mirror of
https://github.com/zhigang1992/react-native.git
synced 2026-02-02 09:08:58 +08:00
Summary:
While adeveloper requests the emitter to emit an event, the emitter
may not emit the event immediately instead of putting the request
into a queue and process it later.
This diff allows the developer to provide a callback which will be called
when the event has been emitted.
For instance:
```
class NavigationContext {
push(nextRoute) {
var nextStack = this._stack.push(nextRoute);
this.emit(
'change',
{
reason: 'push',
nextStack: nextStack,
nextRoute: nextRoute,
},
this._onPush
);
}
_onPush(event){
if (event.defaultPrevented) {
return;
}
this._stack = event.nextStack;
this.emit('change');
}
}
```