com.facebook.litho.reference.ColorDrawableReference.java Source code

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Here is the source code for com.facebook.litho.reference.ColorDrawableReference.java

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/**
 * Copyright (c) 2017-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

package com.facebook.litho.reference;

import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.support.annotation.AttrRes;
import android.support.annotation.ColorRes;
import android.support.v4.util.Pools;

import com.facebook.litho.ComponentContext;
import com.facebook.litho.config.ComponentsConfiguration;

/**
 * A Reference for {@link ColorDrawable}. This keeps a {@link Pools.Pool} of up to 10 ColorDrawable
 * and allows to specify color and alpha as create.
 */
public final class ColorDrawableReference extends ReferenceLifecycle<Drawable> {

    private static final int DEFAULT_ALPHA = 255;
    private static final int INITIAL_POOL_SIZE = 50;
    // setColor() was introduced only in Honeycomb.
    private static final boolean CAN_RECYCLE = Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB;

    private static ColorDrawableReference sInstance;

    private static final Pools.SynchronizedPool<PropsBuilder> mBuilderPool = new Pools.SynchronizedPool<PropsBuilder>(
            2);

    private static final Pools.Pool<ColorDrawable> sPool = CAN_RECYCLE
            ? new Pools.SynchronizedPool<ColorDrawable>(INITIAL_POOL_SIZE)
            : null;

    private ColorDrawableReference() {
    }

    public static synchronized ColorDrawableReference get() {
        if (sInstance == null) {
            sInstance = new ColorDrawableReference();
        }

        return sInstance;
    }

    private static PropsBuilder newBuilder(ComponentContext context, State state) {
        PropsBuilder builder = mBuilderPool.acquire();
        if (builder == null) {
            builder = new PropsBuilder();
        }

        builder.init(context, state);

        return builder;
    }

    public static PropsBuilder create(ComponentContext c) {
        return newBuilder(c, new State());
    }

    @Override
    protected Drawable onAcquire(ComponentContext context, Reference reference) {
        ColorDrawable drawable = null;

        if (CAN_RECYCLE) {
            drawable = sPool.acquire();
        }

        if (drawable == null) {
            drawable = new ColorDrawable(((State) reference).mColor);
        } else {
            drawable.setColor(((State) reference).mColor);
        }

        drawable.setAlpha(((State) reference).mAlpha);

        return drawable;
    }

    @Override
    protected void onRelease(ComponentContext context, Drawable drawable, Reference reference) {
        if (CAN_RECYCLE) {
            sPool.release((ColorDrawable) drawable);
        }
    }

    private static class State extends Reference<Drawable> {

        int mColor;
        int mAlpha = DEFAULT_ALPHA;

        @Override
        public String getSimpleName() {
            return "ColorDrawableReference";
        }

        protected State() {
            super(get());
        }

        @Override
        public int hashCode() {
            int result = mColor;
            result = 31 * result + mAlpha;
            return result;
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) {
                return true;
            }

            if (o == null || getClass() != o.getClass()) {
                return false;
            }

            State state = (State) o;

            if (mColor != state.mColor) {
                return false;
            }

            return mAlpha == state.mAlpha;
        }
    }

    public static class PropsBuilder extends Reference.Builder<Drawable> {

        private State mState;
        private ComponentContext mContext;

        protected void init(ComponentContext context, State state) {
            super.init(context, state);
            mState = state;
            mContext = context;
        }

        @Override
        protected void release() {
            super.release();

            mState = null;
            mContext = null;
            mBuilderPool.release(this);
        }

        public PropsBuilder color(int color) {
            mState.mColor = color;
            return this;
        }

        public PropsBuilder colorRes(@ColorRes int resId) {
            mState.mColor = resolveColorRes(resId);
            return this;
        }

        public PropsBuilder colorAttr(@AttrRes int attrResId, @ColorRes int defResId) {
            mState.mColor = resolveColorAttr(attrResId, defResId);
            return this;
        }

        public PropsBuilder colorAttr(@AttrRes int attrResId) {
            mState.mColor = resolveColorAttr(attrResId, 0);
            return this;
        }

        public PropsBuilder alpha(int alpha) {
            mState.mAlpha = alpha;
            return this;
        }

        @Override
        public Reference<Drawable> build() {
            State state = mState;

            release();

            return state;
        }
    }
}