How call Dialog from FormFlow

Question

How to call dialog in the middle of Form? I would like to call Location dialog https://github.com/Microsoft/BotBuilder-Location to get address. Thanks.

[Serializable]
public class IssueShares
{
    [Prompt("Please enter holder name:")]
    public string HolderName;
    [Prompt("Please enter holder address:")]
   **[Call(typeof(AddressDialog))]**
    public Address Address;

    [Prompt("Enter shares class:")]
    public string SharesClass { get; set; }
    [Prompt("How many shares your issue?")]
    [Describe("Number of shares")]
    public int NumberOfShares { get; set; }
}

[Serializable]
public class AddressDialog : IDialog<Address>
{
    public Task StartAsync(IDialogContext context)
    {
        context.Wait(MessageReceived);
        return Task.CompletedTask;
    }

    private async Task MessageReceived(IDialogContext context, IAwaitable<object> result)
    {
        // some logic
        context.Done(address);
    }
}

Answer 1

Are you expecting a solution based on an attribute declaration or is regular code acceptable?

Microsoft offers Dialog Chaining invoked as a sequence or a stack.

The accepted answer in the follow SO question answers your question I think.

Calling Forms from Dialogs

Here is the code extract from that answer:

var myform = new FormDialog<CreateNewLeadForm>(new CreateNewLeadForm(), CreateNewLeadForm.BuildForm, FormOptions.PromptInStart, null);

context.Call<CreateNewLeadForm>(myform, FormCompleteCallback);

Another SO question discusses the subject in more general:

Handling multiple dialogs in Microsoft bot framework