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Viewsproblem with access object property in typescript angular
I have a typescript object like this
const playlist: { tracks: Array<Track> } = { tracks: new Array<Track>() };
And this is Track interface
interface Track {
title?: string;
album?: string;
artists?: string;
duration?: string;
explicit?: boolean;
url?: string;
}
I'm trying to get data from Spotify web API to my playlist object like this
for (let i = 1; i <= iterationCount; i++) {
const endpointX = `${BASE_API_URL}playlists/${playlistId}/tracks?limit=${PLAYLIST_ITEM_LIMIT}&offset=${i}&fields=${fieldString}`;
const subscription: Subscription = this.http.get<WritableTrackList>(endpointX).subscribe(data => {
for (const item of data.items) {
const track: Track = this.helperService.trackApiObject2TrackObject(item.track);
this.playlist.tracks.push(track);
}
});
}
When I try to print playlist object in the javascript console with console.log(this.playlist);, it's working.
Buth I try to print playlist.tracks with console.log(this.playlist.tracks);, it's print an empty array
Why can't I access the tracks property of the playlist object? How can i access this property? Any solution?
·
Juan Pablo Isaza
2 answers
Answer question0
try this :
console.log(this.playlist['tracks']);
if you want to use like this.playlist.tracks you must declare an interface for playlist:
interface PlayList{
tracks:Track[]
}
·
Juan Pablo Isaza
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0
maybe try to print it inside the subscription.
.subscribe(data => {
for (const item of data.items) {
const track: Track = this.helperService.trackApiObject2TrackObject(item.track);
this.playlist.tracks.push(track);
}
console.log([...this.playlist.tracks])
});
// printing outside subscription will most likely give an empty array
although in general you would want something reactive
tracks$ = this.http.get<WritableTrackList>(endpointX).pipe(map(trackApiObject2TrackObject));
then in the template
<ng-template ngFor let-track[ngForOf]="tracks$| async">
<app-track [track]></app-track>
</ng-template>
·
Juan Pablo Isaza
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