FadeAnimation.java

/*
 * Copyright (C) 2014 Saravan Pantham
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.jams.music.player.Animations;

import android.view.View;
import android.view.animation.AlphaAnimation;
import android.view.animation.Animation;
import android.view.animation.Interpolator;

/**
 * Fade animation class. Pass in any view to apply 
 * the animation.
 * 
 * @author Saravan Pantham
 */
public class FadeAnimation extends AlphaAnimation {

	private View mView;
	private long mDuration;
	private float mFromAlpha;
	private float mToAlpha;
	private Interpolator mInterpolator;
	
	public FadeAnimation(View view, long duration, float fromAlpha, 
						 float toAlpha, Interpolator interpolator) {
		
		super(fromAlpha, toAlpha);
		mView = view;
		mDuration = duration;
		mFromAlpha = fromAlpha;
		mToAlpha = toAlpha;
		mInterpolator = interpolator;
		
	}

	/**
	 * Performs the fade animation.
	 */
	public void animate() {
		
		if (mView==null)
			return;
		
		if (mFromAlpha==mToAlpha)
			return;
		
		if (mDuration==0)
			return;
		
		//Set the animation parameters.
		if (mFromAlpha > mToAlpha)
			//Fade out animation.
			this.setAnimationListener(fadeOutListener);
		else
			//Fade in animation.
			this.setAnimationListener(fadeInListener);
		
		this.setDuration(mDuration);
        if (mInterpolator!=null)
		    this.setInterpolator(mInterpolator);
		mView.startAnimation(this);

	}
	
	/**
	 * Fade in animation listener.
	 */
	private AnimationListener fadeInListener = new AnimationListener() {

		@Override
		public void onAnimationEnd(Animation arg0) {
			mView.setVisibility(View.VISIBLE);
			
		}

		@Override
		public void onAnimationRepeat(Animation arg0) {
			// TODO Auto-generated method stub
			
		}

		@Override
		public void onAnimationStart(Animation arg0) {
			mView.setVisibility(View.INVISIBLE);
			
		}
		
	};
	
	/**
	 * Fade out animation listener.
	 */
	private AnimationListener fadeOutListener = new AnimationListener() {

		@Override
		public void onAnimationEnd(Animation arg0) {
			mView.setVisibility(View.INVISIBLE);
			
		}

		@Override
		public void onAnimationRepeat(Animation arg0) {
			// TODO Auto-generated method stub
			
		}

		@Override
		public void onAnimationStart(Animation arg0) {
			mView.setVisibility(View.VISIBLE);
			
		}
		
	};
	
}