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combobox and listview binding issue wpf c#

I have a combobox which displays listview on dropdown, I am following MVVM Pattern and i have also set the public property in my Viewmodel and it works fine when i am assigning it to the Label but for Combobox it doesn't seem to rely on my binding. i tried numerous ways but unable to find the issue.
XAML :
<ComboBox Name="SearchBox" IsEditable="True" Background="White" md:HintAssist.Hint="Search MUID" Grid.Column="1" Margin="5 0 0 0"
Grid.Row="0" Height="40" Width="400" HorizontalContentAlignment="Left" HorizontalAlignment="Left" SelectedItem="{Binding ElementName=lstview ,Path=SelectedItem}" >
<ComboBoxItem>
<ListView x:Name="lstview" ItemsSource="{Binding filterSW}"
SelectedItem="{Binding SelectedMU}"
Height="200" ScrollViewer.VerticalScrollBarVisibility="Visible">
<ListView.View>
<GridView>
<GridViewColumn Width="130" Header="Mu-ID" />
<GridViewColumn Width="130" Header="MU-Identifier" DisplayMemberBinding="{Binding MU_Identifier}" />
<GridViewColumn Width="130" Header="Status" DisplayMemberBinding="{Binding RequestType}" />
<GridViewColumn Width="130" Header="UniqueID" />
</GridView>
</ListView.View>
</ListView>
</ComboBoxItem>
</ComboBox>
This works fine for me when i am using the public property and accessing its element , i also tried setting text={Binding SelectedMU.MU_Identifier} and selectedvalue but its just not working.
<Label Grid.Column="3" HorizontalAlignment="Center" Background="GreenYellow" Content="{Binding SelectedMU.MU_Identifier}"></Label>

It looks like you're trying to show a multi-column list in your ComboBox dropdown instead of the standard list where each item shows just a text line.
To achieve this effect you've placed a ListView inside the dropdown.
Unfortunately, this is just not going to work.
Both ComboBox and ListView descend from Selector which is an abstraction that allows to select an item from a list. This limits the property SelectedItem to one of the items that are contained in the list. If you try to assign to this property any value that it not in the list, the assignment is not going to work and the property will retain the value it had before you did the assignment.
Now, the list could either be specified right inside XAML or provided as a binding to property ItemsSource. You do the binding correctly for the ListView. But for the ComboBox you don't specify that binding. Instead you specify exactly one item of type ComboBoxItem which contains the whole ListBox as its value. So the only value that could be successfully assigned to the SelectedItem property of the ComboBox is that single ComboBoxItem. But your binding is never going to assign that value, that's why the ComboBox never shows anything when closed.
When it's open it does show the single item which contain the ListView but this is just an optical effect. The data binging is not going to work. The reason why it works for the Label is because the Label is not constrained and can show anything that the ListView tells it to show.
You can synchronize the ListView and the ComboBox only when both controls have the same bindings for both ItemsSource and SelectedItem properties. But in this case you won't be able to place the ListView inside the dropdown.
The closest you can get to what you want is by customizing the ComboBox's template as described in https://zamjad.wordpress.com/2012/08/15/multi-columns-combo-box, for example. What this won't give you compared to ListView is the column headers. Also, the columns will be evenly spaced inside the dropdown but this is what you have in your ListView anyway.
If you want to auto-size them, you'd need to add Width="Auto" SharedSizeGroup="cN" to each ColumnDefinition where "cN" should have the column number instead of N to make them unique within the Grid and add Grid.IsSharedSizeScope="True" to the <ComboBox >
That's a lot of trouble for something that one would expect to be much simpler, but, unfortunately, you cannot place a ListView inside the ComboBox's template, that's a limitation of how the base class Selector works with its items list.
There are other options if you are open to consider 3rd party control libraries. I worked with Syncfusion, they have SfMultiColumnDropDown which does what you want. I'm pretty sure other popular libraries have similar controls as well.

