CODEWITHSUNDEEP
xamarin.formsprism
wogi
wogi

Reputation: 1

OnNavigatedTo vs Initialize(Async)

I am having a hard time to understand when to use Initialize and when to use OnNavigatedTo.

I understand that Initialize is execute once when the view model is initialized and OnNavigatedTo is executed every time I navigate to the page.

What is the best way on deciding what to do in Initialize and what to do in OnNavigatedTo?

Especially in a situation where I have data passed by navigation parameters but also fetched from additional apis (some even with http calls that can take a while)

Thanks a lot

Upvotes: 0

Views: 452

Answers (1)

yguerin
yguerin

Reputation: 266

Using Initialize will be triggered only when your ViewModel is created meaning you will have to destroy it and recreated it before triggering this method again.

OnNavigatedTo will be triggered every time your page (the one linked to this ViewModel) will appears, meaning it will be the case on the first navigation (same as Initialized) but also every time you will go back to this page.

So if you have the following navigation pattern: Page 1 > Page 2 > Go back to Page 1, Initialized will be triggered only on step 1 (creation of your ViewModel) while OnNavigatedTo will be triggered twice, once in step 1 and the other time on step 3.

Upvotes: 1

Related Questions