private ChoicePromptHandler CreateChoicePromptHandler()
{
if (this.activePromptHandler != null)
{
Logger.LogError(
"Prompt handler requested while another prompt is already active.");
}
ChoicePromptHandler choicePromptHandler = this.OnCreateChoicePromptHandler();
this.activePromptHandler = choicePromptHandler;
this.activePromptHandler.PromptCancelled += activePromptHandler_PromptCancelled;
return(choicePromptHandler);
}
/// <summary>
/// Prompts the user to make a choice using the provided details.
/// </summary>
/// <param name="promptCaption">
/// The caption string which will be displayed to the user.
/// </param>
/// <param name="promptMessage">
/// The descriptive message which will be displayed to the user.
/// </param>
/// <param name="choices">
/// The list of choices from which the user will select.
/// </param>
/// <param name="defaultChoice">
/// The default choice to highlight for the user.
/// </param>
/// <param name="cancellationToken">
/// A CancellationToken that can be used to cancel the prompt.
/// </param>
/// <returns>
/// A Task instance that can be monitored for completion to get
/// the user's choice.
/// </returns>
public Task <int> PromptForChoiceAsync(
string promptCaption,
string promptMessage,
ChoiceDetails[] choices,
int defaultChoice,
CancellationToken cancellationToken)
{
// TODO: Guard against multiple calls
this.Caption = promptCaption;
this.Message = promptMessage;
this.Choices = choices;
this.DefaultChoices =
defaultChoice == -1
? Array.Empty <int>()
: new int[] { defaultChoice };
// Cancel the TaskCompletionSource if the caller cancels the task
cancellationToken.Register(this.CancelPrompt, true);
// Convert the int[] result to int
return(this.WaitForTaskAsync(
this.StartPromptLoopAsync(this.promptCancellationTokenSource.Token)
.ContinueWith(
task =>
{
if (task.IsFaulted)
{
throw task.Exception;
}
else if (task.IsCanceled)
{
throw new TaskCanceledException(task);
}
return ChoicePromptHandler.GetSingleResult(task.GetAwaiter().GetResult());
})));
}