SliverPhysicalParentData constructor Null safety

1. Flutter
2. rendering
3. SliverPhysicalParentData
4. SliverPhysicalParentData constructor

SliverPhysicalParentData class

1. Constructors
2. SliverPhysicalParentData
3. Properties
4. hashCode
5. paintOffset
6. runtimeType
7. Methods
8. applyPaintTransform
9. detach
10. noSuchMethod
11. toString
12. Operators
13. operator ==