how to use ion-toggle in notification using ionic2 - html

Question

I am doing notifications in ionic 2 i have taken one toggle button and wrote the get and post call for that one.
below is my html code.
<ion-header>
<ion-navbar>
<ion-title>Notifications</ion-title>
</ion-navbar>
</ion-header>
<ion-content padding>
<ion-item no-lines (click)="Update()">
<ion-label> Notification</ion-label>
<ion-toggle checked={{notify}} ></ion-toggle>
</ion-item>
</ion-content>
below is my ts file..
import { Component } from '#angular/core';
import { NavController } from 'ionic-angular';
import { Logger } from '../../providers/logger/logger';
import { Rest } from '../../providers/network/rest';
/*
Generated class for the Notifications page.
See http://ionicframework.com/docs/v2/components/#navigation for more info on
Ionic pages and navigation.
*/
#Component({
selector: 'page-notifications',
templateUrl: 'notifications.html'
})
export class NotificationsPage {
public noteValue;
public notify : boolean;
NotificationsArray=[];
constructor(public navCtrl: NavController,
public logger: Logger,
public rest: Rest){
}
ionViewDidLoad() {
this.rest.get('/getNotification')
.subscribe((result)=>
{
console.log("checking getNotification"+JSON.stringify(result));
//this.logger.debug(["getNotification"][0]["newsletter"]);
if(result.status == '1'){
if(result.notify == '1'){
this.notify=true;
console.log("success of getNotification");
//this.NotificationsArray=result.data;
}
else{
this.notify=false;
console.log("error of getNotification");
}
}
})
}
Update(){
let setNotificationObj = {
newsletter:this.notify
}
this.notify = !this.notify;
console.log("cheking setNotificationObj " + JSON.stringify(setNotificationObj));
this.rest.post('/setNotification',setNotificationObj)
.subscribe((result)=>
{
console.log("checking data of success " +JSON.stringify(result));
if(result.status == '1'){
}
else{
console.log("error");
}
});
}
}
my get call is working but when i am off&on the toggle button its getting json at position 0 error. please check my post call..