anchor.diff:  
     /// Mirror to [PhotoView.tightMode]
     final bool tightMode;
  +
  +  /// Mirror to [PhotoView.disableGestures]
  +  final bool disableGestures;
   
     /// Quality levels for image filters.
     final FilterQuality filterQuality;
  
positive.code:             tightMode: pageOption.tightMode,
              filterQuality: pageOption.filterQuality,
              basePosition: pageOption.basePosition,
            )
          : PhotoView(
              key: ObjectKey(index),
  
negative.code:     this.gestureDetectorBehavior,
      this.tightMode,
      this.filterQuality,
      this.disableGestures,
    })  : imageProvider = null,
          assert(child != null);
  
  