Use custom drawable for Recents Go thumbnails (1/2)

/*

 * Copyright (C) 2019 The Android Open Source Project

 *

 * 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.android.quickstep;

import android.graphics.Bitmap;

import android.graphics.Canvas;

import android.graphics.ColorFilter;

import android.graphics.Matrix;

import android.graphics.Paint;

import android.graphics.PixelFormat;

import android.graphics.Rect;

import android.graphics.drawable.Drawable;

import androidx.annotation.NonNull;

import com.android.systemui.shared.recents.model.ThumbnailData;

/**

 * Bitmap backed drawable that supports rotating the thumbnail bitmap depending on if the

 * orientation the thumbnail was taken in matches the desired orientation. In addition, the

 * thumbnail always fills into the containing bounds.

 */

public final class ThumbnailDrawable extends Drawable {

    private final Paint mPaint = new Paint();

    private final Matrix mMatrix = new Matrix();

    private final ThumbnailData mThumbnailData;

    private int mRequestedOrientation;

    public ThumbnailDrawable(@NonNull ThumbnailData thumbnailData, int requestedOrientation) {

        mThumbnailData = thumbnailData;

        mRequestedOrientation = requestedOrientation;

        updateMatrix();

    }

    /**

     * Set the requested orientation.

     *

     * @param orientation the orientation we want the thumbnail to be in

     */

    public void setRequestedOrientation(int orientation) {

        if (mRequestedOrientation != orientation) {

            mRequestedOrientation = orientation;

            updateMatrix();

        }

    }

    @Override

    public void draw(Canvas canvas) {

        if (mThumbnailData.thumbnail == null) {

            return;

        }

        canvas.drawBitmap(mThumbnailData.thumbnail, mMatrix, mPaint);

    }

    @Override

    protected void onBoundsChange(Rect bounds) {

        super.onBoundsChange(bounds);

        updateMatrix();

    }

    @Override

    public void setAlpha(int alpha) {

        final int oldAlpha = mPaint.getAlpha();

        if (alpha != oldAlpha) {

            mPaint.setAlpha(alpha);

            invalidateSelf();

        }

    }

    @Override

    public int getAlpha() {

        return mPaint.getAlpha();

    }

    @Override

    public void setColorFilter(ColorFilter colorFilter) {

        mPaint.setColorFilter(colorFilter);

        invalidateSelf();

    }

    @Override

    public ColorFilter getColorFilter() {

        return mPaint.getColorFilter();

    }

    @Override

    public int getOpacity() {

        return PixelFormat.TRANSLUCENT;

    }

    private void updateMatrix() {

        if (mThumbnailData.thumbnail == null) {

            return;

        }

        mMatrix.reset();

        float scaleX;

        float scaleY;

        Rect bounds = getBounds();

        Bitmap thumbnail = mThumbnailData.thumbnail;

        if (mRequestedOrientation != mThumbnailData.orientation) {

            // Rotate and translate so that top left is the same.

            mMatrix.postRotate(90, 0, 0);

            mMatrix.postTranslate(thumbnail.getHeight(), 0);

            scaleX = (float) bounds.width() / thumbnail.getHeight();

            scaleY = (float) bounds.height() / thumbnail.getWidth();

        } else {

            scaleX = (float) bounds.width() / thumbnail.getWidth();

            scaleY = (float) bounds.height() / thumbnail.getHeight();

        }

        // Scale to fill.

        mMatrix.postScale(scaleX, scaleY);

    }

}