/// <summary>
/// Handles an executing async service request by showing a loading overlay until it completes execution.
/// </summary>
/// <param name="loadingOverlay">A overlay to display over the screen during the async operation.</param>
/// <param name="progress">An optional object to provide progress for the operation the overlay represents.</param>
/// <param name="executingRequest">The task for an executing request.</param>
/// <param name="onSuccess">Gets invoked if the request has completed successfully.</param>
/// <param name="onFailed">Gets invoked if the request failed, by default a standard alert message will be shown.</param>
protected async void OnAsyncServiceRequest <TResponse>(
ILoadingOverlay loadingOverlay,
IProgress progress,
Task <ServiceResult <TResponse> > executingRequest,
Action <TResponse> onSuccess,
Action <ServiceResult> onFailed)
{
Throw.IfArgumentNull(loadingOverlay, nameof(loadingOverlay));
Throw.IfArgumentNull(executingRequest, nameof(executingRequest));
Throw.IfArgumentNull(onSuccess, nameof(onSuccess));
Throw.IfArgumentNull(onFailed, nameof(onFailed));
ServiceResult <TResponse> serviceResult;
if (executingRequest.IsCompleted)
{
serviceResult = executingRequest.Result;
}
else
{
using (loadingOverlay.ShowLoadingOverlay(progress))
{
serviceResult = await executingRequest;
}
}
if (serviceResult.ResultCode == ServiceResultCode.Success)
{
onSuccess(serviceResult.Response);
}
else
{
onFailed(serviceResult);
}
}
/// <summary>
/// Wraps the background loading task to show a loading overlay until it has completed.
/// </summary>
/// <param name="loadingOverlay">A loading over overlay to display.</param>
/// <returns>A task representing the background loading.</returns>
public async Task AwaitBackgroundLoading(ILoadingOverlay loadingOverlay)
{
using (loadingOverlay.ShowLoadingOverlay())
{
await this.LoadingFromServiceTask;
}
}
/// <summary>
/// Performs an async refresh of the table by pulling updated information from a service and reloading the data in the current table.
/// </summary>
/// <param name="loadingOverlay">An optional loading overlay to display while refreshing the table.</param>
/// <returns>The refresh task.</returns>
protected async Task RefreshTable(ILoadingOverlay loadingOverlay)
{
using (loadingOverlay.ShowLoadingOverlay())
{
await this.tableSource.RefreshItemsAsync(this.ReloadTable);
}
}