/**
  * Set or clear the paint's colorfilter, returning the parameter.
  *
  * @param filter May be null. The new filter to be installed in the paint
  * @return filter
  */
 public ColorFilter setColorFilter(ColorFilter filter) {
   int filterNative = 0;
   if (filter != null) filterNative = filter.native_instance;
   native_setColorFilter(mNativePaint, filterNative);
   mColorFilter = filter;
   return filter;
 }