Develop Reference

Can't set focus on first item of ListBox

I can't set focus on first item of my ListBox. ListBox has some collection bound. It looks like, that first everything in code-behind doing its stuff then there is control initializing so I would have always -1 as SelectedIndex.
XAML
<Window x:Class="Labels.Szablony"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:Labels"
mc:Ignorable="d"
Title="Labels" Height="350" Width="250" WindowStartupLocation="CenterScreen"
ResizeMode="CanMinimize" KeyDown="Window_KeyDown" Background="#FFF6A300" >
<Window.DataContext>
<local:LabelGridViewModel/>
</Window.DataContext>
<ScrollViewer VerticalScrollBarVisibility="Hidden" VerticalContentAlignment="Center"
VerticalAlignment="Center" Background="#FFF6A300">
<Grid Background="#FFF6A300" Name="labelGrid">
<ListBox x:Name="SzablonyBox" ItemsSource="{Binding LabelsCollection, IsAsync=True}"
HorizontalAlignment="Center" VerticalAlignment="Top"
MinWidth="100" MinHeight="100" BorderBrush="{x:Null}"
Background="{x:Null}" TextSearch.Text="BLABLAB"
TextSearch.TextPath="Name" IsTextSearchEnabled="True"
VerticalContentAlignment="Center" Margin="0 25 0 0"
Width="250" HorizontalContentAlignment="Center">
<ListBox.ItemContainerStyle>
<Style TargetType="{x:Type ListBoxItem}">
<EventSetter Event="PreviewKeyDown"
Handler="ListBoxItem_PreviewKeyDown"/>
</Style>
</ListBox.ItemContainerStyle>
<ListBox.ItemTemplate>
<DataTemplate>
<DockPanel Width="214">
<TextBlock Text="{Binding Name}"
FontSize="12" Height="35"
VerticalAlignment="Center"
HorizontalAlignment="Center"
Width="250"
TextAlignment="Center"/>
</DockPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<TextBox x:Name="InputText"
Text="{Binding Path=Filter, UpdateSourceTrigger=PropertyChanged}"
HorizontalAlignment="Center" Height="22" TextWrapping="Wrap"
VerticalAlignment="Top" Width="250" Background="#FFF6A300"
IsEnabled="False" BorderBrush="#FFF6A300"
VerticalContentAlignment="Center"
HorizontalContentAlignment="Center"
Foreground="Black" SelectionBrush="{x:Null}"/>
</Grid>
</ScrollViewer>
What i'm trying to do looks like:
public Labels()
{
InitializeComponent();
LabelsBox.Focus();
LabelsBox.SelectedIndex = 0;
var item = LabelsBox.ItemContainerGenerator.ContainerFromIndex(0) as ListBoxItem;
item.Focus();
}
Of course there is an exception, because item is null. Like I said SelectedIndex is always -1. What am I doing wrong ?

The ItemsSource Binding is asynchronous, so there are certainly not yet any items available while the constructor is running.
Change the Binding to be synchronous, i.e. the default behavior:
<ListBox ItemsSource="{Binding LabelsCollection}" ...>
You may also execute your initialization code as late as possible, by moving it to a Loaded event handler:
public Labels()
{
InitializeComponent();
...
Loaded += (s, e) =>
{
var item = (ListBoxItem)LabelsBox.ItemContainerGenerator.ContainerFromIndex(0);
item?.Focus();
};
}

