I am struggling with grasping the concept of async angular http client. In my Java backend, I have endpoints that return data in the same format but with different meanings. To handle this, I created the following code:
export class AppComponent implements OnInit{
temperatureDailyCharts: Chart[] = new Array();
constructor(private weatherService: WeatherService){}
ngOnInit(): void {
this.getDailyParameterCharts("temperature", this.temperatureDailyCharts);
}
getDailyParameterCharts(parameter: string, chartList: Chart[]) {
this.weatherService.getDailyParameter(1, parameter)
.subscribe(response => chartList = response);
}
}
The next step involves injecting this.temperatureDailyCharts[0] into a child component and waiting for ngOnChange. However, this code is not functioning correctly as the ngOnChanges method will never be invoked. If I modify the subscribe part to explicitly assign the value like this:
.subscribe(response => this.temperatureDailyCharts = response);
then it works fine. Can someone please explain why this seemingly similar construction is causing issues?