Binding of a check box doesn't transport the values to the model

I've created a list of check boxes and bound them as shown below.
<ListBox ItemsSource="{Binding AllCarrierTypes}">
<ListBox.ItemTemplate>
<DataTemplate>
<CheckBox Content="{Binding Name}"
IsChecked="{Binding Active,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
Checked="ToggleButton_OnChecked"
Unchecked="ToggleButton_OnUnchecked"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
However, when I breakpoint on the unchecked event and see the contents of AllCarrierTypes, using Where() to only get the actives, I see that the list stays the same, despite the fact that those small thingies in the GUI actually are on and off. What can I do to troubleshoot it? According to the things I've read and seen, it supposed to work, so it's likely something stupid I've forgotten...

ComboBox in DataGrid: ItemSource bound to dynamic resource, how to set default row?

I'm working in a C# project [for school], using WPF and implementing MVP. In this code, I've got a DataGrid showing a list of divers. The first column is the Name, and the second column shall show 'DivingType'. DivingType is a built in object, which has a property ID, such as 103A. There are about 400 of these, stored in a list, and each Diver ('row') has a Dives (List<Dive>) Property, and each of these Dives has a divingType property.
What we want to have, is that this column will by default show the DivingType.ID associated with the diver, but that the dropdown list shall contain ALL diving types, such that you shall be able to change it from there [and update the diver object]. To further complicate it, this is one of many views which we add to our window as UserControls.
With that said, here is the code. I've tried to cut out unnecessary clutter which I'm certain has no impact on the result.
<Window ...>
<Window.Resources>
<local:Presenter x:Key="myPresenter"/>
</Window.Resources>
<DockPanel DataContext="{StaticResource myPresenter}">
<UserControl ...>
<DataGrid ItemsSource="{Binding DiverList}" x:Name="datagrid">
<DataGrid.Columns>
<DataGridTextColumn Header="Name" Width="1*" Binding="{Binding Name}"/>
<DataGridTemplateColumn Header="Diving type" Width="1*">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ComboBox ItemsSource="{Binding RelativeSource={RelativeSource AncestorType=UserControl},
Path=DataContext.DivingTypes}"
DisplayMemberPath="ID"
SelectedValue="{Binding Dives[0]}"
SelectedValuePath="divingType">
</ComboBox>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
</UserControl>
</DockPanel>
</Window>
When the program runs I get all DivingTypes.ID inside the combobox, but no selected value. The code does not put any related errors into the output window. I believe that what happens is that it calls DivingType.Equals but passing the DataContext for the row (the Diver) instead of the SelectedValuePath which I specify. Any way to override this behaviour inside XAML? Or is there an easier way to achieve this?
EDIT:
I've since edited the code posted above to be:
<ComboBox ItemsSource="{
Binding RelativeSource={
RelativeSource AncestorType=UserControl
},
Path=DataContext.DivingTypes
}"
SelectedValue="{
Binding Dives[0].divingType, Mode=TwoWay
}"
/>
This makes the correct value show in the combobox at the start, DivingType.ID is loaded from the Diver.Dives[0].divingType, but it still does not set the property when I select a new value in the dropdown box.

Use UpdateSourceTrigger=PropertyChanged.
Explanation here.

Have you tried to implemented INotifyPropertyChanged in your viewmodel and then raise the PropertyChanged event when the SelectedValue gets set.
If this is not working, can you set the SelectedValue
SelectedValue="{Binding Path=divingType, Mode=TwoWay}"

WP7 : access and change controls inside a ListBox DataTemplate based on the data from the database

