How to Refresh a Main Razor Page from Sub-Components After an API Call?

Refreshing the Main Razor Page from Sub-Components After an API Call

This guide addresses the challenge of updating a main Razor page from its sub-components following an API call, specifically focusing on maintaining a loading state during data retrieval. The solution leverages a scoped service and Blazor's InvokeAsync(StateHasChanged) method.

Problem: The initial search displays a loading spinner, but subsequent filter applications fail to trigger it.

Solution: This solution uses a scoped service to manage application state and coordinate updates between components.

Implementation Steps:

1. Scoped Service (AppState): Create a scoped service (e.g., AppState) to track whether API data has been received. This service will hold a boolean flag, such as API_Data_Received.

2. Sub-Component Filtering (FilterRazorComponent): When a filter is applied within a sub-component:

   • Set AppState.API_Data_Received to false, signaling the need for data refresh.
   • Navigate to the SearchResults.razor page, passing any necessary filter parameters. Consider using navigation parameters to efficiently pass data.

3. Main Page (SearchResults.razor):

   • Inject the AppState service.
   • In OnInitializedAsync(), asynchronously check AppState.API_Data_Received.
   • If AppState.API_Data_Received is false, display a loading indicator and initiate the API call.
   • Upon successful API call completion, set AppState.API_Data_Received to true and call InvokeAsync(StateHasChanged) to refresh the UI, removing the loading indicator and displaying the updated results.

This approach ensures that the main SearchResults.razor page consistently reflects the loading state and updates its content after each API call triggered by sub-component interactions. The use of a scoped service provides a clean and efficient way to manage the application state and trigger UI updates.

The above is the detailed content of How to Refresh a Main Razor Page from Sub-Components After an API Call?. For more information, please follow other related articles on the PHP Chinese website!