4'
    compile 'com.google.firebase:firebase-messaging:10.2.4'
    compile 'com.google.firebase:firebase-analytics:10.2.4'
    compile 'com.google.firebase:firebase-database:10.2.4'
    compile 'com.google.firebase:firebase-crash:10.2.4'
    compile 'com.google.firebase:firebase-auth:10.2.4'
    compile 'com.google.firebase.messaging.cpp:firebase_messaging_cpp@aar'
    compile 'com.google.android.gms:play-services-base:10.2.4'
}

apply plugin: 'com.google.gms.google-services'

Set your package name in the same file:

  defaultConfig {
      applicationId "org.qtproject.firebasedemo"
  }

At this point Qt should build the application but gradle can complain about a version so set it to gradle-2.14.1-all.zip at the gradle-wrapper.properties file.

Remember to generate your google-services.json file and place it in the android folder

iOS