3.4 KiB
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(): Promise
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: ChangeEventName, handler: Function): Object
Add an event handler. See Change Event Names.
setAccessibilityFocus()
AccessibilityInfo.setAccessibilityFocus(reactTag: number): void
Set accessibility focus to a React component.
Platform |
---|
iOS |
announceForAccessibility()
AccessibilityInfo.announceForAccessibility(announcement: string): void
Post a string to be announced by the screen reader.
Platform |
---|
iOS |
removeEventListener()
AccessibilityInfo.removeEventListener(eventName: ChangeEventName, handler)
Remove an event handler. See Change Event Names.
Change Event Names
change
Fires when the state of the screen reader changes. The argument to the event handler is a boolean. The boolean is true
when a screen reader is enabled and false
otherwise.
announcementFinished
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.
Platform |
---|
iOS |