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.


  • 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 !



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

Android supported Java8 features


  • default and static methods in Interfaces
    • default and static methods can be declared in Interfaces declarations. These methods don't need to be implemented by the Classes that are implementing those interfaces. static methods are attached to the Interface and Classes which implements such interfaces.
    • Reference: https://docs.oracle.com/javase/tutorial/java/IandI/defaultmethods.html
  • Repeating Annotations
    • Now one annotation can be used multiple times on a specific target.
    • Reference: https://docs.oracle.com/javase/tutorial/java/annotations/repeating.html
  • Lambda expressions:
    • Lambda expressions enable to treat functionality as method argument or code as data.
    • Lambda exp is useful especially to define anonymous class with one method
    • Reference: https://docs.oracle.com/javase/tutorial/java/javaOO/lambdaexpressions.html
    • Syntax for Lambda expressions: https://docs.oracle.com/javase/tutorial/java/javaOO/lambdaexpressions.html#syntax

Terms:
  • Functional interfaces: An interface with only method is called as functional interfaces. JDK defines few built-in functional interfaces in package: java.util.function 

Scheduling Repeating Local Notifications using Alarm Manager

Learn about Scheduling Repeating Local Notifications using Alarm Manager in this post .