Thanks for you reply. However, even I change it to SetInputDataObject, it shows the following errors:
vtkCompositeDataPipelin:143 ERR| vtkCompositeDataPipeline (0x112f78dbc20): Can not execute simple algorithm vtkDataSetMapper (0x112f7953b70) without output ports
ERROR: In vtkCompositeDataPipeline.cxx, line 143
vtkCompositeDataPipeline (0x112f78dbc20): Can not execute simple algorithm vtkDataSetMapper (0x112f7953b70) without output ports
My changes show as following.
vtkNew partionDataSetColl;
partionDataSetColl->SetNumberOfPartitionedDataSets(2);
partionDataSetColl->SetPartitionedDataSet(0, partionDataSet1);
partionDataSetColl->SetPartitionedDataSet(1, partionDataSet2);
vtkNew mapper;
mapper->SetInputDataObject(partionDataSetColl);
vtkNew actor;
actor->SetMapper(mapper);
renderer->AddActor(actor);