/// <summary>
/// Invokes a task and wrap it to busy indicator.
/// </summary>
/// <param name="task">The specified <see cref="Task" />.</param>
/// <param name="viewModel">The specified <see cref="IViewModel" />.</param>
/// <param name="message">The specified message for the <c>BusyMessage</c> property.</param>
/// <param name="handleException">
/// Responsible for handling errors if true errors will be processed using the
/// <see cref="ITaskExceptionHandler" /> interface; otherwise false
/// </param>
public static TTask WithBusyIndicator <TTask>([NotNull] this TTask task, [NotNull] IViewModel viewModel,
object message = null, bool?handleException = null)
where TTask : Task
{
Should.NotBeNull(task, "task");
Should.NotBeNull(viewModel, "viewModel");
if (handleException == null)
{
handleException = ApplicationSettings.HandleTaskExceptionBusyIndicator;
}
if (task.IsCompleted)
{
if (handleException.Value)
{
ToolkitExtensions.TryHandleTaskException(task, viewModel, viewModel.GetIocContainer(true));
}
return(task);
}
Guid beginBusy = viewModel.BeginBusy(message);
task.TryExecuteSynchronously(t =>
{
viewModel.EndBusy(beginBusy);
if (handleException.Value)
{
ToolkitExtensions.TryHandleTaskException(t, viewModel, viewModel.GetIocContainer(true));
}
});
return(task);
}
public override async Task Execute(object parameter = null)
{
try
{
_viewModel.Error = string.Empty;
try
{
await _viewModel.SetBusy();
if (BeforeExecute != null)
{
await BeforeExecute();
}
await base.Execute(parameter);
}
finally
{
await _viewModel.EndBusy();
}
if (AfterExecuteSucceeded != null)
{
await AfterExecuteSucceeded();
}
}
catch (InvalidOperationException e)
{
_viewModel.Error = e.Message;
if (AfterExecuteFailed != null)
{
await AfterExecuteFailed();
}
}
}