Get Started for Android

Your first Android App with Chat21 SDK

Introduction

With this tutorial you will learn how to create a fully functional chat as a Single View Application.

The full code of this tutorial is available on GitHub:

DOWNLOAD SOURCE CODE

Prerequisites

Before you begin, you need a few things to set up in your environment:

  • Android Studio 3.0.0 or later

  • Android SDK Build-Tools 26.0.2 or later

  • A Firebase project correctly configured and the Chat21 Firebase cloud functions installed. Detailed instructions here

Firebase setup

Create a Firebase project

Sign up on Firebase and create a project. Please refer directly to Firebase https://firebase.google.com to accomplish and better understand this task. Chat21 relies on Firebase as the backend, so it's really important for you to acquire familiarity with Firebase and all of his services.

Setup the backend for your project

After you successfully created a Firebase project you must setup the backend. Please follow this link to install Chat21 cloud functions on your just created Firebase project.

Configure authentication

Now with the setup of your Firebase project and backend functions installed you can enable email authentication to provide an easy way for your app to sign in with email and password.

Enable email signin in Firebase console:

Create a user to test chat functions:

Choose email and password:

Add the user with “ADD USER” button.

Create Android Studio project

This tutorial will focus on the creation of a simple single view application. In the next tutorial you will approach the creation of a more realistic multi tab application (similar to Whatsapp).

First open Android Studio, select Start a new Android Studio Project and insert the project info using MyChat as project name and insert your team.

NOTE: Take note of the Package name, it will be used in the following steps

Select the Phone and Tablet > API Android 19: 4.4 (Kitkat) as minimum SDK

Select Empty Activity

Insert the Activity and the Layout name

Create the Firebase Android App

Switch on the project on Firebase, go to the Firebase Console > Project Overview and add a Android App to your project by clicking on “Add Android App” and follow the setup steps.

When prompted, enter your app’s Package name (you have pinned previously). It’s important to enter the Package name your app is using, this can only be set when you add an app to your Firebase project.

At the end, you’ll download a google-services.json file. You can download this file again at any time.

Now add this file to your Android project App root

Add Firebase libs to the project

Now go back to your Android project and add firebase libraries to your project.

First, add rules to your root-level build.gradle file, to include the google-services plugin and the Google’s Maven repository:

buildscript {
// ...
dependencies {
// ...
classpath 'com.google.gms:google-services:4.2.0'
}
}
allprojects {
// ...
repositories {
// ...
google()
}
}

Then, in your module Gradle file (usually the app/build.gradle), add the apply plugin line at the bottom of the file to enable the Gradle plugin:

apply plugin: 'com.android.application'
// ...
dependencies {
// ...
implementation "com.google.android.gms:play-services:11.8.0"
}
// ...
apply plugin: 'com.google.gms.google-services'

NOTE: the complete guide to add Firebase libs to you project is available here: https://firebase.google.com/docs/android/setup

Install Chat21 libraries

Add the following to your app/build.gradle file:

defaultConfig {
// ...
multiDexEnabled true
}
dependencies {
// ...
implementation 'com.android.support:multidex:1.0.1'
implementation "com.google.android.gms:play-services:11.8.0"
implementation 'com.android.support:support-v4:28.0.0'
implementation 'com.android.support:design:28.0.0'
implementation 'org.chat21.android:chat21:1.0.15'
implementation 'com.vanniktech:emoji-ios:0.5.1'
implementation 'com.github.bumptech.glide:glide:3.7.0'
implementation 'com.daimajia.swipelayout:library:1.2.0@aar'
}
// ...
configurations.all {
resolutionStrategy.eachDependency { DependencyResolveDetails details ->
def requested = details.requested
if (requested.group == 'com.android.support') {
if (!requested.name.startsWith("multidex")) {
details.useVersion '26.1.0'
}
}
}
}

Create a custom Application class

public class AppContext extends Application {
@Override
protected void attachBaseContext(Context base) {
super.attachBaseContext(base);
MultiDex.install(this); // add this
}
}

and add it to the Manifest.xml

<application
android:name=".AppContext"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme"
...
</application>

Style

Replace the default parent theme in your styles.xml

“Theme.AppCompat.Light.DarkActionBar” with Theme.AppCompat.Light. NoActionBar

<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
<!-- Customize your theme here. -->
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
</style>

Get start with the UI

Copy App ID from your Firebase Project previously created (you can also recover it from your Project Settings)

Add the following code to the onCreate method of your Main Activity and substitute variable in bracket using the previously created user’s email and password and App ID from Firebase Project Settings

FirebaseDatabase.getInstance().setPersistenceEnabled(true);
ChatManager.startWithEmailAndPassword(this, [APP_ID],
[YOUR_EMAIL], [YOUR_PASSWORD], new ChatAuthentication.OnChatLoginCallback() {
@Override
public void onChatLoginSuccess(IChatUser currentUser) {
ChatManager.getInstance().createContactFor(currentUser.getId(), currentUser.getEmail(),
[YOUR_FIRST_NAME], [YOUR_LAST_NAME], new OnContactCreatedCallback() {
@Override
public void onContactCreatedSuccess(ChatRuntimeException exception) {
if (exception == null) {
ChatUI.getInstance().openConversationsListActivity();
} else {
// TODO: handle the exception
}
}
});
}
@Override
public void onChatLoginError(Exception e) {
// TODO: 22/02/18
}
});

Now launch the project.

If everything is correct you will see the conversations’ history with no conversations.

As you can see, in the authWithEmail completion block we use the createContactFor method to create a contact on the remote backend for the currently signed user. In this way every user will add his metadata to contacts as soon as he sign in. The button on the bottom right corner open the contacts list.

You will see yourself listed. If you want you can chat with yourself but it’s better to create another user and sign in on a chat installed on another device (or simulator instance).

Happy chatting 🙂

Feel free to send feedbacks to support@frontiere21.it