src/com/android/launcher3/views/IconButtonView.java

/*
 * Copyright (C) 2022 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.launcher3.views;

import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BlendMode;
import android.graphics.BlendModeColorFilter;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Rect;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.util.AttributeSet;

import com.android.launcher3.BubbleTextView;
import com.android.launcher3.icons.BaseIconFactory;
import com.android.launcher3.icons.FastBitmapDrawable;
import com.android.launcher3.icons.LauncherIcons;

/**
 * Button in Taskbar that shows a tinted background and foreground.
 */
public class IconButtonView extends BubbleTextView {

    private static final int[] ATTRS = {android.R.attr.icon};

    public IconButtonView(Context context) {
        this(context, null);
    }

    public IconButtonView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public IconButtonView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

        TypedArray a = context.obtainStyledAttributes(attrs, ATTRS, defStyle, 0);
        Drawable fg = a.getDrawable(0);
        a.recycle();

        ColorStateList tintList = getBackgroundTintList();
        int tint = tintList == null ? Color.WHITE : tintList.getDefaultColor();

        if (fg == null) {
            fg = new ColorDrawable(Color.TRANSPARENT);
        }
        try (BaseIconFactory factory = LauncherIcons.obtain(context)) {
            setIcon(new IconDrawable(factory.getWhiteShadowLayer(), tint, fg));
        }
    }

    private static class IconDrawable extends FastBitmapDrawable {

        private final Drawable mFg;

        @TargetApi(Build.VERSION_CODES.TIRAMISU)
        IconDrawable(Bitmap b, int colorBg, Drawable fg) {
            super(b);
            mPaint.setColorFilter(new BlendModeColorFilter(colorBg, BlendMode.SRC_IN));
            mFg = fg;
        }

        @Override
        protected void drawInternal(Canvas canvas, Rect bounds) {
            super.drawInternal(canvas, bounds);
            mFg.draw(canvas);
        }

        @Override
        protected void onBoundsChange(Rect bounds) {
            super.onBoundsChange(bounds);
            mFg.setBounds(bounds);
        }
    }
}