Update view - Reactive Extensions

Question

I've got following code:

Observable.Interval(TimeSpan.FromMilliseconds(2500)).SubscribeOn(XXX).ObserveOn(YYY).Subscribe( t => SendCounter(t), e => HandleException(e));

Where XXX, YYY are Schedulers.

Inside SendCounter(t) I set a text with t value.

The problem is that when I run the code I got this error:

'only the original thread that created a view hierarchy can touch its views'

I'm using this component: https://components.xamarin.com/view/rxforxamarin

Possible duplicate of [error: Only the original thread that created a view hierarchy can touch its views in xamarin](http://stackoverflow.com/questions/21162096/error-only-the-original-thread-that-created-a-view-hierarchy-can-touch-its-view) — SushiHangover, Jul 02 '16 at 12:17
not too sure how to Use ObserveOn() and SubcribeOn() myself in xamarin. tried Scheduler.NewThread but thats deprecated? — filthy_wizard, Oct 18 '16 at 13:59

score 2 · Accepted Answer · answered Jul 02 '16 at 14:26

2

var uiThread = SynchronizationContext.Current;

Observable
    .Interval(TimeSpan.FromMilliseconds(2500))
    .SubscribeOn(XXX)
    .ObserveOn(uiThread)
    .Subscribe( t => SendCounter(t), e => HandleException(e));

answered Jul 02 '16 at 14:26

xleon

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This is what i needed! – Marcin Bortel Jul 02 '16 at 16:47
what do I subscribe on? how do i use this scheduler? – filthy_wizard Oct 18 '16 at 14:01
http://stackoverflow.com/questions/7579237/whats-the-difference-between-subscribeon-and-observeon – xleon Oct 23 '16 at 11:21

score 1 · Answer 2 · answered Jul 02 '16 at 12:07

1

Make sure that you Observe on the main thread so that you can affect the view directly.

answered Jul 02 '16 at 12:07

Hassan Semiu Ayomon

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score 0 · Answer 3 · answered Aug 24 '17 at 06:55

0

If you're using ReactiveUI use your code like this for e.g:

searchButton
.SelectMany(async x => await executeSearch(x))
.ObserveOn(RxApp.MainThreadScheduler)
.ToProperty(this, x => x.SearchResults, out searchResults);

ReactiveUI handbook

answered Aug 24 '17 at 06:55

Pellet

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Update view - Reactive Extensions

3 Answers3