when you want to store some small ,insensitive and permanent information in your app

1. npm install react-native-user-defaults
2. open xcode, right click on Libraries, then click Add Files..., select node_modules -> react-native-user-defaults -> RCTUserDefaults.xcodeproj
3. still in xcode, select main project file, then Build Phases -> Link Binary... -> Add items -> libRCTUserDefaults.a

If you are not clear about the step 2 and 3, you can check react-native official doc , follow the step 1 and 2 in the official doc.

In objective-c and swift, you have to use specific method for specific type, like setObject and stringForKey. But in react-native, I believe that all you need is just set and get.

Every method supports callback and promise

import userDefaults from 'react-native-user-defaults'

set({String}, {String, Number, Bool, Object, Array}, [,suiteName] [,callback])

Example:
userDefaults.set("key1", "valueIsString")
 .then(data => console.log(data))   // Save success

userDefaults.set("key2", [1, true], "group.com.company.app", (err, data) => {
 if(!err) console.log(data)         // Save success
})

get({String} [,suiteName] [,callback])

Example:
userDefaults.get("key1")
 .then(data => console.log(data))   // value for the key1

userDefaults.get("key2", "group.com.company.app", (err, data) => {
 if(!err) console.log(data)         // value for the key2
})

remove({String} [,suiteName] [,callback])

Example:
userDefaults.remove("key1")
 .then(data => console.log(data))   // Remove success

empty([suiteName] [,callback])

Example:
userDefaults.empty()
 .then(data => console.log(data))   // Empty success

1. No tests? I have tested all methods, I promise. I've checked other famous react-native components, they all don't have tests, I think we are all seeking a way of formal tests.
2. Why not swift? I wrote this in swift at the beginning, but I find it's hard for others and even myself to integrate it into an existed project.
3. Type bug? if you set('key1', '12'), then get('key1'), you will get 12, not '12', I don't take this as a bug so that we can use this component more conveniently. If you don't think so, tell me.

MIT