App crashes in a webinar if the host asks a panelist to start video

Hi, @Carson_Chen!

We’ve encountered a following issue which can be reproduced on MobileRTCSample

Steps to reproduce:

  • Setup a webinar meeting
  • Launch the MobileRTCSample. Go to the Settings -> Meetings Settings. Turn on “Disable Driving Mode” switch
  • Join the webinar meeting as an attendee
  • The host of the webinar promotes you to the panelists and asks to start video
  • The MobileRTCSample crashes

Notes:

  • With the enabled “Driving Mode” the app working fine and we use it as workaround for now

Environment:

  • Zoom iOS SDK v4.6.21666.0428
  • Xcode 11.3.1
  • iOS 13.5.1

Crash stack trace:
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 Foundation 0x00000001a5a8ae2c _NSKVONotifyingOriginalClassForIsa + 0
1 Foundation 0x00000001a5a8994c NSKVOClass + 36
2 UIKitCore 0x00000001a9c44788 -[UIView+ 15615880 (UIKitManual) actionForLayer:forKey:] + 176
3 QuartzCore 0x00000001ac1d07ac -[CALayer actionForKey:] + 156
4 QuartzCore 0x00000001ac1d6674 CA::Layer::begin_change+ 1390196 (CA::Transaction*, unsigned int, objc_object*, objc_object*&) + 216
5 QuartzCore 0x00000001ac1ded10 CA::Layer::set_bounds+ 1424656 (CA::Rect const&, bool) + 308
6 QuartzCore 0x00000001ac1cebbc -[CALayer setBounds:] + 112
7 UIKitCore 0x00000001a9c2128c -[UIView+ 15471244 (Geometry) setBounds:] + 536
8 UIKitCore 0x00000001a9bb2f24 -[UIScrollView setBounds:] + 984
9 UIKitCore 0x00000001a996c8b4 -[UITableView setBounds:] + 220
10 UIKitCore 0x00000001a9bb41bc -[UIScrollView setContentOffset:] + 768
11 UIKitCore 0x00000001a996d8f8 -[UITableView setContentOffset:] + 276
12 Foundation 0x00000001a5a900d4 -[NSObject+ 1028308 (NSKeyValueObservingPrivate) _changeValueForKeys:count:maybeOldValuesDict:maybeNewValuesDict:usingBlock:] + 564
13 Foundation 0x00000001a59e0774 -[NSObject+ 309108 (NSKeyValueObservingPrivate) _changeValueForKey:key:key:usingBlock:] + 68
14 Foundation 0x00000001a5a8c300 _NSSetPointValueAndNotify + 300
15 Foundation 0x00000001a5a8e6ac NSKeyValueNotifyObserver + 288
16 Foundation 0x00000001a5a90688 NSKeyValueDidChange + 336
17 Foundation 0x00000001a5a90110 -[NSObject+ 1028368 (NSKeyValueObservingPrivate) _changeValueForKeys:count:maybeOldValuesDict:maybeNewValuesDict:usingBlock:] + 624
18 Foundation 0x00000001a59e0774 -[NSObject+ 309108 (NSKeyValueObservingPrivate) _changeValueForKey:key:key:usingBlock:] + 68
19 Foundation 0x00000001a5a8c300 _NSSetPointValueAndNotify + 300
20 UIKitCore 0x00000001a9bd2668 -[UIScrollView _adjustContentOffsetIfNecessary] + 60
21 UIKitCore 0x00000001a995f16c -[UITableView _restoreOrAdjustContentOffsetWithRowCount:initialContentInsetTop:] + 480
22 UIKitCore 0x00000001a994e9e8 -[UITableView _updateVisibleCellsNow:] + 3436
23 UIKitCore 0x00000001a994ea14 -[UITableView _updateVisibleCellsNow:] + 3480
24 UIKitCore 0x00000001a994ea14 -[UITableView _updateVisibleCellsNow:] + 3480
25 UIKitCore 0x00000001a994ea14 -[UITableView _updateVisibleCellsNow:] + 3480


510 UIKitCore 0x00000001a994ea14 -[UITableView _updateVisibleCellsNow:] + 3480

@Carson_Chen

Did you have a chance to review this issue?

Hi @cocavo,

Thanks for the post and pardon the late response. This sounds very similar to one of the issues we will fix in the upcoming release. Based on the crash stack trace, it seems like MobileRTC is not mentioned, could you provide the full crash log so that we could further investigate?

Thanks!