ViewAnimationUtils.java

/*
 * Copyright 2016 Hippo Seven
 *
 * 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.hippo.reveal;

import android.animation.Animator;
import android.animation.ValueAnimator;
import android.annotation.TargetApi;
import android.os.Build;
import android.view.View;

import com.hippo.yorozuya.SimpleAnimatorListener;

public final class ViewAnimationUtils {
    private ViewAnimationUtils() {}

    public static final boolean API_SUPPORT_CIRCULAR_REVEAL =
            Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP;
    // http://developer.android.com/guide/topics/graphics/hardware-accel.html#unsupported
    public static final boolean API_SUPPORT_CANVAS_CLIP_PATH =
            Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2;

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    public static Animator createCircularReveal(View view,
            int centerX,  int centerY, float startRadius, float endRadius) {
        if (API_SUPPORT_CIRCULAR_REVEAL) {
            return android.view.ViewAnimationUtils.createCircularReveal(
                    view, centerX, centerY, startRadius, endRadius);
        } else if (view instanceof Reveal){
            return createRevealAnimator((Reveal) view, centerX, centerY,
                    startRadius, endRadius);
        } else {
            throw new IllegalStateException("Only View implements CircularReveal or" +
                    " api >= 21 can create circular reveal");
        }
    }

    private static Animator createRevealAnimator(Reveal reveal, int centerX, int centerY,
            float startRadius, float endRadius) {
        ValueAnimator animator = ValueAnimator.ofFloat(startRadius, endRadius);
        animator.addUpdateListener(new RevealAnimatorUpdateListener(reveal, centerX, centerY));
        animator.addListener(new RevealAnimatorListener(reveal));
        return animator;
    }

    private static class RevealAnimatorUpdateListener
            implements ValueAnimator.AnimatorUpdateListener {

        private final Reveal mReveal;
        private final int mCenterX;
        private final int mCenterY;

        public RevealAnimatorUpdateListener(Reveal reveal, int centerX, int centerY) {
            mReveal = reveal;
            mCenterX = centerX;
            mCenterY = centerY;
        }

        @Override
        public void onAnimationUpdate(ValueAnimator animation) {
            Object value = animation.getAnimatedValue();
            if (value instanceof Float) {
                mReveal.setReveal(mCenterX, mCenterY, (Float) value);
            }
        }
    }

    private static class RevealAnimatorListener extends SimpleAnimatorListener {

        private final Reveal mReveal;
        private final View mView;

        public RevealAnimatorListener(Reveal reveal) {
            mReveal = reveal;
            mView = (View) reveal;
        }

        @Override
        public void onAnimationStart(Animator animation) {
            if (!API_SUPPORT_CANVAS_CLIP_PATH) {
                mView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
            }
            mReveal.setRevealEnable(true);
        }

        @Override
        public void onAnimationEnd(Animator animation) {
            mReveal.setRevealEnable(false);
            if (!API_SUPPORT_CANVAS_CLIP_PATH) {
                mView.setLayerType(View.LAYER_TYPE_NONE, null);
            }
        }
    }
}