IconFactory.java

/*
 * Copyright (C) 2015 AChep@xda <artemchep@gmail.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA  02110-1301, USA.
 */
package com.achep.acdisplay.graphics;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.drawable.Drawable;
import android.support.annotation.NonNull;
import android.util.Log;

import com.achep.acdisplay.R;
import com.achep.acdisplay.notifications.NotificationUtils;
import com.achep.acdisplay.notifications.OpenNotification;
import com.achep.base.utils.RefCacheBase;
import com.achep.base.utils.ResUtils;

import java.lang.ref.Reference;
import java.lang.ref.WeakReference;

import static com.achep.base.Build.DEBUG;

/**
 * The factory for generating the notification icons.
 *
 * @author Artem Chepurnoy
 */
public class IconFactory {

    private static final String TAG = "IconFactory";

    private static final RefCacheBase<Bitmap> ICONS_CACHE = new RefCacheBase<Bitmap>() {
        @NonNull
        @Override
        protected Reference<Bitmap> onCreateReference(@NonNull Bitmap object) {
            return new WeakReference<>(object);
        }
    };

    public static Bitmap generate(final @NonNull Context context,
                                  final @NonNull OpenNotification notification) {
        final int iconRes = notification.getNotification().icon;
        String packageName = notification.getPackageName();
        String cacheKey = packageName + "<drawable>" + iconRes;

        // Check the cache before generating the new icon
        Bitmap bitmap = ICONS_CACHE.get(cacheKey);
        if (bitmap != null) {
            if (DEBUG) Log.d(TAG, "Got the icon of notification from cache: key=" + cacheKey);
            return bitmap;
        }

        Resources res = context.getResources();
        Drawable drawable = NotificationUtils.getDrawable(context, notification, iconRes);
        final int size = res.getDimensionPixelSize(R.dimen.notification_icon_size);
        if (drawable != null) {
            bitmap = createIcon(drawable, size);
            ICONS_CACHE.put(cacheKey, bitmap);
            if (DEBUG) Log.d(TAG, "Put the icon of notification to cache: key=" + cacheKey);
        } else {
            bitmap = createEmptyIcon(context, size);
        }

        return bitmap;
    }

    // TODO: Automatically scale the icon.
    @NonNull
    private static Bitmap createIcon(@NonNull Drawable drawable, int size) {
        Bitmap icon = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_4444);
        Canvas canvas = new Canvas(icon);

        // Calculate scale ratios
        int drawableWidth = drawable.getIntrinsicWidth();
        int drawableHeight = drawable.getIntrinsicHeight();
        float ratioX = Math.min((float) drawableWidth / drawableHeight, 1f);
        float ratioY = Math.min((float) drawableHeight / drawableWidth, 1f);

        // Calculate new width and height
        int width = Math.round(size * ratioX);
        int height = Math.round(size * ratioY);
        int paddingLeft = (size - width) / 2;
        int paddingTop = (size - height) / 2;

        // Apply size and draw
        canvas.translate(paddingLeft, paddingTop);
        drawable = drawable.mutate();
        drawable.setBounds(0, 0, width, height);
        drawable.draw(canvas);

        return icon;
    }

    @NonNull
    private static Bitmap createEmptyIcon(@NonNull Context context, int size) {
        Paint paint = new Paint();
        paint.setAntiAlias(true);
        paint.setColor(0xDDCCCCCC); // white gray

        final float radius = size / 2f;

        Bitmap icon = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_4444);
        Canvas canvas = new Canvas(icon);
        canvas.drawCircle(radius, radius, radius, paint);

        Drawable drawable = ResUtils.getDrawable(context, R.drawable.ic_action_warning_white);
        assert drawable != null;
        drawable.setBounds(0, 0, size, size);
        drawable.draw(canvas);

        return icon;
    }

}