Animate Fade In/Fade Out by changing Alpha

Create XML file for fade-in animation, /res/anim/fadein.xml.

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
  android:interpolator="@android:anim/linear_interpolator">
  <alpha
      android:fromAlpha="0.1"
      android:toAlpha="1.0"
      android:duration="2000"
      />
</set>

Create XML file for fade-out animation, /res/anim/fadeout.xml.

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
  android:interpolator="@android:anim/linear_interpolator">
  <alpha
      android:fromAlpha="1.0"
      android:toAlpha="0.1"
      android:duration="2000"
      />
</set>

Modify main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="vertical" >

  <TextView
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="@string/hello" />
  <Button
      android:id="@+id/fadein"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="Fade In"/>
  <Button
      android:id="@+id/fadeout"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="Fade Out"/>
 <LinearLayout
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     android:orientation="vertical"
     android:gravity="center">

     <ImageView
         android:id="@+id/image"
         android:layout_width="fill_parent"
         android:layout_height="fill_parent"
         android:src="@drawable/ic_launcher" />
   
 </LinearLayout>  

</LinearLayout>

main activity

package com.exercise.AndroidAnimTranslate;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ImageView;

public class AndroidAnimTranslateActivity extends Activity {
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
    
      Button buttonFadeIn = (Button)findViewById(R.id.fadein);
      Button buttonFadeOut = (Button)findViewById(R.id.fadeout);
      final ImageView image = (ImageView)findViewById(R.id.image);
    
      final Animation animationFadeIn = AnimationUtils.loadAnimation(this, R.anim.fadein);
      buttonFadeIn.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View arg0) {
    // TODO Auto-generated method stub
    image.startAnimation(animationFadeIn);
   }});
    
      final Animation animationFadeOut = AnimationUtils.loadAnimation(this, R.anim.fadeout);
      buttonFadeOut.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View arg0) {
    // TODO Auto-generated method stub
    image.startAnimation(animationFadeOut);
   }});
  }
}

Download the files.

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