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Summary:
Follow up to 9ec9567390
Closes https://github.com/facebook/react-native/pull/16759
Differential Revision: D6285219
Pulled By: hramos
fbshipit-source-id: 7012d257a5a6cff06cb2d94203a9379e4b7e3c4e
3.1 KiB
3.1 KiB
id, title, layout, category, permalink, next, previous
| id | title | layout | category | permalink | next | previous |
|---|---|---|---|---|---|---|
| accessibilityinfo | AccessibilityInfo | docs | APIs | docs/accessibilityinfo.html | actionsheetios | webview |
Sometimes it's useful to know whether or not the device has a screen reader that is currently active. The
AccessibilityInfo API is designed for this purpose. You can use it to query the current state of the
screen reader as well as to register to be notified when the state of the screen reader changes.
Here's a small example illustrating how to use AccessibilityInfo:
class ScreenReaderStatusExample extends React.Component {
state = {
screenReaderEnabled: false,
}
componentDidMount() {
AccessibilityInfo.addEventListener(
'change',
this._handleScreenReaderToggled
);
AccessibilityInfo.fetch().done((isEnabled) => {
this.setState({
screenReaderEnabled: isEnabled
});
});
}
componentWillUnmount() {
AccessibilityInfo.removeEventListener(
'change',
this._handleScreenReaderToggled
);
}
_handleScreenReaderToggled = (isEnabled) => {
this.setState({
screenReaderEnabled: isEnabled,
});
}
render() {
return (
<View>
<Text>
The screen reader is {this.state.screenReaderEnabled ? 'enabled' : 'disabled'}.
</Text>
</View>
);
}
}
Methods
Reference
Methods
fetch()
AccessibilityInfo.fetch()
Query whether a screen reader is currently enabled. Returns a promise which
resolves to a boolean. The result is true when a screen reader is enabled
and false otherwise.
addEventListener()
AccessibilityInfo.addEventListener(eventName, handler)
Add an event handler. Supported events:
change: Fires when the state of the screen reader changes. The argument to the event handler is a boolean. The boolean istruewhen a screen reader is enabled andfalseotherwise.announcementFinished: iOS-only event. Fires when the screen reader has finished making an announcement. The argument to the event handler is a dictionary with these keys:announcement: The string announced by the screen reader.success: A boolean indicating whether the announcement was successfully made.
setAccessibilityFocus()
AccessibilityInfo.setAccessibilityFocus(reactTag)
iOS-Only. Set accessibility focus to a react component.
announceForAccessibility()
AccessibilityInfo.announceForAccessibility(announcement)
iOS-Only. Post a string to be announced by the screen reader.
removeEventListener()
AccessibilityInfo.removeEventListener(eventName, handler)
Remove an event handler.