FriendlyChat

Version 1.0 2018/07/12

This repository contains code for the FriendlyChat project in the Firebase in a Weekend: Android by Google Udacity course.

Overview

FriendlyChat is an app that allows users to send and receive text and photos in realtime across platforms.

Device permissions

App needs the following user's permissions to provide the featured functionality

• Request user's permission to read and write to external storage

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

• Request user's permission to access the internet

<uses-permission android:name="android.permission.INTERNET"/>

• Request user's permission to access device network state

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

defaultConfig {
        minSdkVersion 16
        targetSdkVersion 26
    }

• The app prompts the user to log in using email and google signIn
• Upon successfull authentication chat screen is loaded
• App is build upon the following features:
  • send and receive text in realtime across platforms
  • send and receive photos in realtime across platforms
• Some of the words used in a conversation are replaced by emojis 😂 😸

dependencies {
    
    implementation 'com.firebaseui:firebase-ui-auth:4.0.1'
    // Displaying images
    implementation 'com.github.bumptech.glide:glide:4.7.1'
    //noinspection GradleCompatible
    implementation 'com.firebaseui:firebase-ui-auth:4.0.1'
    implementation 'com.google.firebase:firebase-auth:16.0.2'
    implementation 'com.google.firebase:firebase-core:16.0.1'
    implementation 'com.google.firebase:firebase-database:16.0.1'
    implementation 'com.google.firebase:firebase-storage:16.0.1'
    implementation 'com.google.firebase:firebase-messaging:17.1.0'
    implementation 'com.google.firebase:firebase-config:16.0.0'
    }

Features

• SignIn Intent implemented with FirebaseUI

startActivityForResult(
                            AuthUI.getInstance()
                                    .createSignInIntentBuilder()
                                    .setIsSmartLockEnabled(true, true)
                                    .setAvailableProviders(Arrays.asList(
                                            new AuthUI.IdpConfig.EmailBuilder().build(),
                                            new AuthUI.IdpConfig.GoogleBuilder().build()))
                                    .build(),
                            RC_SIGN_IN);

• Uploading choosen photo to Firebase Storage and make a reference to it from the Realtime Database

// Upload file to Firebase Storage
            Uri selectedImageUri = data.getData();

            final StorageReference photoRef =
                    storageReference.child(selectedImageUri.getLastPathSegment());
            photoRef.putFile(selectedImageUri);
            photoRef.putFile(selectedImageUri).continueWithTask(new Continuation<UploadTask.TaskSnapshot, Task<Uri>>() {
                @Override
                public Task<Uri> then(@NonNull Task<UploadTask.TaskSnapshot> task) throws Exception {
                    if (!task.isSuccessful()) {
                        throw task.getException();
                    }
                    return photoRef.getDownloadUrl();
                }
            }).addOnCompleteListener(new OnCompleteListener<Uri>() {
                @Override
                public void onComplete(@NonNull Task<Uri> task) {
                    if (task.isSuccessful()) {
                        Uri downloadUri = task.getResult();
                        FriendlyMessage friendlyMessage = new FriendlyMessage(null, mUsername, downloadUri.toString());
                        databaseReference.push().setValue(friendlyMessage);
                    }
                }
            });

• Configured Remote Configs from Firebase to adjust the variable of the exchanged message length

private void fetchConfig() {
        long cacheExpiration = 3600;

        if (remoteConfig.getInfo().getConfigSettings().isDeveloperModeEnabled()) {
            cacheExpiration = 0;
        }

        remoteConfig.fetch(cacheExpiration).addOnSuccessListener(new OnSuccessListener<Void>() {
            @Override
            public void onSuccess(Void aVoid) {
                remoteConfig.activateFetched();
                applyRetrievedLengthLimit();
            }
        }).addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                Log.d(TAG, "Error fetching config", e);
                applyRetrievedLengthLimit();
            }
        });
    }

• JavaScript function converting some of the text to emoji

const functions = require('firebase-functions');

// replaces keywords with emoji in the "text" key of messages
// pushed to /messages
exports.emojify =
    functions.database.ref('/messages/{pushId}/text')
    .onWrite((change, context) => {
      
        // Now we begin the emoji transformation
        console.log("emojifying!");

        // Get the value from the 'text' key of the message
        const originalText = change.after.val();
        const emojifiedText = emojifyText(originalText);

        // Return a JavaScript Promise to update the database node
        return change.after.ref.set(emojifiedText);
    });

// Returns text with keywords replaced by emoji
// Replacing with the regular expression /.../ig does a case-insensitive
// search (i flag) for all occurrences (g flag) in the string
function emojifyText(text) {
    var emojifiedText = text;
    emojifiedText = emojifiedText.replace(/\blol\b/ig, "😂");
    emojifiedText = emojifiedText.replace(/\bcat\b/ig, "😸");
    return emojifiedText;
}

License

See LICENSE