# UMG UComboBoxString bugs

**URL:** <https://forums.unrealengine.com/t/umg-ucomboboxstring-bugs/319651>\
**Category:** UI\
**Tags:** combobox, unreal-engine, bug-report, UI, CPP, question, UMG\
**Created:** [May 24, 2015, 8:37pm UTC](https://forums.unrealengine.com/t/umg-ucomboboxstring-bugs/319651 "2015-05-24T20:37:45Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![kamrann](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@kamrann](https://forums.unrealengine.com/u/kamrann)\
**Post date:** [May 24, 2015, 8:37pm UTC](https://forums.unrealengine.com/t/umg-ucomboboxstring-bugs/319651/1 "2015-05-24T20:37:45Z")

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I’m having a lot of issues with the reliability of UComboBoxString. The two most reproducible problems are:

1. The OnOpening delegate appears to get fired as a result of clicking on the combo box itself while its list is open, despite the fact that this action (as expected) closes the list.
2. Double clicking a closed combo box will open and close it (as expected), however in this case the OnOpening is only fired once, yet a subsequent click will fail to open the list, despite triggering OnOpening.

The above issues seem to occur with just a basic setup. I have far more serious problems when trying to use the combo box in a perhaps less standard way - I want to update the contents dynamically, by clearing/adding options either in the tick function or in response to the OnOpening event. When doing so, issues with the combo box repeatedly not opening (despite OnOpening being triggered) are very frequent.

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**Author:** ![anonymous\_user\_e729f54e](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_e729f54e](https://forums.unrealengine.com/u/anonymous_user_e729f54e)\
**Post date:** [May 26, 2015, 2:52pm UTC](https://forums.unrealengine.com/t/umg-ucomboboxstring-bugs/319651/2 "2015-05-26T14:52:50Z")

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Hello ,

I was able to reproduce these issues on our end. I have written up a report for the OnOpening event miss firing ( UE-16128), however the other issue has been resolved on an internal version of the engine and will be available in a later release. I have submitted the report to the developers for further consideration. I will provide updates with any pertinent information as it becomes available. Thank you for your information and time.

Make it a great day

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**Author:** ![kgamble](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@kgamble](https://forums.unrealengine.com/u/kgamble)\
**Post date:** [October 6, 2015, 6:09pm UTC](https://forums.unrealengine.com/t/umg-ucomboboxstring-bugs/319651/3 "2015-10-06T18:09:44Z")

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I just encountered the first issue today (using 4.9) and I’d just like to add that when this is fixed it would be nice to have an OnClosing event added that is fired when OnOpening currently is.

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**Author:** ![anonymous\_user\_e729f54e](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_e729f54e](https://forums.unrealengine.com/u/anonymous_user_e729f54e)\
**Post date:** [October 6, 2015, 6:14pm UTC](https://forums.unrealengine.com/t/umg-ucomboboxstring-bugs/319651/4 "2015-10-06T18:14:24Z")

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Hello ,

Thank you for your interest, however I will need you to create a new thread for tracking purposes. You can then place a link in a reply to this thread at which point I will be happy to assist you further.

Make it a great day