# Trouble using VTK Widget with QVTK
**URL:** https://discourse.vtk.org/t/trouble-using-vtk-widget-with-qvtk/2110
**Category:** Development
**Created:** [November 20, 2019, 8:42am UTC](https://discourse.vtk.org/t/trouble-using-vtk-widget-with-qvtk/2110 "2019-11-20T08:42:21Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@Andreimd02](https://discourse.vtk.org/u/Andreimd02)
#### Post date: [November 20, 2019, 8:42am UTC](https://discourse.vtk.org/t/trouble-using-vtk-widget-with-qvtk/2110/1 "2019-11-20T08:42:21Z")
Hi, guys,
So, I’m have a trouble to use QVTKRenderWindowInteractor and vtkContourWidget
I have this program
This is how I made it:
class SimulationWindow(QMainWindow):
def **init** (self):
super(). **init** ()
self.initWindow()
```
#VTKInteractor
self.frame = QFrame()
self.vl = QVBoxLayout()
self.vtkWidget = QVTKRenderWindowInteractor(self.frame)
self.vl.addWidget(self.vtkWidget)
##Vtk
self.renderer = vtk.vtkRenderer()
self.vtkWidget.GetRenderWindow().AddRenderer(self.renderer)
#Actors
self.xraysource = buildDiskActor(position=(100, 130))
self.renderer.AddActor(self.xraysource)
self.objects_dic['source'] = self.xraysource
self.object = buildDiskActor(position=(350, 300), color=(0.9, 0.9, 0.9))
self.renderer.AddActor(self.object)
self.objects_dic['object'] = self.object
self.detector = buildCubeActor(position=(500, 400))
self.renderer.AddActor(self.detector)
self.objects_dic['detector'] = self.detector
self.renderer.ResetCamera()
self.frame.setLayout(self.vl)
self.setCentralWidget(self.frame)
#Interactor
self.interactor = self.vtkWidget.GetRenderWindow().GetInteractor()
inStyle = CustomInteractor(self.renderer, self.vtkWidget.GetRenderWindow(), self.objects_dic)
self.interactor.SetInteractorStyle(inStyle)
self.show()
self.interactor.Initialize()
```
obs. My CustomInteractor extends vtkInteractorStyleTrackballActor
Well, when I Right Click on a object, I want to change my interactor to ContourWidget effects
to do this I make this function:
```
def buildCustomTrajectory(self):
render_window = vtk.vtkRenderWindow()
render_window.AddRenderer(self.renderer)
render_interactor = vtk.vtkRenderWindowInteractor()
render_interactor.SetRenderWindow(render_window)
contour_widget = vtk.vtkContourWidget()
contour_widget.SetInteractor(render_interactor)
contour_widget.CreateDefaultRepresentation()
render_interactor.Initialize()
contour_widget.On()
render_window.Render()
render_interactor.Start()
self.renderer.ResetCamera()
```
But when I execute this, he open another window like that:
In the new window ContourWidget is working, but my main window does nothing, and I really want that the contourWidget working in my main window application with QVTK.
I tried many ways to Set vtkRenderWindow to my self.vtkWidget, but only open a new White Window.
I have to put the vtkRenderWindow Because contour widget only accept vtkRenderWindowInteractor, and I have to set a vtkRenderWindow to vtkRenderWindowInteractor.
Someone can help me with this? I’m really stuck here.
I found a problem like mine here [http://vtk.1045678.n5.nabble.com/Trouble-using-VTK-Widget-with-QVTK-td5727389.html](http://vtk.1045678.n5.nabble.com/Trouble-using-VTK-Widget-with-QVTK-td5727389.html)
but in this case he is using c++ and to solve used the class QVTKOpenGlWidget, that I think doesn’t have on python.
My regards.
Python 3.7, vtk 8.2, PyQt5.
---
### Author:  [@dgobbi](https://discourse.vtk.org/u/dgobbi)
#### Post date: [November 21, 2019, 12:23am UTC](https://discourse.vtk.org/t/trouble-using-vtk-widget-with-qvtk/2110/2 "2019-11-21T00:23:32Z")
~~You can try using [QVTKRenderWindowInteractor.py](https://gitlab.kitware.com/vtk/vtk/blob/master/Wrapping/Python/vtkmodules/qt/QVTKRenderWindowInteractor.py), it is a pure-python alternative to QVTKOpenGLWidget.~~
Edit: Oops, it looks like you are already doing this. Sorry for the noise.
---
### Author:  [@Andreimd02](https://discourse.vtk.org/u/Andreimd02)
#### Post date: [November 21, 2019, 4:58am UTC](https://discourse.vtk.org/t/trouble-using-vtk-widget-with-qvtk/2110/3 "2019-11-21T04:58:04Z")
Thank you anyway, I just can`t solve it with QVTKRenderWindowInteractor. Maybe I go to CTK or pyside to do this, but don`t know how yet.
---
### Author:  [@lassoan](https://discourse.vtk.org/u/lassoan)
#### Post date: [November 22, 2019, 2:38pm UTC](https://discourse.vtk.org/t/trouble-using-vtk-widget-with-qvtk/2110/4 "2019-11-22T14:38:36Z")
CTK uses PythonQt for wrapping. PythonQt embeds Python in a C++ application, so you get more control, potentially higher performance, cleaner packaging, etc. but you need to compile your executable (such as the ctkSimplePythonShell example application).