# Is it possible to display simple black text in the "Output Messages" window?

**URL:** https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243
**Category:** ParaView Support
**Created:** [October 14, 2025, 1:07pm UTC](https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243 "2025-10-14T13:07:11Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![CsatiZoltan](https://discourse.paraview.org/user_avatar/discourse.paraview.org/csatizoltan/32/6997_2.png) [@CsatiZoltan](https://discourse.paraview.org/u/CsatiZoltan)
#### Post date: [October 14, 2025, 1:07pm UTC](https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243/1 "2025-10-14T13:07:11Z")

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Hi,

I use `vtkWarningMacro` in my C++ plugin to display complementary messages in the _Output Messages_ window. While this is useful for debugging purposes, for informative messages I would prefer text in black and without the traceback info. Is it possible in ParaView?

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### Author: ![nicolas.vuaille](https://discourse.paraview.org/user_avatar/discourse.paraview.org/nicolas.vuaille/32/5873_2.png) [@nicolas.vuaille](https://discourse.paraview.org/u/nicolas.vuaille)
#### Post date: [October 21, 2025, 7:20am UTC](https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243/2 "2025-10-21T07:20:08Z")

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Hi,  
you may look at the `vtkOutputWindow` singleton then.

Actually the text will be green and not black, but this is the standard informative text in the _Output Messages_

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### Author: ![CsatiZoltan](https://discourse.paraview.org/user_avatar/discourse.paraview.org/csatizoltan/32/6997_2.png) [@CsatiZoltan](https://discourse.paraview.org/u/CsatiZoltan)
#### Post date: [October 21, 2025, 7:55am UTC](https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243/3 "2025-10-21T07:55:00Z")

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Thank you, but it only prints to the terminal:

```cpp
vtkNew<vtkOutputWindow> w;
w->DisplayErrorText("-----------------------------------------"); // same for DisplayDebugText

```

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### Author: ![nicolas.vuaille](https://discourse.paraview.org/user_avatar/discourse.paraview.org/nicolas.vuaille/32/5873_2.png) [@nicolas.vuaille](https://discourse.paraview.org/u/nicolas.vuaille)
#### Post date: [October 22, 2025, 2:24pm UTC](https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243/4 "2025-10-22T14:24:31Z")

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Yes, that is why I mentioned the _singleton_. You can get it with `auto w = vtkOutputWindow::GetInstance()` instead of creating your own.

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### Author: ![CsatiZoltan](https://discourse.paraview.org/user_avatar/discourse.paraview.org/csatizoltan/32/6997_2.png) [@CsatiZoltan](https://discourse.paraview.org/u/CsatiZoltan)
#### Post date: [October 22, 2025, 2:31pm UTC](https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243/5 "2025-10-22T14:31:04Z")

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Thanks, it works perfectly! How do I know when to use singleton objects?

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### Author: ![nicolas.vuaille](https://discourse.paraview.org/user_avatar/discourse.paraview.org/nicolas.vuaille/32/5873_2.png) [@nicolas.vuaille](https://discourse.paraview.org/u/nicolas.vuaille)
#### Post date: [October 23, 2025, 3:28pm UTC](https://discourse.paraview.org/t/is-it-possible-to-display-simple-black-text-in-the-output-messages-window/17243/6 "2025-10-23T15:28:22Z")

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Hopefully some class documentation mentions that. Otherwise, when a static method named `GetInstance` or similar exists, it often means that the class is intended to be used following the singleton pattern.