MvvmCross detecting RequestClose or back button pr

I found this topic which says that MvvmCross has no way of detecting RequestClose or use pressing a back button: WP7 MVVMCross Detect RequestClose or BackKeyPressed inside ViewModels backkeypressed-inside-viewmodels

Did anything change since May, 2012? Any reasons why this functionality isn't build into MvvmCross? I don't want to re-engineer the wheel it seems like this can be built very simply into Android, WP7, and iOS. If I don't find solution, I will end up building it.

The advice from before is still correct.

it seems like this can be built very simply into Android, WP7, and iOS

I may be wrong or missing something, but when in the past I've tried to build this, the simplicity seems to have become complicated quite quickly :(

While it may seem simple in one particular case, for a general framework there are numerous other cases to consider - e.g. when using pivots, tabs, popups, modals, split-views, etc - and in these multiple cases a standard approach may not be entirely universal.

iOS, in particular, sometimes makes this kind of detection much harder (especially in a general case where your UIViewController may or may not be inside a NavigationController).

What can be simpler is detecting and signalling the events for whether or not a view is visible - but even that doesn't seem to be entirely simple - there are cases in iOS where ViewDidDisappear will not get called - and besides, these events may simply not be what your app needs to respond to...

While it may feel like all you need is a wheel, the obvious fact is that there is no one universal wheel - wheels come in many different styles and sizes. I've now seen quite a lot of MvvmCross apps... and I've yet to work out what a standard app looks like. What's 'obviously' the right design and architecture in one app, can look totally different to the approach taken in others.

In general, I suspect that where individual apps need this kind of functionality then this will be in very well defined scenarios - e.g. with known view types inside a known presentation framework. In those cases, then I suspect implementing something just for that app scenario will be quite straight-forward for the app developer at the time. I also suspect that some of those scenarios can be shared between some apps - but I'm not sure that one code pattern will fit all - or even many.

I'm very, very happy to see users blog, github-post, or forum-talk about their experiences in this area when they write them. Blog posts like http://www.gregshackles.com/2012/11/returning-results-from-view-models-in-mvvmcross/ show how patterns can be applied and reused on top of Mvvm.

It may even be that out of such blog posts we find a way of getting more functionality inside the core mvvmcross (and other) libraries - but it's also important to me that we keep the core library as light, flexible and extensible as possible.

As people, like yourself, talk about their cross-platform mvvm experiences, I do my best to keep the links page up to date - http://slodge.blogspot.co.uk/p/mvvmcross-quicklist.html - that hopefully will help people share ideas, concepts and code.