(index):52 Uncaught ReferenceError: "Function name" is not defined at HTMLButtonElement.onclick

problem i am trying to call a function on click in my HTML button
and i got an error
P.S My TS code is in a seperated file called something.ts

share your code here please

i ve got an updated problem.How can i Get token value from one page to another?from one function to another?
how can i make it public???
//@ src/pages/home.ts//

var webApihost=“http://192.168.0.6:81/EBSWebApi/”;
var scrollerid = “ES00BACKUP/KHCApp_Items”;
var scrid = “ES00BACKUP/KHCApp_Contacts”;
var commandid = “”;
var ScrollerDatasetTest = “”;
let token;

@Component({
selector: ‘page-home’,
templateUrl: ‘home.html’
})
export class HomePage {
url: string;
params: {
SubscriptionPassword: string;
model: {
BranchID: string;
LangID: string;
UserID: string;
Password: string;
}
};

//scroller code below//
paramsScroller: {
headers: {
Authorization: string;
},
data: {
Code: string;
}
};
// Model:string;

constructor(public navCtrl: NavController,
private loginserviceprovider: LoginserviceProvider,
private storage:Storage) {

}

ionViewWillEnter() {

this.url = webApihost + 'api/login';

this.params = {
  SubscriptionPassword: 'passx',
  model: {
    BranchID: "01",
    LangID: "el-GR",
    UserID: "khcadmin",
    Password: "P@ssw0rd",
  }
};

console.log("Token prin" + token);
return this.loginserviceprovider.getWebApi(this.url, this.params)
  .subscribe(data => {
    console.log(data);
    token = data.Model.WebApiToken;
    console.log("Μόλις πήρα το Token -> " + token);
    this.navCtrl.push(LoginScreenPage);
  });

};

//@ src/pages/login-screen/login-screen.ts

var webApihost=“http://192.168.0.6:81/EBSWebApi/”;
var scrollerid = “ES00BACKUP/KHCApp_Items”;
var scrid = “ES00BACKUP/KHCApp_Contacts”;
var commandid = “”;
var ScrollerDatasetTest = “”;
var token="";

@IonicPage()
@Component({
selector: ‘page-login-screen’,
templateUrl: ‘login-screen.html’,
})
export class LoginScreenPage {
url: string;
params: {
SubscriptionPassword: string;
model: {
BranchID: string;
LangID: string;
UserID: string;
Password: string;
}
};
// public token: string;

//scroller code below//
paramsScroller: {
headers: {
Authorization: string;
},
data: {
Code: string;
Mobile1:string;
}
};
constructor(public navCtrl: NavController, public navParams: NavParams,
private loginserviceprovider: LoginserviceProvider) {
}
scrollerid(token){

console.log("ti token exw??? "+token);
this.url = webApihost + "api/rpc/SimpleScrollerRootTable/" + scrollerid;
this.paramsScroller = {
  headers: {
    Authorization: 'Bearer ' + token
  },
  data: {
    Code: "1*",
    Mobile1:""
  },
};
console.log("Πέρασε το Token μέσα στο scrollerid -> " + token);

return this.loginserviceprovider.getScrollerID(this.url, this.paramsScroller)
  .subscribe(Scroller => {
    console.log(Scroller);

  });

}