As discussed in a previous ticket you've opened regarding RadListView, there seems to be a bug in the native iOS UICollectionView that causes issues in certain cases:
There are several suggestions for effective workarounds and we are going to evaluate them before committing to any fixes. For the time being, here is a slightly updated code snippet from your app that addresses the erroneous behaviour:
// self.set("countries1", new observableArrayModule.ObservableArray());
// self.set("countries2", new observableArrayModule.ObservableArray());
list = response.content.toJSON().RestResponse.result;
I am sorry for the inconvenience caused.
Let me know in case of further questions.
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