Nativescript-ui-feedback: Error when trying to bind data on my radlistview

[dgmaar]

Please, provide the details below:

Did you verify this is a real problem

Yes

Tell us about the problem

this issue appears when trying to set data on one of my radlistview, I'm using two radlistview on my page.

* Assertion failure in -[TKCollectionView _endItemAnimationsWithInvalidationContext:tentativelyForReordering:animator:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3600.7.47/UICollectionView.m:5781
Aug 19 13:37:04 dulces-iMac com.apple.CoreSimulator.SimDevice.CA5F5C9C-1B9F-4AC1-90E5-D25E7DD049A1.launchd_sim[6335] (UIKitApplication:mx.sicar.sicarapp[0x6a03][6357][10508]): Service exited due to Segmentation fault: 11

Which platform(s) does your issue occur on?

iOS

Please provide the following version numbers that your issue occurs with:

nativescript │ 3.1.3 │ 3.1.3
tns-core-modules │ 3.1.1 │ 3.1.1
tns-android │ 3.1.1 │ 3.1.1
tns-ios │ 3.1.0 │ 3.1.0

[ginev]

@dgmaar - to be able to better assist we would need some more information about the way you are fetching your data and assigning it to RadListView. Can you please share some source here?

[tsonevn]

closing due to inactivity

[felixkrautschuk]

@tsonevn @ginev I get exactly this error message on iOS, you can have a look at the following sample project:

AssertionFailure.zip

Steps to reproduce:

1. tap the button to navigate to the list-page

2. wait until data is loaded (on iOS it takes a while until the items are loaded, see here

3. navigate back

4. tap the button and navigate to the list page again.

Note: when I put the clear-functionality of the observable-array into a timeout, the error does not occur, even with 0 ms timeout. But I don't know if this may have side effects, that's why I don't do tit this way.

[tsonevn]

Hi @felix-idf,
Thank you for the sample project.
I tested it on my side, however, the application was build successfully and the binding works as expected after secondary navigation.

Can you check if you are using the latest version of NativeScript CLI 3.4.2? Also, try removing the platform with tns platform remove android and delete node_modules folder. Then rebuild the app tns run android.

[felixkrautschuk]

Hi @tsonevn ,
thank you for your fast reply.

As @dgmaar already mentioned in this thread, the problem is the iOS platform, not Android (everything works as expected there).

I have NativeScript 3.4.3 installed and I tested this with the iOS simulator: iPhone 6 - iOS 10.3.1.

The following GIF shows steps 3 and 4 of the described scenario until the app crashes:

* Assertion failure in -[TKCollectionView _endItemAnimationsWithInvalidationContext:tentativelyForReordering:animator:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3600.7.47/UICollectionView.m:5569

[felixkrautschuk]

Thanks for re-opening this issue.

I noticed, that the sample app, the databinding is done a different way:

The viewmodel is is a class that extends the Observable class and you assign a new instance of this ViewModel class as the bindingContext of the page each time in the navigatingTo event of the page.
This way, the error does not occur on iOS...

Apart from the fact, that it would be a huge amount of work to re-write the Viewmodel machanism for all pages in our app, I think it is not resource-friendly to create a new instance of the ViewModel class everytime you navigate to a page, instead of re-using an existing object.

I hope there is another way to overcome this issue.

[anuragd7]

Hi, Iam facing a similar issue in my nativescript angular project too. The rad list view loads fine, but when I try to delete an item from the list view it fails with the error - * Assertion failure in -[TKCollectionView _endItemAnimationsWithInvalidationContext:tentativelyForReordering:animator:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3600.9.1/UICollectionView.m:5569.

Any fixes/ solutions would be highly appreciated.

[shivgolani]

Hello @fakalieva replacing navigatingTo with loaded resolves the bug.