I know this has been asked before but Im a bit confused !
I'm writing my app with MVVM so far so good. but now I need to know what is the best way to access my controls inside a data template in a listbox.
I want to access them through the code behind and also be able to change them based on the other values from the database !
Here is the view :
<ListBox Margin="0,8,0,0" toolkit:TiltEffect.IsTiltEnabled="True" x:Name="counterlist" ItemsSource="{Binding Groups}" HorizontalAlignment="Center" Tap="list_OnTap"
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Background="Orange" Width="125" Height="125" Margin="6">
<TextBlock Name="name" Foreground="White" Text="{Binding Name}" VerticalAlignment="Center" HorizontalAlignment="Center" TextAlignment="Center" TextWrapping="Wrap"/>
<TextBlock Name="items" Foreground="White" VerticalAlignment="Center" HorizontalAlignment="Center" TextAlignment="Center" TextWrapping="Wrap"/>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<toolkit:WrapPanel/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
</ListBox>
This list box is bound to the Groups Observable collection in my viewModel. Again so far so good.
Now I have a method called
public int ItemsinGroup(int gid)
This method returns number of items in each group but its not simply based on this database and it also get some info from an external source so I cant simply make a query to add this also to the observable collection.
I just need to add this to each item in the list box so that it shows the associated item counts for each group.
I want to be able to change it in the code behind. I mean I want to access each loop of data in code behind as well as XAML (Which we are already doing it through binding) .
If I can do so it will be easy to inject ItemsinGroup results to its related item in the list box loop.
Can I do that by placing my method in viewModel ? but what about the current item in the loop, how can I find out what is the current ID of each Group in the listbox loop ?
I need to know what is the best way to do such things, what usually everyone does in these cases !
Thanks a lot

Your desire to use MVVM and yet update individual items in a collection from code behind seem contradictory.
This simplest solution is probably to get your collection of groups and before you bind them to the UI you loop through them and add the count to the objects in your collection.
Alternatively, if you want to bind the collection as quickly as possible and then update it. You could step through the collection once bound and as long as the objects in your collection implement INotifyPropertyChanged you could update them and have a second TextBlock in the ItemTemplate show this when set.

Editing child objects of a combo box using c# and Wpf

Backgorund
I am currently writing a program that allows a user to select a manufacture from a combo box. The combo box is created in wpf using the following wpf code segment:
<ComboBox Height="23" Margin="40.422,128.423,229.908,0" Name="itemProductManufacture" ToolTip="Click to open drop down menu" VerticalAlignment="Top" Text="Select A Manufacture" SelectionChanged="itemProductManufacture_SelectionChanged" DropDownOpened="itemProductManufacture_DropDownOpened">
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ManufactureId}" Width="0"/>
<Image Name="itemManufactureImage" Source="{Binding ManufactureImage}" Height="15" Width="70" Stretch="Uniform"/>
<TextBlock Text="{Binding ManufactureName}"/>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
The data is provided form a database and each entry has a Image, a name and an Id (intentionally not shown)
Problem
I am trying to code the behaviour of the combo box so when it is open the image height is 50 and when it is closed it is 15 this is so the image is larger when it is first displayed and then smaller once selected so it doesn't take up too much space on the form.
I have tried editing the image propities using code but am unable to accsess it using its name or any other children of the combo box.
Thanks
Jonathan

As you are using data template you won't be able to access the directly by its name.
Try something like this -
Image image = this.itemProductManufacture.ItemTemplate.FindName("itemManufactureImage", this) as Image;
One thing I am not clear is whether you want to change image size for all the items or the selected one? If you need to access the image for a particulat item in combobox you may have to use the ItemContainerGenerator.ContainerFromItem, as explained in following posts -
WPF - ItemsControl - How do I get find my "CheckBox" item that is in the ItemTemplate?
http://www.sitechno.com/Blog/HowToUseAttachedPropertiesAsAnExtensionMechanismForACheckedListbox.aspx
look at this, To know the various ways of finding controls - How can I find WPF controls by name or type?

You can edit image properties from code using binding. Or you can use triggers in Datatemplate. When comboboxitems checked properties change, you can change height property of corresponding image

Try this:
<Image Height = "{Binding Path=IsDropDownOpen,
RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type ComboBox}},
Converter={StaticResource myBoolToHeightConverter}}" />
An example for Converter here