Allow `Shell.Current.DisplayPromptAsync` to be cancelled with a `CancellationTokenSource`

Description

I have a usecase, where a prompt is displayed and an input is required. If the input doesn’t happen in a specified time, the prompt should close and return null.

Public API Changes

await Shell.Current.DisplayPromptAsync(
"Input Unit",
"Waiting for robo to input the Unit.", x,x,x,
new CancellationTokenSource(TimeSpan.FromSeconds(30))
)

Intended Use-Case

When a CancellationTokenSource is passed, and it’s cancled (by timeout or whatever), the prompt should be closed and return null or an empty string.

[AndreasReitberger]

@rachelkang From what I can see, this should work. However I haven’t tested yet. I’ll do so tomorrow and close the issue if the suggestion works as intended 😃

Thank you @pictos

[pictos]

@AndreasReitberger you can use the new extension method called .WaitAsync, that should work.

await Shell.Current.DisplayPromptAsync("f", "f").WaitAsync(new CancellationTokenSource(TimeSpan.FromSeconds(30)).Token);