I want to remove an item from flipview when the user change pages. Is there anything I can do?

Question

My requirement is that i have use a flipview in my application and add pages dynamically.i want to do that when i click on addpages button my current page remove from flipview and new page comes . my code for addpage

   public void Add_Pages_Click(object sender, RoutedEventArgs e)
    {
        try
        {

            my_canvas = new Canvas();
            my_canvas.Name = "Item" + DateTime.Now.ToFileTime().ToString();
            //fp1.ItemsSource = fi;
            fp1.Items.Add(my_canvas);
            fp1.SelectionChanged += Fp1_SelectionChanged;
            Stickers1.Visibility = Visibility.Collapsed;
            Backgrounds1.Visibility = Visibility.Collapsed;
            Popup_wordart.IsOpen = false;
            PopUp_Media.IsOpen = false;
            my_canvas.Visibility = Visibility.Collapsed;
            Audio_Recorder.IsOpen = false;
        }
        catch (Exception ex)
        {


        }
       // Backward_Arrow.Visibility = Visibility.Visible;
    }

Answer 1

A very convenoent way to do this work is to build a structure in the DataTemplate for each item of the FlipView and then just use ObservableCollection to add, remove, refresh the items of the FlipView.

<FlipView x:Name="flipView" ItemsSource="{x:Bind flipviewCollection}">
    <FlipView.ItemTemplate>
        <DataTemplate>
            <Canvas>
                <Image Source="{Binding ImageSource}" Stretch="None"/>
            </Canvas>
        </DataTemplate>
    </FlipView.ItemTemplate>
</FlipView>

Define a model for the data you need to bind in the DataTemplate:

public class ImageSourceClass
{
    public string ImageSource { get; set; }
}

Then in the code behind of your FlipView, create a collection of this data model and add data to this collection:

ObservableCollection<ImageSourceClass> flipviewCollection = new ObservableCollection<ImageSourceClass>();

protected override void OnNavigatedTo(NavigationEventArgs e)
{
    flipviewCollection.Clear();
    flipviewCollection.Add(new ImageSourceClass { ImageSource = "Assets/1.jpg" });
    flipviewCollection.Add(new ImageSourceClass { ImageSource = "Assets/2.jpg" });
    flipviewCollection.Add(new ImageSourceClass { ImageSource = "Assets/3.jpg" });
    flipviewCollection.Add(new ImageSourceClass { ImageSource = "Assets/4.jpg" });
    flipviewCollection.Add(new ImageSourceClass { ImageSource = "Assets/5.jpg" });
}

At last if you want to remove an item and add a new one in the Button click event:

private void Button_Click(object sender, RoutedEventArgs e)
{
    //index = flipView.SelectedIndex + 1 because when remove one item, next item will be shown, 
    //it will behavior like a new item replace the old one.
    flipviewCollection.Insert(flipView.SelectedIndex + 1, new ImageSourceClass { ImageSource = "Assets/new.jpg" });
    flipviewCollection.Remove(flipView.SelectedItem as ImageSourceClass);                                
}

Problem is, if you didn't use this method to build a FlipView, you just added items to FlipView manually, you need also manully remove one like in your code just for example here:

private void Button_Click(object sender, RoutedEventArgs e)
{
    var my_canvas = new Canvas();
    var textbox = new TextBox();
    my_canvas.Children.Add(textbox);
    flipView.Items.Insert(flipView.SelectedIndex + 1, my_canvas);
    flipView.Items.RemoveAt(flipView.SelectedIndex);              
}