Updating TabControl ItemSource ViewModels when specific state changes

I have a TabControl bound to an ObservableCollection property of view models, TabViewModelsCollection.
When another property gets set from within the view models, DeviceState, I'd like to raise a property changed event and tell my TabControls ItemSource to refresh.
The problem is my ItemSource is an ObservableCollection of ViewModels and when I call RaisePropertyChanged("TabViewModelsCollection"); nothing gets updated.
Furthermore my tab views contain multiple user controls and bindings.
The scenario that is supposed to play out is: A device is located on the network, data is collected, and the tabs of device information should then be updated.
Currently my TabControl only updates when I select a different device then select the device whos information I want to see. Think left panel list of devices, right panel with tabs of device info.
Let me know what part of the code you guys might want to see, my codebase is quite large so it would be hard to post it.
Here is where the TabControl is defined in my view:
<!-- Devist List Controls -->
<Grid DockPanel.Dock="Left" Margin="5,5">
<local:DeviceListView DataContext="{Binding DeviceListViewModel}" Grid.Row="0"/>
</Grid>
<GroupBox Header="Device Information" DockPanel.Dock="Right" Margin="0,0,5,5">
<TabControl IsSynchronizedWithCurrentItem="True" ItemsSource="{Binding DeviceListViewModel.SelectedDevice.TabViewModelsCollection}" SelectedItem="{Binding DeviceListViewModel.SelectedDevice.SelectedTabItemVm}" >
<TabControl.Resources>
<DataTemplate DataType="{x:Type vms:HomeViewModel}">
<local:HomeTab/>
</DataTemplate>
<DataTemplate DataType="{x:Type vms:ConfigurationViewModel}">
<Grid>
<local:ConfigurationFileView Visibility="{Binding Configuration, TargetNullValue=Collapsed, FallbackValue=Visible}"/>
<local:ErrorTab Visibility="{Binding Path= Configuration, TargetNullValue=Visible, FallbackValue=Hidden}"/>
</Grid>
</DataTemplate>
<DataTemplate DataType="{x:Type vms:ExpansionModulesViewModelFactory}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="35"/>
</Grid.RowDefinitions>
<StackPanel Grid.Row="0">
<DockPanel >
<local:ExpansionModulesList Title="Discovered/Enumerated"
DataContext="{Binding DiscoveredModules}"
/>
<GridSplitter Width="5"/>
<local:ExpansionModulesList Title="User Action Required"
DataContext="{Binding FaultyModules}"
/>
</DockPanel>
</StackPanel>
<DockPanel Grid.Row="1">
<StackPanel Orientation="Horizontal" FlowDirection="RightToLeft" Margin="5" IsEnabled="{Binding IsCommandEnabled}">
<Button Content="Cancel" HorizontalAlignment="Right"
Command="{Binding CancelExpansionCommand }"
ToolTip="Revert all local modifications by refreshing data from the controller." />
<Separator Width="10"/>
<Button Content="Apply" HorizontalAlignment="Center"
Command="{Binding ApplyExpansionCommand }"
ToolTip="Apply all changes to the controller." />
<Separator/>
</StackPanel>
</DockPanel>
</Grid>
</DataTemplate>
<DataTemplate DataType="{x:Type vms:LogViewModel}">
<local:LogView />
</DataTemplate>
<DataTemplate DataType="{x:Type vms:SignalStrengthViewModel}">
<local:SignalStrengthView />
</DataTemplate>
</TabControl.Resources>
<TabControl.ItemContainerStyle>
<Style TargetType="{x:Type TabItem}">
<Setter Property="Header" Value="{Binding Name}" />
<Setter Property="IsEnabled" Value="{Binding IsEnabled}" />
<Setter Property="Header" Value="{Binding Name}" />
</Style>
</TabControl.ItemContainerStyle>
EDIT: I want to be able to call raised property changed on this and have it refresh all of my tab views..
<TabControl IsSynchronizedWithCurrentItem="True" ItemsSource="{Binding DeviceListViewModel.SelectedDevice.TabViewModelsCollection}" SelectedItem="{Binding DeviceListViewModel.SelectedDevice.SelectedTabItemVm}" >
RaisePropertyChanged("TabViewModelsCollection");

