使用SemanticZoom的JumpList在Windows Phone 8.1中不起作用

Question

I followed the tutorial on this page: http://modernography.wordpress.com/2014/04/26/jumplists-in-windows-phone-8-1/

I have a collectionviewsource:

// artistdata
public CollectionViewSource ArtistList
{
    get
    {
        var data = App.musicdata.Artists;
        var groups = data.ToAlphaGroups(x => x.name);
        _ArtistList = new CollectionViewSource();
        _ArtistList.Source = groups; //groups is the result of using my extension methods above
        _ArtistList.IsSourceGrouped = true;

        return _ArtistList;
    }
}

Which I bind to my XAML:

<PivotItem x:Name="artists" Margin="10,0">
    <SemanticZoom Style="{StaticResource AlphaJumpListStyle}">
        <SemanticZoom.ZoomedInView>
            <ListView Background="Transparent" ItemsSource="{Binding ArtistList.View}" Loaded="ListviewLoaded">
                <ListView.GroupStyle>
                    <GroupStyle HeaderTemplate="{StaticResource AlphaGroupHeaderTemplate}" HeaderContainerStyle="{StaticResource JumpListListHeaderContainerStyle}" HidesIfEmpty="True" />
                </ListView.GroupStyle>
                <ListView.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Grid.Column="1" Margin="10,5" Tapped="ArtistSelected">
                            <TextBlock FontFamily="Segoe WP" FontSize="22" Foreground="White" Text="{Binding name}" HorizontalAlignment="Left" VerticalAlignment="Top" Width="{Binding ActualWidth, ElementName=parentElementName}"/>
                            <TextBlock FontFamily="Segoe WP" FontWeight="Light" FontSize="17" Foreground="#7FFFFFFF" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="0,-5,0,0">
                        <Run Text="{Binding amountofalbums}"/>
                        <Run Text="albums"/>
                            </TextBlock>
                        </StackPanel>
                    </DataTemplate>
                </ListView.ItemTemplate>
            </ListView>
        </SemanticZoom.ZoomedInView>
        <SemanticZoom.ZoomedOutView>
            <GridView ItemsSource="{Binding ArtistList.View.CollectionGroups}" Style="{StaticResource AlphaJumpListPickerStyle}" />
        </SemanticZoom.ZoomedOutView>
    </SemanticZoom>
</PivotItem>

It all displays correctly, I can open and close the JumpList. BUT, when I tap on a letter in the zoomedoutview, the zoomedinview doesn't jump to that letter. Instead, it stays where it was?

I can't find the cause for this problem. Maybe the problem is that the SementicZoom is inside a Pivot?

Answer 1

I think the issue is caused because ListView and GridView are obtaining different instances of CollectionView. As the example shows, you should cache the first created instance.

The code should be:

public CollectionViewSource ArtistList
{
    get
    {
        if(_ArtistList == null)
        {
            var data = App.musicdata.Artists;
            var groups = data.ToAlphaGroups(x => x.name);
            _ArtistList = new CollectionViewSource();
            _ArtistList.Source = groups; //groups is the result of using my extension methods above
            _ArtistList.IsSourceGrouped = true;
        }
        return _ArtistList;
    }
}