React Native development menu freezing in iOS emulator

Question

From yesterday I started getting this issue in iOS emulator:

When I hit cmd+D in iOS emulator to bring up development menu, App becomes unresponsive for ~30 sec. Then w

Answer 1

Looking at your video, it seems that you have enabled the Slow animations debugging mode in the iOS Simulator, perhaps by accidentally pressing Cmd + T.

Try turning off the slowed animations under the Debug > Slow Animations menu or by pressing Cmd + T again.

I am not sure of the root cause of the unresponsiveness, but it is perhaps due to the native Action Sheet component animating out on the button press before the control is returned to the application.

Answer 2

In case you are having trouble with emulators, you can at first use a physical iOS device to circumvent the issue. The react native menu does not freeze there (tested).

Periodical freezing of the screen can happen if you are using apps that use accessibility features, like e.g. BetterTouchTool or SizeUp with Xcode versions 7.0 and 7.1 and the issue should be resolved in Xcode 7.2 beta as discussed here.

If that doesn't help, try disabling Slow Animations as described in the accepted answer.