Question

I’m going to preface this by saying that I understand the new Windows 8 application lifecycle and how it is now 100% up to the user to decide if they want to terminate the app or not. So, I guess what I’m looking to find is a way to pseudo-restart my app, although I’m open to other suggestions as I’m pretty new to designing Modern UI apps.

I’m building an app that interfaces with a Web 2.0 service that requires authentication via OAuth. Fortunately the Windows 8 WebAuthenticationBroker makes this simple: it displays an asynchronous modal window that houses the web frame to allow the user to sign in and I get to provide a callback method when its done.

Now, obviously I only want to display this sign-in screen if I don’t already have a session key stored for the user in roamingSettings.values. I used the Grid App template in Visual Studio, and I execute these functions in default.js as soon as the app is activated (checking roamingStorage, calling WebAuthBroker, etc). Now, the Grid App template provides a data.js to allow me to define some of the REST endpoints that I want to fetch. The main problem is that I can’t fetch these REST endpoints until the user is authenticated! Yet they still have to (at least, I think) be declared in data.js ahead of time. So what I’m doing now to avoid errors in the event that the user isn’t signed in, is the following:

if (roamingSettings.values[sessionKey]){
   list = getFeedItems(); // my function that issues all the REST calls
} else {
   list = new WinJS.Binding.List();
}

This works fine if the app is manually restarted after authentication is complete, but I would really rather have a way of completely reloading the app asynchronously after authentication is complete. I’ve spent a ton of time on this already and I’m getting extremely annoyed because I’ve seen other apps do this (Instametrogram, for example).

Any ideas?

Answer 1

To answer the core question here, how do you soft restart: window.location.reload() is all you need. This just does the refresh in place.

However, what you are actually looking to do is reset the datasource on the ListView instance — all you need to do is get hold of that control at runtime, and re-assign the data source to it. E.g.:

var lv = document.getElementById("myListView");
lv.winControl.itemSource = list;

An example of this should also be in the app you have from when it currently assigns the list to the listview.