Part of the MobileRTCVideoView is black

Sometimes part of the MobileRTCVideoView screen is turned black. It looks like picture in picture mode. I suspect (for no reason) that this black rectangle may be a camera of the user. I have no idea why this black overlay is there. There are no other views that could overlay video. All that I’m doing with MobileRTCVideoView is removing and adding video units:

val renderInfo = MobileRTCVideoUnitRenderInfo(0, 0, 100, 100)
MobileRTCVideoViewManager.addAttendeeVideoUnit(userId, renderInfo)

Also I’m calling MobileRTCVideoView’s onPause and onResume functions in according Activity callbacks. There are all my interactions with the view.

Zoom SDK version: 5.0.24433.0616

Unfortunately I can’t reproduce this issue consistently.



  • Device: Galaxy Tab S3 (SM-T820)
  • OS: Android
  • Version: 8

Hi @oleh.durasov, thanks for using the devforum.

This is strange behavior and definitely should not be happening. If possible, can you try upgrading to the most recent version of our SDK? Here is a link to download it.

Also, at what point in time are you seeing this black square? Is it present immediately after the attendee video is added? Does it persist for the whole time that the attendee’s video is being rendered?

Lastly, you’ve mentioned you’re calling onPause and onResume on the view from the corresponding Acitivity lifecycle callbacks. When you see this square appear, is there any user input that would cause these to trigger?


Hi @jon.lieblich, thanks for the fast reply.

On the latest release we updated SDK to the most recent version, currently I can’t tell you if the problem persists on the latest version.

I believe, that black rectangle is seen immediately, after user joined the meeting and attendee video is started being rendered, and it persists the whole time.

As for the onPause and onResume callback, I fear that I can’t provide you with the certain information.

Hi @oleh.durasov,

Without more information, we are unable to determine with any certainty that this issue is not being caused by a defect with the camera on the device.

Please let me know if you find any new information that points towards this being a bug with the SDK.


Hi @jon.lieblich, thanks for the update.

I’ll try to do more testing and somehow reproduce this issue. As for now, thank you for pointing that it might be an issue with the camera on the device, I’ll also look into this possibility.

As soon as I get more information I’ll let you know.