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How to get the parant object of TreeViewItem

I want to set a property in my ViewModel with the value of the parent Treeview node, but can't get the right way.
Here is the code:
private void TreeView_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
{
if (e.NewValue.GetType() == typeof(Customer))
{
this.MainViewModel.SelectedCustomer = (Customer)e.NewValue;
this.MainViewModel.FinishConSiteCommand.RaiseCanExecuteChanged();
}
else
{
this.MainViewModel.SelectedConstructionSite = (ConstructionSite)e.NewValue;
// here I want to set "this.MainViewModel.SelectedCustomer" this is the parent node.
this.MainViewModel.FinishConSiteCommand.RaiseCanExecuteChanged();
}
}
And the XAML
<TreeView x:Name="treeView" ItemsSource="{Binding ConstructionSiteDictionary.Values}" SelectedItemChanged="TreeView_SelectedItemChanged">
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding ConstructionSites}">
<Label Content="{Binding DisplayableInfos}"/>
<HierarchicalDataTemplate.ItemTemplate>
<DataTemplate>
<Label Content="{Binding Name}"/>
</DataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView
Can anyone help me? Thanks! :)

Okay I found a solution for my own question:
private void TreeView_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
{
if (e.NewValue.GetType() == typeof(Customer))
{
this.MainViewModel.SelectedCustomer = (Customer)e.NewValue;
this.MainViewModel.FinishConSiteCommand.RaiseCanExecuteChanged();
}
else
{
this.MainViewModel.SelectedConstructionSite = (ConstructionSite)e.NewValue;
Customer customer = null;
foreach (Customer c in this.MainViewModel.ConstructionSiteDictionary.Values)
{
foreach (ConstructionSite site in c.ConstructionSites)
{
ConstructionSite selecetedSite = (ConstructionSite)e.NewValue;
if (site == selecetedSite)
customer = c;
}
}
this.MainViewModel.SelectedCustomer = customer;
this.MainViewModel.FinishConSiteCommand.RaiseCanExecuteChanged();
}
}
This works fine, but the runtime complexity isn't very well, when ConstructionSiteDictionary has a lot of data. Has anyone a better solution?

User defined form, wpf binding controls position

I'm trying to let the user to design his own form and save the controls positions into a DB.
Right now I was able to allow the user to spawn new controls and move them around the form. What I dont know is how to get the position of the controls to my Datacontext. I was able to only bind the width etd...
I was hoping I could bind the canvas.left & canvas.top to datacontext but those are not updated on the renderTransform.
Any Ideas?Thanks for help.
Heres the form back code for moving the controls:
private Control _currentlyDragged;
private Point _currentlyDraggedMouseOffset;
private void Window_PreviewMouseMove(object sender, MouseEventArgs e)
{
if (_currentlyDragged != null)
{
var mousePos = e.GetPosition(this);
var futurePos = e.GetPosition(BuildCanvas);
if (futurePos.X <= 0 || futurePos.Y <= 0 || futurePos.Y >= BuildCanvas.ActualHeight || futurePos.X >= BuildCanvas.ActualWidth)
return;
_currentlyDragged.RenderTransform = new TranslateTransform(mousePos.X - _currentlyDraggedMouseOffset.X, mousePos.Y - _currentlyDraggedMouseOffset.Y);
}
}
private void Window_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
if (_currentlyDragged != null)
_currentlyDragged = null;
ReleaseMouseCapture();
}
private void Window_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
Point pt = e.GetPosition((UIElement)sender);
_hitResultsList.Clear();
VisualTreeHelper.HitTest(this, null, new HitTestResultCallback(MyHitTestResult), new PointHitTestParameters(pt));
if (!_hitResultsList.Where(h => h is Border && ((Border)h).Name == "BuildCanvas").Any())
return;
if (_hitResultsList.Count > 0)
{
foreach (DependencyObject d in _hitResultsList)
{
var parent = VisualTreeHelper.GetParent(d);
if (parent != null && (parent is Label || parent is TextBox))
{
CaptureMouse();
_currentlyDragged = parent as Control;
if (_currentlyDragged.RenderTransform is TranslateTransform)
{
_currentlyDraggedMouseOffset.X = e.GetPosition(this).X - ((TranslateTransform)_currentlyDragged.RenderTransform).X;
_currentlyDraggedMouseOffset.Y = e.GetPosition(this).Y - ((TranslateTransform)_currentlyDragged.RenderTransform).Y;
}
else
{
_currentlyDraggedMouseOffset.X = pt.X;
_currentlyDraggedMouseOffset.Y = pt.Y;
}
return;
}
}
}
_currentlyDragged = null;
}
private HitTestResultBehavior MyHitTestResult(HitTestResult result)
{
_hitResultsList.Add(result.VisualHit);
return HitTestResultBehavior.Continue;
}
Heres the ItemsControl:
<Border x:Name="BuildCanvas" Grid.Column="1" Grid.Row="0" Background="#fff4c9" CornerRadius="10">
<Grid>
<!-- Generated controls -->
<ItemsControl ItemsSource="{Binding TextBoxCollection}" Panel.ZIndex="1">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<Canvas/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBox HorizontalAlignment="Left" VerticalAlignment="Top" Padding="2" IsEnabled="False" Background="White"
Text="{Binding Name, Mode=OneWay}" Width="{Binding Width}">
</TextBox>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<!-- -->
</Grid>
</Border>