Hi please try the next solution:
VM code redaction
private State _deviceState;
private ObservableCollection<object> _tabViewModelsCollection;
public State DeviceState
{
get { return _deviceState; }
set
{
_deviceState = value;
RaisePropertyChanged("DeviceState");
UpdateTabViewModelsCollection();
}
}
public ObservableCollection<object> TabViewModelsCollection
{
get
{
return _tabViewModelsCollection ??
(_tabViewModelsCollection = new ObservableCollection<object>(GetDeviceData()));
}
}
private void UpdateTabViewModelsCollection()
{
_tabViewModelsCollection = null;
RaisePropertyChanged("TabViewModelsCollection");
}
private List<object> GetDeviceData()
{
//implement here the data collection process
throw new NotImplementedException();
}
Xaml redaction (define the UpdateSourceTrigger)
ItemsSource="{Binding DeviceListViewModel.SelectedDevice.TabViewModelsCollection, UpdateSourceTrigger=PropertyChanged}"
Let me know if it was helpful.
Regards.

Custom ListView from inside HubAppSection -- Windows Phone 8.1

I am currently building a Windows Phone Applicaation, based off of the HubAppTemplate.
The template comes with a sample .JSON data source that it uses to populate the data of each HubSection. However, I want to use a non JSON type of data as the basis of my code. Inside my C# code, I need to make a function call to my backend to get the type of data I want out of it.
I can put this data inside of my own custom list (on the C# side), but how can I make that list act as the data source for my HubSection? Any old listview/list box works perfectly. Basically, I need help wiring the C# to the XAML -- the main issue is that I cannot access my listView inside of the datatemplate by name.
Can anyone give me some pointers to get going in the right direction?
Here is some reference code to show you what I am talking about:
<HubSection x:Uid="Clubs" Header="Clubs" DataContext="{Binding Groups}" HeaderTemplate="{ThemeResource HubSectionHeaderTemplate}">
<DataTemplate>
<ListView Name="ClubsList"
IsItemClickEnabled="True"
ItemsSource="{Binding}"
ItemClick="GroupSection_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Margin="0,0,0,27.5">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</DataTemplate>
</HubSection>
The above XAML is basically pulled straight from the hubapp template. I want to be able to use my own itemssource inside of that ListView that is generated from my C# code -- however, I cannot figure out how this ItemsSource works. I also cannot access my listview by name (ClubsList).
Here is the initialization code going on up top (wasn't sure if it was important to post this or not):
<Page
x:Class="HubAppTemplate.HubPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:HubAppTemplate"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:data="using:HubAppTemplate.Data"
DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
d:DataContext="{Binding Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:SampleDataSource}}"
mc:Ignorable="d">
<Page.Resources>
<DataTemplate x:Key="HubSectionHeaderTemplate">
<TextBlock Margin="0,0,0,-9.5" Text="{Binding}"/>
</DataTemplate>
<!-- Grid-appropriate item template as seen in section 2 -->
<DataTemplate x:Key="Standard200x180TileItemTemplate">
<Grid Margin="0,0,9.5,9.5" Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="138.5" Width="138.5"/>
<TextBlock Text="{Binding Title}" VerticalAlignment="Bottom" Margin="9.5,0,0,6.5" Style="{ThemeResource BaseTextBlockStyle}"/>
</Grid>
</DataTemplate>
<DataTemplate x:Key="StandardTripleLineItemTemplate">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}" Margin="0,9.5,0,0" Grid.Column="0" HorizontalAlignment="Left">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="79" Width="79"/>
</Border>
<StackPanel Grid.Column="1" Margin="14.5,0,0,0">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}"/>
<TextBlock Text="{Binding Description}" Style="{ThemeResource ListViewItemContentTextBlockStyle}" Foreground="{ThemeResource PhoneMidBrush}" />
<TextBlock Text="{Binding Subtitle}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" />
</StackPanel>
</Grid>
</DataTemplate>
<DataTemplate x:Key="StandardDoubleLineItemTemplate">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}" Margin="0,9.5,0,0" Grid.Column="0" HorizontalAlignment="Left">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="79" Width="79"/>
</Border>
<StackPanel Grid.Column="1" Margin="14.5,0,0,0">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}"/>
<TextBlock Text="{Binding Subtitle}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}"/>
</StackPanel>
</Grid>
</DataTemplate>
</Page.Resources>
<Grid x:Name="LayoutRoot">
<Hub x:Name="Hub" x:Uid="Hub" Header="Club Alert" Background="{ThemeResource HubBackgroundImageBrush}">
It is pulling from the JSON backend, but I want to just use my own custom listview for each section. Deleting the DataSource and data template headers gives me errors, however.
Thank you so much for your help in advance!
--A total newbie

