# Displaying only first tier of child blocks in ExtractBlock-like filter plugin

**URL:** https://discourse.paraview.org/t/displaying-only-first-tier-of-child-blocks-in-extractblock-like-filter-plugin/7844
**Category:** ParaView Support
**Created:** [August 20, 2021, 2:35pm UTC](https://discourse.paraview.org/t/displaying-only-first-tier-of-child-blocks-in-extractblock-like-filter-plugin/7844 "2021-08-20T14:35:30Z")
**Posts on this page:** 1
**Showing post:** 2

<div class="post-metadata">

### Author: ![pavel](https://discourse.paraview.org/user_avatar/discourse.paraview.org/pavel/32/8287_2.png) [@pavel](https://discourse.paraview.org/u/pavel)
#### Post date: [December 30, 2021, 8:26am UTC](https://discourse.paraview.org/t/displaying-only-first-tier-of-child-blocks-in-extractblock-like-filter-plugin/7844/2 "2021-12-30T08:26:47Z")

</div>

Hi Cailen,

If I understood correctly, you always need to display only the names from the first level of hierarchy. In this case, it is possible to simplify the task. You can try to use vtkDataArraySelection object, where you load names (“Solid”, …). It is supported directly by decorator in Python plugin:

```auto
# Ability for users to choose blocks in GUI from multi-block dataset    
    @smproperty.dataarrayselection(name="Blocks")
    def GetDataArraySelection(self):
        return self._get_array_selection()

```

, so you will be able to see it’s GUI similarly to this:

![vtkDataArraySelection_GUI_example](https://discourse.paraview.org/uploads/default/original/2X/a/a384d6e6564b4ec706341574c15b786dc66350bd.png)

and user will be able to check some blocks.

More details about plugin’s code for implementing vtkDataArraySelection you can find here: [Custom Threshold filter with dropdown selection - #5 by pavel](https://discourse.paraview.org/t/custom-threshold-filter-with-dropdown-selection/8440/5)

Hope, this approach is suitable for you.

Best Regards,  
Pavel

---

_[View the full topic](https://discourse.paraview.org/t/displaying-only-first-tier-of-child-blocks-in-extractblock-like-filter-plugin/7844)._