I have found a mismatch between play in editor and mobile preview / device.
Create an UMG widget (parent). This widget creates other UMG widgets (childs).
The childs widgets intend to communicate with the parent widget using a Call to event dispatcher which the parent exposes and binds to a custom event.
This works flawless in Play in Editor / New editor window. But fails in mobile preview editor. I can see this in the log:
[2014.11.10-21.11.12:985]LogBlueprint:Error: [compiler] Error Could not find an event-dispatcher named "InventoryItemClickedDispatcher" in 'Inventory_C'.
Make sure 'Inventory_C' has been compiled for Call InventoryItemClickedDispatcher
Please let me know if you have your BP’s set up any differently then mine currently are. I have been testing on the currently release 4.5.1 and later build of the engine and have been able to play on mobile preview with no issues.
I have had many issues with UMG widgets and finally I have setup all my event handlers to being housed in a separate BP (a persistent actor BP injected on those widgets which need to communicate). However I will try to setup a fail scenario this weekend and will share with you.
I’m sorry for the late answering … I haven’t had time to setup this till now. The problem occurs when you pass references between the widgets. I attach a example which do not work (using latest promoted branch engine source).
It works on Standard editor but do not work on Preview mobile (and I guess it will not work either in android device).
I have been able to setup the example but i have been unable to see any error occur within the project. Would you be able to send me and example project so that i may be able to further investigate the issue?
Thank you again for sending that test project over. I was able to see the issue occurring very easily. I have gone ahead and written bug report UE-5799 and placed it into our bug database so that it may be addressed in a future release.
Just wanted to keep everyone updated. We do have a fix in for the 4.6.1 hotfix to fix multiple issues with the EventNode dispatchers. I am unsure as to when this will be released, but the fix has been implemented.
If you do not see a fix for this issue on that hotfix, please be sure to let me know so that i may further investigate.
Since this feature has been implemented into the 4.6.1 hotfix already, it should be in the promoted branch. You may encounter issues with the promoted branch, though, as it is an unstable build. The 4.6.1 hotfix should be released sooner rather then later, but I am unsure of an exact time at this moment.