HubSection elements require their contents to be populated via a template, so you can't just remove the <DataTemplate> tags, unfortunately. However, there is a simple way to accomplish what you are trying to do, if I understand you correctly.
If you're starting with the default Hub template, you should have this function in your HubPage.xaml.cs file
private async void NavigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
// TODO: Create an appropriate data model for your problem domain to replace the sample data
var sampleDataGroups = await SampleDataSource.GetGroupsAsync();
this.DefaultViewModel["Groups"] = sampleDataGroups;
MainViewModel viewModel = DataContext as MainViewModel;
if (!viewModel.IsDataLoaded)
{
viewModel.Load();
}
}
this.DefaultViewModel is just a Dictionary, and they have loaded the sample JSON into a variable and stored this in the ["Groups"] key of the dictionary. Since the Page's DataContext is being bound to {Binding DefaultViewModel, RelativeSource={RelativeSource Self}}, the HubSection's DataContext is being bound to {Binding Groups}, and the ItemsSource of the ListView in each DataTemplate is being bound to {Binding}, each element of the loaded JSON is being used to fill the items of the ListView.
A simple solution would be to assign this.DefaultViewModel["Groups"] to the C# List you are creating from the data you load from your back end.
Something like this:
private async void NavigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
// TODO: Create an appropriate data model for your problem domain to replace the sample data
var myData = await GetListOfThingsFromBackend();
this.DefaultViewModel["Groups"] = myData;
MainViewModel viewModel = DataContext as MainViewModel;
if (!viewModel.IsDataLoaded)
{
viewModel.Load();
}
}
A better approach would probably be to separate out all ViewModel functionality to it's own class that is better suited to your needs, and then adjust the various DataContext properties throughout the XAML, but that would likely take more time. I can elaborate if needed, but the simple solution is probably enough for now.

