How to create Animated Gradient Background in android.

AndroidApps/ApplicationsMobile Development

Before getting into example, we should know what is Gradient color. According to Wikipedia, In computer graphics, a color gradient (sometimes called a color ramp or color progression) specifies a range of position-dependent colors, usually used to fill a region. For example, many window managers allow the screen background to be specified as a gradient.

This example demonstrate about how to create Animated Gradient Background in android.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version = "1.0" encoding = "utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android = "http://schemas.android.com/apk/res/android"
   xmlns:app = "http://schemas.android.com/apk/res-auto"
   xmlns:tools = "http://schemas.android.com/tools"
   android:id = "@+id/constraintLayout"
   android:layout_width = "match_parent"
   android:layout_height = "match_parent"
   android:background = "@drawable/gradient_animation "
   tools:context = ".MainActivity">
   <!-- Your layout here -->
   <TextView
      android:layout_width = "368dp"
      android:layout_height = "520dp"
      android:layout_marginBottom = "8dp"
      android:layout_marginLeft = "8dp"
      android:layout_marginRight = "8dp"
      android:layout_marginTop = "8dp"
      android:gravity = "center"
      android:text = "@string/app_name"
      android:textAlignment = "center"
      android:textColor = "@android:color/background_light"
      android:textSize = "30sp"
      android:textStyle = "bold"
      app:layout_constraintBottom_toBottomOf = "parent"
      app:layout_constraintLeft_toLeftOf = "parent"
      app:layout_constraintRight_toRightOf = "parent"
      app:layout_constraintTop_toTopOf = "parent"
      tools:text = "@string/app_name"/>
</android.support.constraint.ConstraintLayout>

In the above code we have added background as gradient_animation in drawable. now create gradient_animation.xml in drawable folder and add the following code -

<?xml version = "1.0" encoding = "utf-8"?>
<animation-list xmlns:android = "http://schemas.android.com/apk/res/android">
   <item
      android:drawable = "@drawable/drawable_purple_gradient"
      android:duration = "3000" />
   <item
      android:drawable = "@drawable/drawable_amber_gradient"
      android:duration = "3000" />
   <item
      android:drawable = "@drawable/drawable_green_gradient"
      android:duration = "3000" />
   <item
      android:drawable = "@drawable/drawable_red_gradient"
      android:duration = "3000" />
</animation-list>

In the above animation-list, we have added 4 child drawables and added duration for each animation view, After time out, it will change the background. In drawable_purple_gradient, contain purple colored background so create a file called drawable_purple_gradient.xml in drawable folder and add the following code -

<?xml version = "1.0" encoding = "utf-8"?>
<shape xmlns:android = "http://schemas.android.com/apk/res/android">
   <gradient
      android:angle = "90"
      android:endColor = "#D500F9"
      android:startColor = "#4A148C" />
</shape>

As follows above step, create drawable_amber_gradient.xml, drawable_green_gradient.xml and drawable_red_gradient.xml in Drawable folder and add the following code as shown below -

drawable_amber_gradient.xml-

<?xml version = "1.0" encoding = "utf-8"?>
<shape xmlns:android = "http://schemas.android.com/apk/res/android">
   <gradient
      android:angle = "135"
      android:endColor = "#FFC400"
      android:startColor = "#FF6F00" />
</shape>

drawable_green_gradient.xml -

<?xml version = "1.0" encoding = "utf-8"?>
<shape xmlns:android = "http://schemas.android.com/apk/res/android">
   <gradient
      android:angle = "0"
      android:endColor = "#00E676"
      android:startColor = "#1B5E20"/>
</shape>

drawable_red_gradient.xml -

<?xml version = "1.0" encoding = "utf-8"?>
<shape xmlns:android = "http://schemas.android.com/apk/res/android">
   <gradient
      android:angle = "45"
      android:endColor = "#FF1744"
      android:startColor = "#B71C1C" />
</shape>

Step 3 − Add the following code to src/MainActivity.java-

package com.example.andy.myapplication;

import android.graphics.drawable.AnimationDrawable;
import android.support.constraint.ConstraintLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {
   private ConstraintLayout constraintLayout;
   private AnimationDrawable animationDrawable;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      constraintLayout = (ConstraintLayout) findViewById(R.id.constraintLayout);
      animationDrawable = (AnimationDrawable) constraintLayout.getBackground();
      animationDrawable.setEnterFadeDuration(3000);
      animationDrawable.setExitFadeDuration(2000);
   }
   @Override
   protected void onResume() {
      super.onResume();
      if (animationDrawable ! = null && !animationDrawable.isRunning()) {
         animationDrawable.start();
      }
   }
   @Override
   protected void onPause() {
      super.onPause();
      if (animationDrawable ! = null && animationDrawable.isRunning()) {
         animationDrawable.stop();
      }
   }
}

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project's activity files and click Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −

 



As shown the above result every 3 sec's. it will change the background color.

Click here to download the project code

raja
Published on 29-Jan-2019 12:23:04
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