I want to change qMRMLSubjectHierarchyTreeView implement some functions, but I don’t want to change its source code, so I created a myTreeView inheritance in qMRMLSubjectHierarchyTreeView, now the problem is that I should how the slicer the qMRMLSubjectHierarchyTreeView replace myTreeView
You can either contribute your changes as options in the existing class in Slicer, or you can fork Slicer, in which case the maintenance burden will significantly increase.
What are those functions?
The best way to proceed depends on that, because if those functions are generally useful for Slicer users then it makes sense to maintain them in Slicer core. If those features are only useful for your project then you can use existing infrastructure in subject hierarchy that already allows very flexible customization and extension. If current subject hierarchy customization/extension infrastructure in Slicer core are not sufficient then you can improve that.
Thank you very much I have changed qMRMLSubjectHierarchyTreeView source I want to achieve