app.philm.in.util.ColorValueAnimator.java Source code

Introduction

Here is the source code for app.philm.in.util.ColorValueAnimator.java

Source

/*
 * Copyright 2014 Chris Banes
 *
 * 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 app.philm.in.util;

import com.google.common.base.Preconditions;

import android.animation.ValueAnimator;
import android.view.View;

public class ColorValueAnimator {

    public interface OnColorSetListener {
        public void onUpdateColor(int[] newColors);
    }

    public static ValueAnimator start(final View rootView, final int[] current, final int[] target,
            final int duration, final OnColorSetListener listener) {

        Preconditions.checkNotNull(rootView, "rootView cannot be null");
        Preconditions.checkNotNull(current, "current cannot be null");
        Preconditions.checkNotNull(target, "target cannot be null");
        Preconditions.checkArgument(current.length == target.length, "current and target must be the same length");

        if (rootView.getDrawingTime() <= 0) {
            listener.onUpdateColor(target);
            return null;
        }

        final int[] colors = new int[target.length];

        ValueAnimator animator = new ValueAnimator();
        animator.setFloatValues(0f, 1f);
        animator.setDuration(duration);
        animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator valueAnimator) {
                final float currentValue = 1f - (Float) valueAnimator.getAnimatedValue();

                for (int i = 0, z = colors.length; i < z; i++) {
                    colors[i] = ColorUtils.blendColors(current[i], target[i], currentValue);
                }

                listener.onUpdateColor(colors);
            }
        });
        animator.start();

        return animator;
    }

}