Question

I have a class with data:

public class routedata : INotifyPropertyChanged

{

    private List<double> distances;
    public List<double> Distances
    {
        get { return this.distances; }
        set
        {
            if (this.distances != value)
            {
                this.distances = value;
                this.onPropertyChanged("Distances");
            }
        }
    }

    private List<string> instructions;
    public List<string> Instructions
    {
        get { return this.instructions; }
        set
        {
            if (this.instructions != value)
            {
                this.instructions = value;
                this.onPropertyChanged("Instructions");
            }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void onPropertyChanged(string property)
    {
        if (this.PropertyChanged != null)
        {
            this.PropertyChanged(this, new PropertyChangedEventArgs(property));
        }
    }        
}

I’m trying to bind it to a listview like this:

     <GridView Name="routeView" HorizontalAlignment="Left" Height="310" Margin="1025,318,0,0" Grid.Row="1"      
           VerticalAlignment="Top" Width="340" >
            <ListView Name="routeList" Height="300" Width="330" ItemsSource="{Binding routeData}">
                <ListView.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal">
                            <TextBlock Text="{Binding Instructions}"
                                                      TextWrapping="Wrap" Width="200"/>
                            <TextBlock Text="{Binding Distances}"
                                                      Margin="10,0,0,0" />
                            <TextBlock Text="km"/>
                        </StackPanel>
                    </DataTemplate>
                </ListView.ItemTemplate>
            </ListView>
        </GridView>

I have in my c# code behind: routeList.datacontext = this;

but it is still not binding, only one empty row is populated in the listview. I have checked the data and it is all present. Any help would be appreciated thank you.

Answer 1

A ListView takes a single collection as ItemsSource, so if you want to display multiple TextBlocks for each item – you need a collection of objects with multiple text properties to bind to your DataTemplate. In your case a routeData is not a collection. Instead you need to define your item view model, e.g.

public class RoutePoint
{
    public double Distance { get; set; }
    public string Instruction { get; set; }
}

then you would bind your ListView.ItemSource to a List and in your DataTemplate bind it like that:

<TextBlock Text="{Binding Distance}"/>
<TextBlock Text="{Binding Instruction}"/>

You don’t need to use an ObservableCollection if your collection never changes after you bind it to the ListView for the first time (SelectedItem doesn’t constitute a change).