Daily Learnings

Safe Installing from Web on Mac OSX

Step 1: You should have md5 tool setup to verify installer/file downloaded from web.

brew install md5sha1sum

Step 2: Check downloaded file like this:

md5sum <path-to-file-to-be-verified>

Android Studio: Files to keep in version control

Here's list of files that should be kept under version control like Git:

compiler.xml
encodings.xml
modules.xml
*.ipr : Contains project related data.

File to be included in gitignore OR not to be kept under version control:

workspace.xml
*.iws : Contains user specific data.

Tinkering with Physical Web (Android)

How to convert a device into beacon (Device 1)

Install Beacon Toy application on device that you want to convert/use as beacon.
Enable data (wifi or cellular and bluetooth on this device)
Configure URL in Beacon Toy application. You also have option to choose to get a short url.
I'm using my blog's url for this testing purpose.

How to enable physical web on your device (Device 2)

Enable data, location and bluetooth
Open Chrome and turn on Physical Web

Chrome --> Settings --> Privacy --> Physical Web

Download Physical Web app from Play Store.
Open Physical Web app.

It'll start scanning all the nearby beacons.
It'll pick up Device 1's transmitted url and open my blog :)

Tinkering with Firebase: Notifications

Here are quick steps/tips to integrate Firebase notifications in your client app:

AndroidManifest :

<application>
.....
.....
    <service        android:name=".MyFirebaseMessagingService">
        <intent-filter>
            <action android:name="com.google.firebase.MESSAGING_EVENT"/>
        </intent-filter>
    </service>
    
    <service        android:name=".MyFirebaseInstanceIdService">
        <intent-filter>
            <action android:name="com.google.firebase.INSTANCE_ID_EVENT"/>
        </intent-filter>
    </service>
    
</application>

app/build.gradle:

dependencies {
    compile 'com.google.firebase:firebase-messaging:9.0.2'}

//Make sure to apply it at the end of the file
apply plugin: 'com.google.gms.google-services'

Project level build.gradle:

dependencies {
    classpath 'com.google.gms:google-services:3.0.0'
}

New Classes:

class MyFirebaseMessagingService extends FirebaseMessagingService:

This is where notifications rendering is handled.

Method responsible for message handling:

@Overridepublic void onMessageReceived(RemoteMessage remoteMessage) {}

class MyFirebaseInstanceIdService extends FirebaseInstanceIdService

This class is useful in getting the device token. This token is used if you want to send message to that particular device.
This token can be collected: FirebaseInstanceId.getInstance().getToken() during app initialization.

Firebase console:

Go to Firebase Console to configure notifications: https://console.firebase.google.com/project/<projectId>/notification
Configure and start send notifications !

Side Notes:

You app should be signed setup for using Firebase by generating and copying google-services.json under your app/ folder.
You'll get opportunity to download google-services.json while configuring your Firebase Notifications via Firebase Console.
New SHA can be added from Setting tabs under chosen project.

How to keep Multi-Dex issue away !

Tip 1: Always keep an check on library's method count using these two tools:

Tip 2: Use Proguard for debug builds as well.

Configuring gradle plug-in:

Global build.gradle:

classpath 'com.getkeepsafe.dexcount:dexcount-gradle-plugin:0.5.0'

Local : app/build.gradle

apply plugin: 'com.android.library'

//AFTER android or library pluginapply plugin: 'com.getkeepsafe.dexcount'

References:

http://jeroenmols.com/blog/2016/05/06/methodcount

Rx-Android sample code

There's lots of fuss around Rx/functional programming these day. I wanted to learn by doing, but couldn't find any simple example code to get me started. There're plenty of information for advanced programmers, but nothing basic. So I'm sharing a very simple sample app that uses Rx-Android to do the same thing that an AsyncTask would do. Checkout README for more details.

Source code is here: https://github.com/ptyagi911/rx-android-examples

Super Simple example code for Android Fragment

Looking for easy to follow code to understand Fragments in Android ? You're at right place ! Checkout this sample code in github: https://github.com/ptyagi911/android-fragments-example