Rendertransform is a bad idea. Each textbox is in a container.
You should bind the Canvas.Top and Canvas.Left of the itemcontainer. Something like:
<ItemsControl.ItemContainerStyle>
<Style>
<Setter Property="Canvas.Left" Value="{Binding XviewModelProperty}" />
<Setter Property="Canvas.Top" Value="{Binding YviewModelProperty}" />
</Style>
</ItemsControl.ItemContainerStyle>
Cast the datacontext of your textbox to whatever your viewmodel type is and set XviewModelProperty and YviewModelProperty.
Ensure they raise property changed when set.

How to get selected radio button in selected list item from wpf listbox

Image of the list box is as follows:
Listbox with Dynamic column with check boxes and static radio buttons
I have to look for the selected items from list box and selected radio button for each selected item
<ListBox Height="226" HorizontalAlignment="Left" Margin="404,339,0,0" Name="listBoxItems" VerticalAlignment="Top" Width="282" SelectionChanged="listBoxItems_SelectionChanged" SelectionMode="Multiple">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="10,5,0,0">
<CheckBox Width="130" x:Name="chbPrescr" Content="{Binding}" IsChecked="{Binding RelativeSource={RelativeSource AncestorType={x:Type ListBoxItem}}, Path=IsSelected}">
<!--<TextBlock Text="{Binding}" Width="115"></TextBlock>-->
</CheckBox>
<RadioButton x:Name="rdOD" Width="40" Content ="OD" Checked="rdOD_Checked" />
<RadioButton x:Name="rdBD" Width="40" Content ="BD" Checked="rdBD_Checked"/>
<RadioButton x:Name="rdTDS" Width="40" Content ="TDS" Checked="rdTDS_Checked"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
And at the postback event I am getting selected list item but not the selected radio button for that selected list item
foreach (var items in listBoxItems.SelectedItems)
{
string a = items.ToString();
ItemCollection itemCollection = listBoxItems.Items;
object currentItem = itemCollection.CurrentItem;
}
I need to know how can I get the category for each of the selected medicine. Thanks

You could bind the IsChecked property of the RadioButtons to a source property of your data class:
WPF + MVVM + RadioButton : Handle binding with single property
This is the preferable solution.
The fastest one is probably to find the selected RadioButton in the visual tree:
private void listBoxItems_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
foreach (var items in listBoxItems.SelectedItems)
{
ListBoxItem lbi = listBoxItems.ItemContainerGenerator.ContainerFromItem(items) as ListBoxItem;
if (lbi != null)
{
RadioButton rb = FindVisualChildren<RadioButton>(lbi).FirstOrDefault(x => x.IsChecked == true);
if (rb != null)
{
MessageBox.Show("selected: " + rb.Content.ToString());
}
}
}
}
private static IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject
{
if (depObj != null)
{
int NbChild = VisualTreeHelper.GetChildrenCount(depObj);
for (int i = 0; i < NbChild; i++)
{
DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
if (child != null && child is T)
{
yield return (T)child;
}
foreach (T childNiv2 in FindVisualChildren<T>(child))
{
yield return childNiv2;
}
}
}
}

Reach a TextBlock from a specific ListViewItem from the ListView in Windows Phone 8.1 XAML programmatically

