错误:参数类型'Set<Marker>?‘不能分配给参数类型'Set<Marker>‘

Question

  onTap: widget.isSelecting ? _selectLocation : null,
          markers: (_pickedLocation == null && widget.isSelecting)
              ? null
              : {
                  Marker(
                    markerId: MarkerId('m1'),
                    position: _pickedLocation ??
                        LatLng(
                          widget.initialLocation.latitude,
                          widget.initialLocation.longitude,
                        ),
                  ),
                }),

Answer 1

要么将markers变为可空的，即Set<Marker>? markers

或

如果此条件为真(_pickedLocation == null && widget.isSelecting)，则传递空集而不是null