can not get value onAsyncPress

[wangfpp]

can not get value onAsyncPress

Name | Description | Default | Type
onAsyncPress | has a callback with result of async | (value, callback) => {callback(true)} | func

my code

<Switch 
        style={style.switch}
        value={liveStatus}
         backgroundActive="#399F58"
          backgroundInactive="#33393D"
        onAsyncPress={this.onPressSet.bind(this)}
></Switch>
onPressSet(value, callback){
        console.log(value); // callback
        console.log(callback); // undefined
}