android中向bitmap里写入文字

public static Bitmap drawText2Bitmap(String text, int imgResourceId, Context mContext) {
        try {
            Resources resources = mContext.getResources();
            float scale = resources.getDisplayMetrics().density;
            Bitmap bitmap = BitmapFactory.decodeResource(resources, imgResourceId);

            android.graphics.Bitmap.Config bitmapConfig = bitmap.getConfig();
            // set default bitmap config if none
            if (bitmapConfig == null) bitmapConfig = android.graphics.Bitmap.Config.ARGB_8888;
            // resource bitmaps are imutable, so we need to convert it to mutable one
            bitmap = bitmap.copy(bitmapConfig, true);

            Canvas canvas = new Canvas(bitmap);
            Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG); // new antialised Paint
            paint.setColor(Color.rgb(110, 110, 110));       // text color - #3D3D3D
            paint.setTextSize((int)(12 * scale));           // text size in pixels
            paint.setShadowLayer(1f, 0f, 1f, Color.DKGRAY); // text shadow

            // draw text to the Canvas center
            Rect bounds = new Rect();
            paint.getTextBounds(text, 0, text.length(), bounds);
            int x = (bitmap.getWidth() - bounds.width()) / 6;
            int y = (bitmap.getHeight() + bounds.height()) / 5;

            canvas.drawText(text, x * scale, y * scale, paint);
            return bitmap;
        } catch (Exception e) {
            return null;
        }
    }