How to programmatically add the vtkSeedWidget or vtkSphereWidget

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1

How to programmatically add the vtkSeedWidget or vtkSphereWidget,then execute widgetManager.enablePicking(), and you can drag the widget with the mouse

Thanks.

2

Isn’t placeWidget working ?

3

My requirement is for the program to automatically generate the vtkSeedWidget upon loading, rather than requiring a mouse click to do so