# ComboBoxString OnChanged Event Args Crash PIE and Editor

**URL:** <https://forums.unrealengine.com/t/comboboxstring-onchanged-event-args-crash-pie-and-editor/2681462>\
**Category:** Programming & Scripting\
**Tags:** editor-crash, combobox, pie, unreal-engine, Event, bug-report, UMG\
**Created:** [December 3, 2025, 5:15am UTC](https://forums.unrealengine.com/t/comboboxstring-onchanged-event-args-crash-pie-and-editor/2681462 "2025-12-03T05:15:42Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Doctor\_Kannon](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/doctor_kannon/32/1130101_2.png) [@Doctor\_Kannon](https://forums.unrealengine.com/u/Doctor_Kannon)\
**Post date:** [December 3, 2025, 5:15am UTC](https://forums.unrealengine.com/t/comboboxstring-onchanged-event-args-crash-pie-and-editor/2681462/1 "2025-12-03T05:15:42Z")

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This is occurring again in 5.5.4

> [@On Selection Changed Combobox-String Causes Editor To Crash With No Crash Window.](https://forums.unrealengine.com/t/on-selection-changed-combobox-string-causes-editor-to-crash-with-no-crash-window/1146326/3):
>
> I don’t recall specifically how I solved it, it has been a while since I have visited this specific blueprint. However I just tested it out now and it seems to work fine. Basically I wanted the player to design their own government for their faction. They can use either the dropdown or the slider and it will change the value of the other. Here is my BP and the two macros I wrote to change either with vise versa. Hope it helps let me know if you still need help.

I have a UMG Menu with ComboBoxes. The ComboBox options are populated (Add Option) during Event Construct. The ComboBox OnChanged event was simply printing the SelectedItem arg. However, the OnChanged event was being triggered by the Add Option node, which resulted in the PIE and Editor crashing (no report window).

To try and fix this, I toggled the IsEnabled boolean, before and after Add Option. That had no effect. I then added a boolean, [ComboBoxReady] to serve in the same capacity. This solved the Add Option crash, but the crash still occurred on actual mouse-selection. This selection-crash occurred because I was still printing the event handler’s SelectedItem arg.

Finally, I quit asking the event handler for any information. If the ComboBox is ready, I call a custom event. In that custom event, I query the ComboBox. So far this works.

 ![comboBoxFixed](https://d3kjluh73b9h9o.cloudfront.net/original/4X/0/5/9/0592d6f865a6c66faac4bb994ecf3ee876d6523a.png)

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<div class="post-metadata">

**Author:** ![Doctor\_Kannon](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/doctor_kannon/32/1130101_2.png) [@Doctor\_Kannon](https://forums.unrealengine.com/u/Doctor_Kannon)\
**Post date:** [December 3, 2025, 1:02pm UTC](https://forums.unrealengine.com/t/comboboxstring-onchanged-event-args-crash-pie-and-editor/2681462/2 "2025-12-03T13:02:25Z")

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This pass-by-crash bug is not fixed. Not resolved. We have a work-around. This is a bug report and the work-around is not a solution.