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Background Fetching Indicators

A query's status === 'pending' state is sufficient enough to show the initial hard-loading state for a query, but sometimes you may want to display an additional indicator that a query is refetching in the background. To do this, queries also supply you with an isFetching boolean that you can use to show that it's in a fetching state, regardless of the state of the status variable:

angular-ts
@Component({
  selector: 'todos',
  template: `
    @if (todosQuery.isPending()) {
      Loading...
    } @else if (todosQuery.isError()) {
      An error has occurred: {{ todosQuery.error().message }}
    } @else if (todosQuery.isSuccess()) {
      @if (todosQuery.isFetching()) {
        Refreshing...
      }
      @for (todos of todosQuery.data(); track todo.id) {
        <todo [todo]="todo" />
      }
    }
  `,
})
class TodosComponent {
  todosQuery = injectQuery(() => ({
    queryKey: ['todos'],
    queryFn: fetchTodos,
  }))
}
@Component({
  selector: 'todos',
  template: `
    @if (todosQuery.isPending()) {
      Loading...
    } @else if (todosQuery.isError()) {
      An error has occurred: {{ todosQuery.error().message }}
    } @else if (todosQuery.isSuccess()) {
      @if (todosQuery.isFetching()) {
        Refreshing...
      }
      @for (todos of todosQuery.data(); track todo.id) {
        <todo [todo]="todo" />
      }
    }
  `,
})
class TodosComponent {
  todosQuery = injectQuery(() => ({
    queryKey: ['todos'],
    queryFn: fetchTodos,
  }))
}

Displaying Global Background Fetching Loading State

In addition to individual query loading states, if you would like to show a global loading indicator when any queries are fetching (including in the background), you can use the useIsFetching hook:

angular-ts
import { injectIsFetching } from '@tanstack/angular-query-experimental'

@Component({
  selector: 'global-loading-indicator',
  template: `
    @if (isFetching()) {
      <div>Queries are fetching in the background...</div>
    }
  `,
})
export class GlobalLoadingIndicatorComponent {
  isFetching = injectIsFetching()
}
import { injectIsFetching } from '@tanstack/angular-query-experimental'

@Component({
  selector: 'global-loading-indicator',
  template: `
    @if (isFetching()) {
      <div>Queries are fetching in the background...</div>
    }
  `,
})
export class GlobalLoadingIndicatorComponent {
  isFetching = injectIsFetching()
}