I've start learning angular 2. I try to get some data via http get request and then I would like to build objects with that data so I can display them with template later. If I am thinking with the wrong way you can tell me.
I have my model AnalyticsData:
export class AnalyticsData {
pagePath: string;
pageViews: number;
uniquePageViews: number;
avgTimeOnPage: number;
entrances: number;
bounceRate: number;
constructor(object?: any) {
this.pagePath = object && object.pagePath || null;
this.pageViews = object && object.pageViews || null;
this.uniquePageViews = object && object.uniquePageViews || null;
this.avgTimeOnPage = object && object.avgTimeOnPage || null;
this.entrances = object && object.entrances || null;
this.bounceRate = object && object.bounceRate || null;
}
}
My DataService:
export class DataService {
private dataUrl: string = 'http://example.com/app/analyticsdata';
constructor(private http: Http) { }
getData() {
return this.http.get(this.dataUrl)
.map((response: Response) => response.json());
}
}
My AnalyticsComponent:
export class AnalyticsComponent implements OnInit {
myData: Array<AnalyticsData>;
constructor(private services: DataService) { }
ngOnInit(): void {
this.getData();
}
getData() {
this.services.getData()
.subscribe(
function (response) {
response.forEach((element: AnalyticsData, index: number) => {
this.myData.push(
new AnalyticsData({
pagePath: element['ga:pagePath'],
pageViews: element.pageViews,
uniquePageViews: element.uniquePageViews,
avgTimeOnPage: element.avgTimeOnPage,
entrances: element.entrances,
bounceRate: element.bounceRate
})
);
});
},
function (error) { console.log("Error happened" + error) },
function () {
console.log("the subscription is completed");
}
);
}
}
The error with the above is: EXCEPTION: Cannot read property 'push' of undefined
. I don't understand why this happened because I've assign the variable myData
on the top of the class.
Also use arrowFunction ()=>
as shown below,
getData() {
this.services.getData()
.subscribe(
(response) => { //<<<<===here
response.forEach((element: AnalyticsData, index: number) => {
this.myData.push(
new AnalyticsData({
pagePath: element['ga:pagePath'],
pageViews: element.pageViews,
uniquePageViews: element.uniquePageViews,
avgTimeOnPage: element.avgTimeOnPage,
entrances: element.entrances,
bounceRate: element.bounceRate
})
);
});
},
(error) => { console.log("Error happened" + error) }, //<<<===here
() => { //<<<===here
console.log("the subscription is completed");
}
);
}
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