Summary:
Setting `textContentType` will provide the keyboard and system with semantic meaning for inputs. Should enable password/username autofill in apps running on iOS 11+ as demonstrated here: https://developer.apple.com/videos/play/wwdc2017/206/
Also gives you the ability to disable autofill by setting `textContentType="none"`: https://stackoverflow.com/questions/48489479/react-native-disable-password-autofill-option-on-ios-keyboard
Adding `textContentType` equal to `username` or `password` should give you an autofill-bar over the keyboard which will let you fill in values from the device Keychain:
![image](https://user-images.githubusercontent.com/4932625/37848513-b2170490-2ed4-11e8-85bf-895823d4f98a.png)
Setting the appropriate `textContentType` will fill in the correct value in the `TextInput`.
I have only been able to get this to work on device, and not simulator.
Usage:
```jsx
<TextInput
value={this.state.username}
onChangeText={this.setUserName}
textContentType="username"
/>
```
```jsx
<TextInput
value={this.state.password}
onChangeText={this.setPassword}
secureTextEntry={true}
textContentType="password"
/>
```
To disable:
```jsx
<TextInput
value={this.state.password}
onChangeText={this.setPassword}
secureTextEntry={true}
textContentType="none"
/>
```
This will set `textContentType` to an empty string: https://stackoverflow.com/a/46474180/5703116
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Docs PR coming up.
[IOS] [MINOR] [TextInput] - Added `textContentType` prop for iOS 10+. Will enable password autofill for iOS 11+.
Closes https://github.com/facebook/react-native/pull/18526
Differential Revision: D7469630
Pulled By: hramos
fbshipit-source-id: 852a9749be98d477ecd82154c0a65a7c084521c1