图片上动态添加文字

android上在图片上动态添加文字的方法：

 public Bitmap drawTextToBitmap(Context gContext,
   int gResId,
   String gText) {
   Resources resources = gContext.getResources();
   float scale = resources.getDisplayMetrics().density;
   Bitmap bitmap =
       BitmapFactory.decodeResource(resources, gResId);

   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);
   // new antialised Paint
   Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
   // text color - #3D3D3D
   paint.setColor(Color.rgb(61, 61, 61));
   // text size in pixels
   paint.setTextSize((int) (14 * scale));
   // text shadow
   paint.setShadowLayer(1f, 0f, 1f, Color.WHITE);

   // draw text to the Canvas center
   Rect bounds = new Rect();
   paint.getTextBounds(gText, 0, gText.length(), bounds);
   int x = (bitmap.getWidth() - bounds.width())/2;
   int y = (bitmap.getHeight() + bounds.height())/2;

   canvas.drawText(gText, x * scale, y * scale, paint);

   return bitmap;
 }