Troubleshooting

Troubleshooting

The react-native ecosystem is young and moves fast. As a result, it's easy to run into issues. This page is intended to collect common problems and useful solutions.

Problem: cluttered ios-log

Looking at my iOS simulator log using react-native log-ios, there are many warning and error messages. For example:

Jul 30 13:04:36 Computer assertiond[44995] <Error>: assertion failed: 15F34 13E230: assertiond + 15801 [3C808658-78EC-3950-A264-79A64E0E463B]: 0x1
Jul 30 13:04:36 Computer Unknown[44995] <Error>:

Solution

As far as I can tell, these messages are expected to occur in the iOS simulator and harmless. There's no known way to hide these (useless) warnings.

Problem: console.error "Reload websocket error"

This red screen means that the ClojureScript code cannot create a connection to the "Boot Reload" websocket.

Solution

The error can occur in a number of different situations:

• boot dev (which opens the reload websocket) is not running

• There's a network problem that prevents the app to reach port 8079 on localhost.

  This often happens on Android because the Android emulator uses an emulated network device. In this case, the solution is to run adb reverse tcp:8079 tcp:8079 after the emulator has started.

• There's a problem with previous JavaScript code. In this case it can be helpful to inspect the app log for earlier error messages.