Implement Animation using Java code

This exercise have the same output as last exercise "Implement swiping page effect using GestureDetector and ViewFlipper", with animations implemented using Java code instead of XML.

Remove /res/anim folder and the XML animation files.

Modify AndroidViewFlipperActivity.java, implement AnimationSet animSetFlipInForeward, animSetFlipOutForeward, animSetFlipInBackward and animSetFlipOutBackward; to replace animFlipInForeward, animFlipOutForeward, animFlipInBackward and animFlipOutBackward.

package com.exercise.AndroidViewFlipper;

import android.app.Activity;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.MotionEvent;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.OvershootInterpolator;
import android.view.animation.TranslateAnimation;
import android.widget.ViewFlipper;

public class AndroidViewFlipperActivity extends Activity {

ViewFlipper page;

  AnimationSet animSetFlipInForeward;
  AnimationSet animSetFlipOutForeward;
  AnimationSet animSetFlipInBackward;
  AnimationSet animSetFlipOutBackward;

  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
    
      page = (ViewFlipper)findViewById(R.id.flipper);
    
      animSetFlipInForeward = new AnimationSet(true);
      TranslateAnimation translateAnimFlipInForeward
      = new TranslateAnimation(
       Animation.RELATIVE_TO_SELF, 1f,
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, 0);
      animSetFlipInForeward.addAnimation(translateAnimFlipInForeward);
      animSetFlipInForeward.setDuration(500);
      animSetFlipInForeward.setInterpolator(new OvershootInterpolator());
    
      animSetFlipOutForeward = new AnimationSet(true);
      TranslateAnimation translateAnimFlipOutForeward
      = new TranslateAnimation(
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, -1f,
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, 0);
      animSetFlipOutForeward.addAnimation(translateAnimFlipOutForeward);
      animSetFlipOutForeward.setDuration(500);
      animSetFlipOutForeward.setInterpolator(new OvershootInterpolator());
    
      animSetFlipInBackward = new AnimationSet(true);
      TranslateAnimation translateAnimFlipInBackward
      = new TranslateAnimation(
       Animation.RELATIVE_TO_SELF, -1f,
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, 0);
      animSetFlipInBackward.addAnimation(translateAnimFlipInBackward);
      animSetFlipInBackward.setDuration(500);
      animSetFlipInBackward.setInterpolator(new OvershootInterpolator());
    
      animSetFlipOutBackward = new AnimationSet(true);
      TranslateAnimation translateAnimFlipOutBackward
      = new TranslateAnimation(
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, 1f,
       Animation.RELATIVE_TO_SELF, 0,
       Animation.RELATIVE_TO_SELF, 0);
      animSetFlipOutBackward.addAnimation(translateAnimFlipOutBackward);
      animSetFlipOutBackward.setDuration(500);
      animSetFlipOutBackward.setInterpolator(new OvershootInterpolator());
    
  }

  private void SwipeRight(){
   page.setInAnimation(animSetFlipInBackward);
 page.setOutAnimation(animSetFlipOutBackward);
 page.showPrevious();
  }

  private void SwipeLeft(){
   page.setInAnimation(animSetFlipInForeward);
 page.setOutAnimation(animSetFlipOutForeward);
 page.showNext();
  }

  @Override
public boolean onTouchEvent(MotionEvent event) {
 // TODO Auto-generated method stub
   return gestureDetector.onTouchEvent(event);
}

SimpleOnGestureListener simpleOnGestureListener
  = new SimpleOnGestureListener(){

 @Override
 public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
   float velocityY) {

  float sensitvity = 50;
  if((e1.getX() - e2.getX()) > sensitvity){
   SwipeLeft();
  }else if((e2.getX() - e1.getX()) > sensitvity){
   SwipeRight();
  }
 
  return true;
 }
  
  };

  GestureDetector gestureDetector
= new GestureDetector(simpleOnGestureListener);
}