Objective-C exception thrown. Name: NSInvalidArgumentException Reason: Could not find a storyboard named 'visit_info' in bundle NSBundle the invalid context null set to uicollectionviewflowlayout invalidatelayoutWithContext : is not an instance of type

[Ahmadmansoor]

I was searching to solve my issue (as the Title says). but I couldn't reach a good point.
by the way, this issue happens just under iOS.
after many tries, I found that CollectionView doesn't like ObservableCollection of a string like this
public ObservableCollection<string> LvSitesList { get; } = new();
so when you try to fill the list like this :
if (LvSitesList.Count > 0) LvSitesList.Clear(); for (int i = 0; i < sitesList.Rows.Count; i++) { string temp = sitesList.Rows[i]["SiteName"].ToString(); temp = sitesList.Rows[i]["SiteName"].ToString() + ";" + sitesList.Rows[i]["IDSite"].ToString(); LvSitesList.Add(temp); // here the problem appear }
`
<CollectionView.ItemTemplate>





<HorizontalStackLayout
Spacing="55"

                     HorizontalOptions="Center">
                     <Label Text="{Binding TimeIn}"
                            FontSize="13"
                            FontAttributes="Bold"
                            />
                     <Label Text="{Binding TimeOut}"
                            FontSize="13"
                            FontAttributes="Bold"
                             />
                 </HorizontalStackLayout>
             </VerticalStackLayout>
         </Border>
     </DataTemplate>
 </CollectionView.ItemTemplate>

`

so to not make this too long, the answer to solve this issue is to define a list of strings like this :
public List<string> LvSitesList { get; } = new();
That's all, I like to share this just in case someone faces the same problem.