On Selection Changed Combobox-String Causes Editor To Crash With No Crash Window.

I have an enum file for different types of governments factions in my game can have. In the widget editor I set up a combobox string node to accept the enum, add the enum values to it as options and lets the player select them. The editor crashes with no crash report window based on a random choice if I click one option in the drop down. It is hard to pinpoint which option is causing it as I have to load back up UE to reproduce it. None of the enums have any associated blueprints that would modify any data if selected yet this is just for menu creation so far. See below blueprint. I tried doing it without the print string and it still crashes.

EDIT: So I found a crash folder in my project folder and skimmed through the 4 files in there and I don’t see anything specifically indicating it. This could be a result of my naivety since I am new to UE.

We are seeing a similar crash on a CombBox(Key). Stepping through the blueprint debugger in PIE gets to the OnSelectionChanged event, and then the next step crashes on a memcopy. This same project / asset has no crash in UE 5.0, but upgrading to 5.2 or 5.3 crashes. It still crashes even if we disconnect the execution wire coming out of the OnSelectedChanged Event node.

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.



In our case, after we dynamically populate the ComboBox at runtime, we called SetSelectedOption to select the “None” option which should always be first in the list. After noticing some weird stuff in Unreal 5.3 with ComboBoxKey (e.g. SetSelectedOption broadcasts a field value change event before updating the value, which was added after UE 5.0 - but the ComboBox OnSelectionChanged callback handler will trigger a second event broadcast) I changed to using ComboBoxString and it seemed to fix our issue.

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