Why executeRefreshOutsideAngularZone is deprecated?

We use flag executeRefreshOutsideAngularZone and and our application is much faster

<virtual-scroller
    #scroll 
    [executeRefreshOutsideAngularZone]="true"
    (vsChange)="cd.detectChanges()"
>...
</virtual-scroller>

Why is this property obsolete?

[speige]

I’ve been thinking a lot about this & I’ve decided to keep executeRefreshOutsideAngularZone as an officially supported API.

My initial fear with executeRefreshOutsideAngularZone was because I thought it caused major bugs across my entire app. I didn’t want to deal with tech support if other developers started using the flag. However I recently realized it was actually a bug in my own manual change detection & executeRefreshOutsideAngularZone was not the root cause.

I still believe OnPush is the ideal approach, but it’s also much harder to implement. Although executeRefreshOutsideAngularZone “easier” to implement, I don’t want developers to make the same mistakes with manual change detection that I did. For this reason, I’ve added an explanation to the ReadMe which explains how to do it properly. Hopefully this will minimize any issues related to executeRefreshOutsideAngularZone.

I think executeRefreshOutsideAngularZone is a good initial approach for users to get a quick performance boost before they’re ready to move to full-appp OnPush. Thanks for submitting the initial idea & PR & thanks for helping me to understand it. Sorry I was slow/stubborn 😃

[nickbullock]

Local branch change detection is cheaper than AppRef.tick even if all of your components have OnPush strategy. I think it is Angular/NgZone code overhead. They failed to make the change detection mechanism from the root of the tree as fast as in React.js. It is still like $scope.digest() vs $rootScope.digest(). This is the only reason this flag is useful.