binding combobox images - how to select saved item in combobox images

I have a Problem with the ComboBox at wpf and xaml. The ItemsSource of my combobox is a list of (CollarTypesImage).
the binding is work fine but the problem when editing data, i can't select the item of my ComboBox.. maybe its selected but the image is not view...
but when click ComboBox, i can see all itams:
http://www.ahmadabouhamdh.com/tmp_global/1.png
i used RelativeSource , nothing changed, ComboBox not selection the my saved item:
<UserControl x:Class="TailorManager.Views.OrderDetailItem"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:vm="clr-namespace:TailorManager.ViewModels"
xmlns:Converter="clr-namespace:TailorManager.Converters"
mc:Ignorable="d"
d:DesignHeight="730" d:DesignWidth="556" FlowDirection="RightToLeft" >
<UserControl.Resources>
<!--<vm:OrderDetailItemViewModel x:Key="OrderDetailItemViewModel1" />-->
<Converter:ImageConverter x:Key="ImgConverter" />
</UserControl.Resources>
<Grid >
<ScrollViewer VerticalScrollBarVisibility="Auto" >
<ItemsControl>
<StackPanel>
<GroupBox Header="تفاصيل الياقة" Margin="5,5,5,0" VerticalAlignment="Top" Height="170">
<Grid>
<ComboBox ItemsSource="{Binding Path= DataContext.ImagesCollarTypes,
RelativeSource={RelativeSource AncestorType=UserControl,AncestorLevel=1}}"
SelectedValue="{Binding Path=OrderDetailItem.CollarTypesImage,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
SelectedValuePath="{Binding Path=OrderDetailItem.CollarTypesImage}"
Margin="393,106,0,0" VerticalAlignment="Top" HorizontalAlignment="Left" Width="132" Height="38">
<ComboBox.ItemTemplate>
<DataTemplate>
<Image Width="50" Height="50" Source="{Binding Path= CollarImage,Converter={StaticResource ImgConverter} }" />
</DataTemplate>
</ComboBox.ItemTemplate >
</ComboBox>
</Grid>
</GroupBox>
<Grid/>
</StackPanel>
</ItemsControl>
</ScrollViewer>
</Grid>
</UserControl>
i added
SelectedItem="{Binding Path=OrderDetailItem.CollarTypesImage}"
and nothing changed.
i use this Control inside window has a different DataContext type,i set the value of (DataContext OrderDetailItem) from constructor of this control.
image below explain the binding is working fine:
this image when click edit to show my saved image from DB, my item not selected:
http://www.ahmadabouhamdh.com/tmp_global/2.png
here all the code:
public List<CollarTypesImage> ImagesCollarTypes
{
get
{
//ImagesCollarTypes[0].CollarImage
if (_imagesCollarTypes.Count == 0)
{
TailorManagerDBEntities db = new TailorManagerDBEntities();
_imagesCollarTypes = db.CollarTypesImages.ToList();
}
return _imagesCollarTypes;
}
set
{
_imagesCollarTypes = value;
RaisePropertyChanged(() => ImagesCollarTypes);
}
}
public partial class CollarTypesImage
{
public CollarTypesImage()
{
this.OrderDetails = new HashSet<OrderDetail>();
}
public System.Guid CollarTypeId { get; set; }
public byte[] CollarImage { get; set; }
public virtual ICollection<OrderDetail> OrderDetails { get; set; }
}
here the xaml code from window i used my control:
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:vm="clr-namespace:TailorManager.ViewModels"
xmlns:util="clr-namespace:TailorManagerLib.Business;assembly=TailorManagerLib"
xmlns:local="clr-namespace:TailorManager.Views"
x:Class="TailorManager.Views.AddOrder"
Title="AddCustomer" Height="665" Width="974" MinWidth="600" MinHeight="666" FlowDirection="RightToLeft" >
<Window.Resources>
<vm:ManageOrderDetilsViewModel x:Key="ManageOrderDetilsViewModel1" />
</Window.Resources>
<Grid DataContext="{StaticResource ManageOrderDetilsViewModel1}" x:Name="GridDataContaner">
<Grid.Background>
...
</Grid.Background>
<GroupBox Header="تفاصيل الطلب" Margin="10,160,10,0" FlowDirection="RightToLeft">
<Grid Grid.Column="0" Name="GridOrderDetails">
<Grid.ColumnDefinitions>
<ColumnDefinition Name="ColumnDefinitionListDetails" Width="183*"/>
<ColumnDefinition Name="ColumnDefinitionDetails" Width="0*"/>
</Grid.ColumnDefinitions>
<Grid Margin="0,0,0,40" >
...
</Grid>
<Grid Grid.Column="1">
<Border BorderBrush="Black" BorderThickness="2" CornerRadius="3" Margin="4" >
<Grid>
<local:OrderDetailItem x:Name="OrderDetailItemControl" VerticalAlignment="Top" />
</Grid>
</Border>
</Grid>
...
</Grid>
</GroupBox>
</Grid>
</Window>
how i set the DataContext of the Control, this inside the command in VM of my window:
OrderDetailItemViewModel OrdDetailItem = new OrderDetailItemViewModel(Ord.OrderDetailsId);
OrderDetailItemControl.DataContext = OrdDetailItem;
Please how to fix it??
UPDATE
when i change the relative source as below:
<ComboBox Name="CmbBxImgCollarTyp" ItemsSource="{Binding Path= DataContext.ImagesCollarTypes, RelativeSource={
RelativeSource AncestorType={x:Type vm:OrderDetailItemViewModel}}"
SelectedValue="{Binding Path=OrderDetailItem.CollarTypesImage, Mode=TwoWay,
UpdateSourceTrigger=PropertyChanged}" SelectedValuePath="{Binding Path= OrderDetailItem.CollarTypesImage}" Margin="393,106,0,0" VerticalAlignment="Top"
HorizontalAlignment="Left" Width="132" Height="38">
<ComboBox.ItemTemplate>
<DataTemplate>
<Image Width="50" Height="50" Source="{Binding Path=CollarImage,
Converter={StaticResource ImgConverter}}" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
the binding never work at all modes!, i change it to this way cause the datacontext of this control is an object of the viewmodel "OrderDetailItemViewModel"
What should be fix؟؟

