Error with CollectionView RemainingItemsThreshholdReached Command - mvvm

Question

I use Prism MVVM in my app. So here is my XAML code
IsRefreshing="{Binding IsRefreshing}"
Command="{Binding RefreshCommand}">
<CollectionView ItemsSource="{Binding Images}"
RemainingItemsThreshold="1"
RemainingItemsThresholdReachedCommand="{Binding UpdateImagesCommand}">
<CollectionView.ItemsLayout>
<GridItemsLayout Orientation="Vertical"
Span="3"/>
</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>
<DataTemplate>
<Grid Padding="2">
<Grid.RowDefinitions>
<RowDefinition/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<ff:CachedImage
Grid.Row="0"
Grid.Column="0"
HorizontalOptions="Center"
VerticalOptions="Center"
Aspect="AspectFill"
Source="{Binding Source, Mode=OneWay}">
<ff:CachedImage.Transformations>
<ffTransformations:CropTransformation />
</ff:CachedImage.Transformations>
</ff:CachedImage>
</Grid>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
</RefreshView>
As you can see here I have parameter RemainingItemsThreshold with the value "1", and binding anUpdateImagesCommand to the RemainingItemsThresholdReachedCommand
Here is a part of a code in view model of this xaml page
private ObservableCollection _images;
public ObservableCollection Images
{
get { return _images; }
set { SetProperty(ref _images, value); }
}
private DelegateCommand _refreshCommand;
public DelegateCommand RefreshCommand =>
_refreshCommand ?? (_refreshCommand = new DelegateCommand(ExecuteRefreshCommand));
private DelegateCommand _updateImagesCommand;
public DelegateCommand UpdateImagesCommand =>
_updateImagesCommand ?? (_updateImagesCommand = new DelegateCommand(ExecuteUpdateImagesCommand));
void ExecuteUpdateImagesCommand()
{
//Image im = new Image();
//im.Source = "Huayra3.jpg";
//Image im7 = new Image();
//im7.Source = "Huayra1.jpg";
//Images.Add(im7);
//Images.Add(im7);
//Images.Add(im);
//Images.Add(im);
//Images.Add(im);
//Images.Add(im);
}
void ExecuteRefreshCommand()
{
// refresh posts feed command
IsRefreshing = false;
}
public AccountPageViewModel(INavigationService navigationService, IUserDataService userDataService) :
base(navigationService)
{
_userDataService = userDataService;
CurrentUser = userDataService.CurrentUser;
if (String.IsNullOrEmpty(this.CurrentUser.ImagePath))
{
this.CurrentUser.ImagePath = "user_avatar.jpg";
}
Images = new ObservableCollection<Image>();
Image im = new Image();
im.Source = "Huayra3.jpg";
Images.Add(im);
Image im1 = new Image();
im1.Source = "Huayra1.jpg";
Images.Add(im1);
Image im2 = new Image();
im2.Source = "Huayra4.jpg";
Images.Add(im2);
Image im3 = new Image();
im3.Source = "Huayra3.jpg";
Images.Add(im3);
Image im4 = new Image();
im4.Source = "Huayra1.jpg";
Images.Add(im4);
Image im5 = new Image();
im5.Source = "Huayra4.jpg";
Images.Add(im5);
Image im6 = new Image();
im6.Source = "Huayra3.jpg";
Images.Add(im6);
Image im7 = new Image();
im7.Source = "Huayra1.jpg";
Images.Add(im7);
Images.Add(im7);
Images.Add(im7);
Images.Add(im7);
Images.Add(im7);
Images.Add(im7);
Images.Add(im7);
Images.Add(im);
//Images.Add(im);
//Images.Add(im);
}
As you can see I in my VIewModel constructor I've written some values and add it to list. I read microsoft documentation about CollectionView and I know that the UpdateImagesCommand will execute only when the RemainingItemsThreshold is reached. But ExecuteUpdateImagesCommand() invokes when I navigate to this page, when I navigating between my pages in my tabbed page randomly. This should not be, but I do not know the reason why this happens. Can smbd help me please?

Answer 1

I've found another way to fix this problem. I can use the IsActive PRISM property to undertand that this page is that I need.