# How to update ArraySelectionDomain based on selected time?

**URL:** https://discourse.paraview.org/t/how-to-update-arrayselectiondomain-based-on-selected-time/15789
**Category:** ParaView Support
**Created:** [November 26, 2024, 2:57pm UTC](https://discourse.paraview.org/t/how-to-update-arrayselectiondomain-based-on-selected-time/15789 "2024-11-26T14:57:29Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![SBl](https://discourse.paraview.org/user_avatar/discourse.paraview.org/sbl/32/12118_2.png) [@SBl](https://discourse.paraview.org/u/SBl)
#### Post date: [November 26, 2024, 2:57pm UTC](https://discourse.paraview.org/t/how-to-update-arrayselectiondomain-based-on-selected-time/15789/1 "2024-11-26T14:57:29Z")

</div>

I am writing a python plugin which should show different properties in an ArraySelectionDomain depending on which time step is currently selected in Paraview. I have tried but I cannot seem to figure out how to update the ArraySelectionDomain when selecting a new time step. I have made a small mock-up example below, but this does not update the array selection domain when switching time steps. Instead, it updates the list when I select/deselect an entry in the array selection domain and press apply. My desired behaviour is as follows:

If the selected time = 0, the selectable options should be “A”, “B”, “C”  
If the selected time = 3, the selectable options should be “D”, “E”, “F”  
If the selected time = 6, the selectable options should be “G”, “H”, “I”

What should I change so I can get this behaviour? Thanks!

```auto
from paraview.util.vtkAlgorithm import smproperty, smproxy
from vtkmodules.util.vtkAlgorithm import VTKPythonAlgorithmBase

@smproxy.source(label="test_time")
class Test(VTKPythonAlgorithmBase):
    def __init__ (self):
        super(). __init__ (nInputPorts=0, nOutputPorts=1)
        self.time_steps = [0.0, 3.0, 6.0]
        self.data = []
        self.data0 = ["A", "B", "C"]
        self.data3 = ["D", "E", "F"]
        self.data6 = ["G", "H", "I"]

    @smproperty.xml("""
     <StringVectorProperty information_only="1" 
                           name="CellArrayInfo"> 
       <ArraySelectionInformationHelper attribute_name="Cell" /> 
     </StringVectorProperty> 
     <StringVectorProperty command="SetCellArrayStatus" 
                           element_types="2 0" 
                           information_property="CellArrayInfo" 
                           label="Cell Arrays" 
                           name="CellArrayStatus" 
                           number_of_elements="0" 
                           number_of_elements_per_command="2" 
                           repeat_command="1"> 
       <ArraySelectionDomain name="array_list"> 
         <RequiredProperties> 
           <Property function="ArrayList" 
                     name="CellArrayInfo" /> 
         </RequiredProperties> 
       </ArraySelectionDomain> 
       <Documentation>This property lists which cell-centered arrays to 
       read.</Documentation> 
     </StringVectorProperty> 
    """)
    def SetCellArrayStatus(self, array, status):
        if status == 1:
            print(f"selected array {array}")

    def GetNumberOfCellArrays(self):
        return len(self.data)

    def GetCellArrayName(self, idx) -> str:
        return self.data[idx]

    def GetCellArrayStatus(self, *args):
        return 1

    @smproperty.doublevector(
        name="TimestepValues", information_only="1", si_class="vtkSITimeStepsProperty"
    )
    def GetTimestepValues(self):
        return self.time_steps

    def RequestInformation(self, request, inInfo, outInfo):
        executive = self.GetExecutive()
        outInfo = outInfo.GetInformationObject(0)

        outInfo.Remove(executive.TIME_STEPS())
        outInfo.Remove(executive.TIME_RANGE())

        outInfo.Set(executive.TIME_STEPS(), self.time_steps, len(self.time_steps))
        outInfo.Set(
            executive.TIME_RANGE(), [self.time_steps[0], self.time_steps[-1]], 2
        )
        return 1

    def RequestData(self, request, inInfo, outInfo):
        executive = self.GetExecutive()
        info = outInfo.GetInformationObject(0)
        time_step = info.Get(executive.UPDATE_TIME_STEP())
        print(f"Selected timestep: {time_step}")

        if time_step == 0:
            self.data = self.data0
        elif time_step == 3:
            self.data = self.data3
        else:
            self.data = self.data6
        return 1

```