Binding a ListView selected item to a user control

Question

I have a Page which contains a ListView of users :

<ListView ItemsSource="{Binding UserList}"
          SelectedItem="{Binding SelectedUser}">
    <GridView>
        <GridViewColumn DisplayMemberBinding="{Binding Id}" />
        <GridViewColumn DisplayMemberBinding="{Binding Name}"/>
    </GridVie>
</ListView>

I have also a user control which will display all the data of the selected user from that ListView. So I binded the SelectedUser to a dependency property CurrentUser of UserUc

<userControls:UserUc CurrentUser="{Binding SelectedUser}" />

The user control does not display the data ! Why ?

Edit

I added this to the code behind of the page :

public static readonly DependencyProperty SelectedUserProperty = WpfDpHelper.Register<UserListUc, User>(i => i.SelectedUser, Callback);

private static void Callback(UserListUc userListUc, DependencyPropertyChangedEventArgs<User> DependencyPropertyChangedEventArgs)
{
    Debug.WriteLine("user selection changed");
}

And when I change the selection of any user the setter gets fired

Second edit : The user control

<UserControl ...
             DataContext="{Binding RelativeSource={RelativeSource Self}}">
    <ListView ItemsSource="{Binding CurrentUser.CommentList}">
        <!-- I want to show the user comments -->
    </ListView>
</UserControl>

Code behind

public static readonly DependencyProperty CurrentUserProperty = WpfDpHelper.Register<UserUc, User>(i => i.CurrentUser);
public User CurrentUser
{
    get { return (User) GetValue(CurrentUserProperty); }
    set { SetValue(CurrentUserProperty, value); }
}

did you look in VS output window for some binding exceptions ? — Tigran, Dec 06 '13 at 13:57
Does SelectedUser's setter fire PropertyChanged? Can you please post a part of UserUc codebehind related to dependency property in question? — Somedust, Dec 06 '13 at 13:58
Does SelectedUser get set by the ListView? I think you need a two-way binding — Flat Eric, Dec 06 '13 at 13:59
@FlatEric SelectedItem binds two-way by default. http://msdn.microsoft.com/ru-ru/library/system.windows.controls.primitives.selector.selecteditem(v=vs.110).aspx — Somedust, Dec 06 '13 at 14:02
I tried before TwoWay, OneWay, OneWayToSource. Non of them worked — Wassim AZIRAR, Dec 06 '13 at 14:03
show your usercontrol code and hopefully you have set the datacontext right there :) i think the problem is your DP binding within your usercontrol — blindmeis, Dec 06 '13 at 14:11
@KingKing Yes I did checked that. DataContext="{Binding RelativeSource={RelativeSource Self}}" — Wassim AZIRAR, Dec 06 '13 at 14:11
Try making it a regular public property with a get, set, and notifypropertychanged. — paparazzo, Dec 06 '13 at 14:16
I see you posted more code. Implement iNotifyPropertyChanged. — paparazzo, Dec 06 '13 at 14:20
I'm using DependencyProperties instead of implementing INotifiyPropertyChanged — Wassim AZIRAR, Dec 06 '13 at 14:22
But DependencyProperties is not working so what is it going to hurt to go with NotifyPropertyChanged? — paparazzo, Dec 06 '13 at 14:27
@Blam No it's working I use the all the time, I'm just (maybe) missing something because I use DataContext in both of them. So at runtime it doesn't recongnize which one to pick — Wassim AZIRAR, Dec 06 '13 at 14:29
pls check my answer. you simply dont have to set the datacontext to self within a usercontrol — blindmeis, Dec 06 '13 at 14:29

blindmeis · Accepted Answer · 2013-12-06T14:23:18.830

1

if you set the datacontext in your usercontrol to self - thats wrong. pls use ElementName Binding. So all you have to do is to remove your DataContext="{Binding RelativeSource={RelativeSource Self}}"

 <UserControl x:Name="uc">
   <ListView ItemsSource="{Binding ElementName=uc,CurrentUser.CommentList}">
    <!-- I want to show the user comments -->
   </ListView>

edited Dec 06 '13 at 14:23

answered Dec 06 '13 at 14:14

blindmeis

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You were right sir. I had to remove the DataContrext in the User control. But I don't understand why I can't use the DataContext in both of them ? – Wassim AZIRAR Dec 06 '13 at 14:30
1

check the comments from H.B. here: http://stackoverflow.com/questions/11226843/data-binding-in-wpf-user-controls thats a good explanation :) – blindmeis Dec 06 '13 at 14:33

Binding a ListView selected item to a user control

1 Answers1