You have an error in your RelativeSource Binding Path. You have used the type of UserControl, but the UserControl class does not have a property named ImagesCollarTypes... instead, you should use your UserControl where you defined the property... I'm assuming that class was named OrderDetailItem:
<ComboBox ItemsSource="{Binding Path= DataContext.ImagesCollarTypes, RelativeSource={
RelativeSource AncestorType={x:Type YourViewsPrefix:OrderDetailItem}}}"
SelectedValue="{Binding Path=CollarTypesImage, Mode=TwoWay,
UpdateSourceTrigger=PropertyChanged}" SelectedValuePath="{Binding Path=
CollarTypesImage}" Margin="393,106,0,0" VerticalAlignment="Top"
HorizontalAlignment="Left" Width="132" Height="38">
<ComboBox.ItemTemplate>
<DataTemplate>
<Image Width="50" Height="50" Source="{Binding Path=CollarImage,
Converter={StaticResource ImgConverter}}" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
You should have received an error in the Output Window in Visual Studio saying something like Error: property 'ImagesCollarTypes' not found on object 'UserControl' or something similar.
Disclaimer: I didn't go through all of your code because you simply have too much there, so even after you fix this error, your code may still have other errors and not work as expected.
UPDATE >>>
For this Binding to work, the following assumptions were made:
The UserControl.DataContext must have a valid instance of an object set.
The object set as the UserControl.DataContext must have a public property named ImagesCollarTypes.
The ImagesCollarTypes property must be of a type that contains a public property named CollarTypesImage.

after check the Output window, i notes this error:
System.Windows.Data Error: 4 : Cannot find source for binding with
reference 'RelativeSource FindAncestor, AncestorType='Projectname.ViewModels.ViewModel', AncestorLevel='1''. BindingExpression:Path=LookupItems; DataItem=null; target element is 'ComboBox' (Name=''); target property is 'ItemsSource' (type 'IEnumerable')
then i change the RelativeSource from AncestorType from my ViewModel to UserControl, just like this:
RelativeSource={ AncestorType={x:Type UserControl},AncestorLevel=1}}"
and now everything working fine,
Thanks for members make an effort

