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Votes
0
Found in
2021.3.44f1
2022.3.52f1
6000.0.26f1
6000.1.0a2
6000.2.0a1
Issue ID
UUM-86655
Regression
No
“Drags can only be started from MouseDown or MouseDrag events” error is thrown when registering the MouseDownEvent on a BlackboardField and calling DragAndDrop.PrepareStartDrag() and DragAndDrop.StartDrag()
Reproduction steps:
1. Open the attached “BugRepro” project
2. Open the “Assets/ASSET WITH BUG.asset” asset
3. Create a new variable on the blackboard (Click + sign > MyCustomVariable)
4. Try to drag and drop the “New variable” on the graph
5. Observe the Console window
Expected result: No errors are thrown
Actual result: “Drags can only be started from MouseDown or MouseDrag events” error is thrown
Reproducible with: 2021.3.44f1, 2022.3.52f1, 6000.0.26f1, 6000.1.0a2
Reproducible on: Windows 11
Not reproducible on: No other environment tested
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Resolution Note:
We reproduced the error using the steps described in the bug report. We put a breakpoint where the error is logged, and the call stack shows that it happens during a MouseDownEvent, not a MouseDownEvent like the bug description says.
Furthermore, there is no error printed in the console at the moment that the custom variable is clicked, but only when it is moved to the drop location to be released, which confirms that the drag error is not related to the MouseDownEvent.
Hence, this logged error happening during a MouseMoveEvent is behaving as designed.