Send extra param to ionic event handler

I’m using ionic native IBeacon.I want to check if my device can see a ibeacon when user clicks a button.And I want to pass data to event handler ,just like this in my code ;

> CheckinButtonClick(id,checkinTime)
>   {
>          this.nativeStorage.getItem("password").then(
>         mydata => {
>         // I want to pass mydata  to event handler "mySubscribedHandler"
>             this.events.subscribe("didRangeBeaconsInRegion", this.mySubscribedHandler );
>         }
>   }
> 
>    mySubscribedHandler:any = (data) => {
>             var isfound = false;    
>                 this.beacons = [];
>                 let beaconList = data.beacons;
>                 beaconList.forEach((beacon) => {
> // i will check if my device can see a specific beacon i found=true
>                    if(isfound)
>                    {
>                    // i will call a rest service   
>                    }  
>                 });
>         // and i will unsubscribe the event 
>  this.events.unsubscribe("didRangeBeaconsInRegion",this.mySubscribedHandler);
> 
>             }