Get TabItem Name in UserControl

I have the following code that creates a TabControl. Each tab contains a UserControl (code is below) that displays different data (one shows Local tax info and the other show Fed/State tax info).
TabControl
<TabControl
Name="MappingTabs"
Margin="6,7,7,8" Padding="6"
Background="White" >
<TabItem
Name="LocalTaxTab"
Padding="6,1"
Header="Local">
<AdornerDecorator>
<DockPanel>
<Border Margin="7">
<GroupBox
Name="LocalTaxesGroup">
<GroupBox.Header>
<TextBlock
FontWeight="Bold"
Text="Local Taxes">
</TextBlock>
</GroupBox.Header>
<StackPanel Margin="20,8,10,0"
Orientation="Vertical">
<local:TaxCodeMappingHeader />
<!-- Note that a row is 25 high, -->
<ScrollViewer
MaxHeight="250"
>
<ItemsControl
Name="LocalTaxCodeMappingControl"
ItemTemplate="{StaticResource MappingRuleTemplate}"
BorderThickness="0"
AlternationCount="2"
IsTextSearchEnabled="False"
HorizontalContentAlignment="Stretch"
ItemsSource="{Binding TaxCodesCollection[0].CodeCollection, NotifyOnSourceUpdated=True, UpdateSourceTrigger=PropertyChanged}">
<!-- ItemsSource="{Binding Source={StaticResource sortedCodeCollection}}"> -->
</ItemsControl>
</ScrollViewer>
<local:TaxCodeMappingFooter DataContext="{Binding RelativeSource={RelativeSource AncestorType=UserControl}}"/>
</StackPanel>
</GroupBox>
</Border>
</DockPanel>
</AdornerDecorator>
</TabItem>
<TabItem
Name="FedStateTaxesTab"
Padding="6,1"
Header="Federal\State">
<AdornerDecorator>
<DockPanel>
<Border Margin="7">
<GroupBox
Name="FedStateTaxesGroup">
<GroupBox.Header>
<TextBlock
FontWeight="Bold"
Text="Federal \ State Taxes">
</TextBlock>
</GroupBox.Header>
<StackPanel Margin="20,8,10,0"
Orientation="Vertical">
<local:TaxCodeMappingHeader />
<!-- Note that a row is 25 high, -->
<ScrollViewer
MaxHeight="250"
>
<ItemsControl
Name="FedStateTaxCodeMappingControl"
ItemTemplate="{StaticResource MappingRuleTemplate}"
BorderThickness="0"
AlternationCount="2"
IsTextSearchEnabled="False"
HorizontalContentAlignment="Stretch"
ItemsSource="{Binding TaxCodesCollection[1].CodeCollection, NotifyOnSourceUpdated=True, UpdateSourceTrigger=PropertyChanged}">
<!-- ItemsSource="{Binding Source={StaticResource sortedCodeCollection}}"> -->
</ItemsControl>
</ScrollViewer>
<local:TaxCodeMappingFooter DataContext="{Binding RelativeSource={RelativeSource AncestorType=UserControl}}"/>
</StackPanel>
</GroupBox>
</Border>
</DockPanel>
</AdornerDecorator>
</TabItem>
</TabControl>
</StackPanel>
UserControl (TaxCodeMappingFooter)
<Button
Name="AddButton"
Grid.Row="0"
Grid.Column="0"
Height="20" Width="20"
Command="{Binding Path=DataContext.AddClickCommand}"
CommandParameter="(want the tab name here)"
Style="{StaticResource ImageButton}"
ToolTip="Add a rule"
local:AttachedImage.Image="{StaticResource AddImageSource}" />
The UserControl (TaxCodeMappingFooter) contains an Add button that I need to wire up via RelayCommand to the VM. I need to somehow tell the VM which tab is calling the Add command so that an item can be added to the correct collection. I thought about sending the TabName and then keying off that to know which tab the user is on.
Is my idea correct or is the a better way to do this and if it is correct how do I get the TabName value to pass it back as a CommandParameter?

If you are going to hard code your UI controls as you have done, then perhaps your simplest option is to define a string DependencyProperty in your TaxCodeMappingFooter control:
public static readonly DependencyProperty TabNameProperty = DependencyProperty.
Register("TabName", typeof(string), typeof(TaxCodeMappingFooter));
public string TabName
{
get { return (string)GetTabName(TabNameProperty); }
set { SetTabName(TabNameProperty, value); }
}
Then you could set it from your TabItems:
<local:TaxCodeMappingFooter TabName="FedStateTaxesTab" DataContext="{Binding
RelativeSource={RelativeSource AncestorType=UserControl}}" />
And Bind to it from inside your control:
<Button Name="AddButton" Command="{Binding Path=DataContext.AddClickCommand}"
CommandParameter="{Binding TabName, RelativeSource={RelativeSource
AncestorType=TaxCodeMappingFooter}}" ... />

As others have said, if you model your view model structure appropriately, this would not be much of an issue.
If you really want to bind against an ancestor element, you can use a RelativeSource of FindAncestor, then specify the AncestorType. Note that you may need to tweak AncestorLevel if you are the descendant of more than one TabItem.
{Binding Path=Name
RelativeSource={RelativeSource Mode=FindAncestor,
AncestorType={x:Type TabItem}}}
(wrapping added for clarity)