问题
I'm trying to create a dialog in which I define multiple waterfall steps. In the context of this dialog, I need sometimes to go back to the previous waterfall step according to the choice of the user. I found this method :
await stepContext.ReplaceDialogAsync("Name of the dialog");
however, this method re-execute the whole dialog and this is not what I need.
In fact, the waterfall steps that I created are three :
- ChoiceCallStepAsync: The first step will list the first 10 calls of the user with the options to show older steps
- ShowCallStepAsync: The second step will show the call that the user choose or go back to the first step if the user clicked on "show older"
- EndDialog: The third step will terminate the dialog
My code is :
public class ListAllCallsDialog : ComponentDialog
{
// Dialog IDs
private const string ProfileDialog = "ListAllCallsDialog";
/// <summary>
/// Initializes a new instance of the <see cref="ListAllCallsDialog"/> class.
/// </summary>
/// <param name="loggerFactory">The <see cref="ILoggerFactory"/> that enables logging and tracing.</param>
public ListAllCallsDialog(ILoggerFactory loggerFactory)
: base(nameof(ListAllCallsDialog))
{
// Add control flow dialogs
var waterfallSteps = new WaterfallStep[]
{
ListAllCallsDialogSteps.ChoiceCallStepAsync,
ListAllCallsDialogSteps.ShowCallStepAsync,
ListAllCallsDialogSteps.EndDialog,
};
AddDialog(new WaterfallDialog(ProfileDialog, waterfallSteps));
AddDialog(new ChoicePrompt("cardPrompt"));
}
/// <summary>
/// Contains the waterfall dialog steps for the main dialog.
/// </summary>
private static class ListAllCallsDialogSteps
{
static int callListDepth = 0;
static List<string> Calls;
public static async Task<DialogTurnResult> ChoiceCallStepAsync(WaterfallStepContext stepContext, CancellationToken cancellationToken)
{
await stepContext.Context.SendActivityAsync(
"Right now i'm in list all calls dialog",
cancellationToken: cancellationToken);
GetAllCalls();
return await stepContext.PromptAsync("cardPrompt", GenerateOptions(stepContext.Context.Activity, callListDepth), cancellationToken);
}
public static async Task<DialogTurnResult> ShowCallStepAsync(WaterfallStepContext stepContext, CancellationToken cancellationToken)
{
// Get the text from the activity to use to show the correct card
var text = stepContext.Context.Activity.Text.ToLowerInvariant();
if(text == "Show older")
//Go back to the first step
else if(text == "Show earlier")
//Go back to the first step
else
await stepContext.Context.SendActivityAsync(
"The call you choose is : " + text.ToString(),
cancellationToken: cancellationToken);
return await stepContext.ContinueDialogAsync();
}
public static async Task<DialogTurnResult> EndDialog(WaterfallStepContext stepContext, CancellationToken cancellationToken)
{
await stepContext.Context.SendActivityAsync(
"Getting back to the parent Dialog",
cancellationToken: cancellationToken);
return await stepContext.EndDialogAsync(null, cancellationToken);
}
/// <summary>
/// Creates options for a <see cref="ChoicePrompt"/> so the user may select an option.
/// </summary>
/// <param name="activity">The message activity the bot received.</param>
/// <returns>A <see cref="PromptOptions"/> to be used in a prompt.</returns>
/// <remarks>Related type <see cref="Choice"/>.</remarks>
private static PromptOptions GenerateOptions(Activity activity, int callListDepth)
{
// Create options for the prompt
var options = new PromptOptions()
{
Prompt = activity.CreateReply("Please choose a call from the list below"),
Choices = new List<Choice>(),
};
for(int i=10*callListDepth; i <= 10 * (callListDepth + 1); i++)
{
if (Calls.ElementAtOrDefault(i) != null)
options.Choices.Add(new Choice() { Value = Calls[i] });
}
options.Choices.Add(new Choice() { Value = "Show older" });
if(callListDepth!=0)
options.Choices.Add(new Choice() { Value = "Show earlier" });
return options;
}
private static void GetAllCalls()
{
//List of all calls found
for (int i = 0; i < 30; i++)
Calls.Add("Call" + i.ToString());
}
}
}
Can someone show me how to do this, please ?
回答1:
I'm not sure, if it's the right and efficient way to do it, but you can experiment with the State property of the context.ActiveDialog within your Task<DialogTurnResult> function.
context.ActiveDialog.State["stepIndex"] = (int)context.ActiveDialog.State["stepIndex"] -2;
回答2:
Waterfall dialogs weren't designed with the idea of 'going backwards' to traverse them, though I can see the possible need to. The only solution I've found is to break your waterfall into smaller "mini" waterfalls, and nest them into one larger waterfall.
// define and add waterfall dialogs (main)
WaterfallStep[] welcomeDialogSteps = new WaterfallStep[]
{
MainDialogSteps.PresentMenuAsync,
MainDialogSteps.ProcessInputAsync,
MainDialogSteps.RepeatMenuAsync,
};
Then in MainDialogSteps.ProcessInputAsync:
public static async Task<DialogTurnResult> ProcessInputAsync(
WaterfallStepContext stepContext,
CancellationToken cancellationToken)
{
var choice = (FoundChoice)stepContext.Result;
var dialogId = Lists.WelcomeOptions[choice.Index].DialogName;
return await stepContext.BeginDialogAsync(dialogId, null, cancellationToken);
}
This allows the users to start new dialogs still within the main dialog stack. One of my options I offered was a prompt of a list of phone numbers:
WaterfallStep[] phoneChoiceDialogSteps = new WaterfallStep[]
{
PhoneChoicePromptSteps.PromptForPhoneAsync,
PhoneChoicePromptSteps.ConfirmPhoneAsync,
PhoneChoicePromptSteps.ProcessInputAsync,
};
Add(new WaterfallDialog(Dialogs.PhonePrompt, phoneChoiceDialogSteps));
And finally, in the PhoneChoicePromptSteps.ProcessInputAsync, I allowed for the selection of 'no' from the confirm to ReplaceDialogAsync and effectivly reset this smaller waterfall, without effecting the rest of the overall waterfall:
public static async Task<DialogTurnResult> ProcessInputAsync(
WaterfallStepContext stepContext,
CancellationToken cancellationToken)
{
if ((bool)stepContext.Result)
{
await stepContext.Context.SendActivityAsync(
$"Calling {stepContext.Values[Outputs.PhoneNumber]}",
cancellationToken: cancellationToken);
return await stepContext.EndDialogAsync(null, cancellationToken);
}
else
{
return await stepContext.ReplaceDialogAsync(Dialogs.PhonePrompt, null, cancellationToken);
}
}
来源：https://stackoverflow.com/questions/52554441/bot-framework-v4-0-how-to-execute-the-previous-waterfall-step-in-a-dialog