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angulartypescriptangular12angular-ngselect

Angular - Select dropdown list is blank


In my Angular-12, I have this JSON response from the API endpoint:

{
  "message": "vehicle Model Detail.",
  "error": false,
  "code": 200,
  "results": {
    "vehiclemakes": [{
        "name": "Freightliner",
        "id": 15
      },
      {
        "name": "Honda",
        "id": 13
      },
      {
        "name": "Renault",
        "id": 3
      },
      {
        "name": "Suzuki",
        "id": 16
      },
      {
        "name": "Toyota",
        "id": 4,
      },
      {
        "name": "Volkswagen",
        "id": 6
      },
      {
        "name": "Volvo",
        "id": 5
      }
    ]
  }
}

Service:

public getParameters(): Observable<any> {
  return this.http.get(this.api.baseURL + 'parameters', this.httpOptions);
}

Component:

vehicles!: any[];

loadAllVehicles() {
  this.vehiclemodelService.getParameters().subscribe(
    data => {
      this.vehicles = data.results.vehicles;
    },
    error => {
      this.store.dispatch(loadErrorMessagesSuccess(error));
    }
  );
}

ngOnInit(): void {
  this.loadAllVehicles();
}

I am to load this in a dropdown select list:

HTML:

<ng-select [items]="vehicles"
   [selectOnTab]="true"
   [searchable]="true"
   bindValue="name"
   bindLabel="make_id"
   placeholder="Select Vehicle Make"
   [multiple]="false"
   [clearable]="true"
   required
   formControlName="make_id">
</ng-select>

When I loaded the form and click on the select dropdown list, it appears that data is there but it displays nothing.

How do I get this sorted out?

Thanks


Solution

  • Issues

    1. As @Nenad mentioned, results.vehicles is not valid in your JSON. You have to use results.vehiclemakes.

    2. make_id is not valid in the object of vehiclemakes. Meanwhile, bindLabel property is used to display the label, while bindValue is used for value. With existing code, the generated options will display id as label with the name as value.

    <ng-select bindValue="name"
         bindLabel="make_id">
    </ng-select>
    

    Solution

    1. Assign vehicles with data.results.vehiclemakes.
    2. Set bindLabel with name and bindValue with id.

    .component.ts

    loadAllVehicles() {
      this.vehiclemodelService.getParameters().subscribe(
        data => {
          this.vehicles = data.results.vehiclemakes;
        },
        error => {
          this.store.dispatch(loadErrorMessagesSuccess(error));
        }
      );
    }
    

    .component.html

    <ng-select [items]="vehicles"
         [selectOnTab]="true"
         [searchable]="true"
         bindValue="id"
         bindLabel="name"
         placeholder="Select Vehicle Make"
         [multiple]="false"
         [clearable]="true"
         required
         formControlName="make_id">
    </ng-select>
    

    Sample Solution on StackBlitz