I am a new developer on Windows Phone 8.1, I am try to reach a specific ListView item from the ListView collection and be able to color it or color the TextBock inside of it, But I can't reach the item or reach any of items inside of ListView, Please take a look for my below code :
protected async override void OnNavigatedTo(NavigationEventArgs e)
{
SQLiteRT db1 = new SQLiteRT();
var db_connection = await db1.Connection("MyDB.sqlite");
List<MyTBL> t_list = db1.GetTable("SELECT * FROM MyTBL LIMIT 4 ORDER BY RANDOM() ;");
db_connection.Close();
LV_Options.ItemsSource = t_list;
}
// my List View called LV_Options
private void LV_Options_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ListView lv1 = sender as ListView;
if (lv1 == null)
return;
MyTBL wrd = lv1.SelectedItem as MyTBL;
if (wrd == null)
return;
TextBlock tb = lv1.FindName("TB_AMean1") as TextBlock;
tb.FontSize = 17; // here I got debug error (it not worked !!!!!!!)
var item = LV_Options.Items.ElementAt(3); // this seems not work also !!!!
item.BackColor = Color.LightSteelBlue;
}
As you can see above, I tried to reach a specific item by LV_Options.Items.ElementAt(3) but it doesn't work! I also tried to reach the TextBlock from the selected List view item, but also not worked !
(Updated)
XAML code :
<!-- Title Panel -->
<StackPanel Grid.Row="0" Margin="19,0,0,0">
<TextBlock Name="TB_Rslt" Text="Here result of your answer" Style="{ThemeResource TitleTextBlockStyle}" Margin="0,12,0,0"/>
<TextBlock Text="page title" Margin="0,-6.5,0,26.5" Style="{ThemeResource HeaderTextBlockStyle}" CharacterSpacing="{ThemeResource PivotHeaderItemCharacterSpacing}"/>
</StackPanel>
<!--TODO: Content should be placed within the following grid-->
<Grid Grid.Row="1" x:Name="ContentRoot" Margin="19,10,19,15">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<TextBlock Name="TB_Question" Text="Choose Answer " Margin="0,0,25,0" HorizontalAlignment="Right" FontWeight="Bold" FontSize="22" FontFamily="Verdana" RenderTransformOrigin="0.5,0.5" />
<TextBlock Name="TB_EnWord" Text="" Margin="90,0,15,0" HorizontalAlignment="Left" FontWeight="Bold" FontSize="22" FontFamily="Verdana" RenderTransformOrigin="0.5,0.5" TextAlignment="Right" />
<StackPanel Grid.Row="1" Margin="5,22,0,0">
<ListView Name="LV_Options" SelectionChanged="LV_Options_SelectionChanged">
<ListView.ItemTemplate>
<DataTemplate>
<Grid Margin="6">
<StackPanel VerticalAlignment="Top" Margin="10,0,0,0">
<TextBlock Name="TB_AMean1" Text="{Binding AMean1}" TextWrapping="Wrap"/>
</StackPanel>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackPanel>
<Button Name="Btn_Answer" Content="Ansewr" HorizontalAlignment="Left" Grid.Row="1" VerticalAlignment="Bottom" Click="Btn_Answer_Click"/>
My application is a quiz application that offer 4 choices/options as answers for each question, and when user select a true answer, I want to highlight the true answer(true choice) by make its background to green, and if the user selected wrong answer/option I want to make the background of that answer (a specific List View item) with red.
Any help please ?

You're not going to be able to access an element inside a data template like that. Instead, leverage the binding to a view model to set the color and other view-related properties. First, create a wrapper view model for your data class:
public class MyTBLViewModel : INotifyPropertyChanged
{
public MyTBL Entity
{
get { return _entity; }
}
private readonly MyTBL _entity;
public Brush Highlight
{
get { return _brush; }
set
{
_brush = value;
RaisePropertyChanged("Highlight");
}
}
private Brush _highlight;
public double ItemFontSize
{
get { return _itemFontSize; }
set
{
_itemFontSize = value;
RaisePropertyChanged("ItemFontSize");
}
}
private Brush _itemFontSize;
public MyTBLViewModel(MyTBL entity)
{
_entity = entity;
_highlight = new SolidColorBrush(Colors.Transparent);
_itemFontSize = 12;
}
public event PropertyChangedEventArgs PropertyChanged;
protected void RaisePropertyChanged(string propName)
{
var handler = PropertyChanged;
if (handler != null)
handler(this, new PropertyChangedEventArgs(propName));
}
}
Use this as your ItemsSource:
List<MyTBLViewModel> t_list = db1.GetTable("SELECT * FROM MyTBL LIMIT 4 ORDER BY RANDOM() ;")
.AsEnumerable().Select(entity => new MyTBLViewModel(entity)).ToList();
Now in your view, bind the view elements to "Highlight" and "ItemFontSize", and to any other properties you like:
<ListView.ItemTemplate>
<DataTemplate>
<Grid Margin="6" Background="{Binding Highlight}">
<StackPanel VerticalAlignment="Top" Margin="10,0,0,0">
<TextBlock Name="TB_AMean1" Text="{Binding Entity.AMean1}" TextWrapping="Wrap"
FontSize="{Binding ItemFontSize}"/>
</StackPanel>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
Finally, you can get the data item from the SelectionChangedEventArgs -- use it to update your view-related properties:
private void LV_Options_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
foreach (var item in e.AddedItems.OfType<MyTBLViewModel>())
{
item.Highlight = new SolidColorBrush(Color.LightSteelBlue);
item.ItemFontSize = 17;
}
foreach (var item in e.RemovedItems.OfType<MyTBLViewModel>())
{
item.Highlight = new SolidColorBrush(Colors.Transparent);
item.ItemFontSize = 12;
}
}

var item = LV_Options.Items.ElementAt(3);
This line is incorrect. It will not return you a TextBlock. I don't know what a .BackColor is, and it should not compile. The Items property in a ListView will return you a list of ListViewItems. If you want to access the inside element from a ListViewItem, you'll need to access the ContentTemplateRoot property.
Do not use var ever. It lets you assume that you know the type, whereas if you explicitly typed the declaration you would realize you're doing it wrong.
MyTBL wrd = lv1.SelectedItem as MyTBL;
if (wrd == null)
return;
TextBlock tb = lv1.FindName("TB_AMean1") as TextBlock;
What is a MyTBL type? FindName is only available to framework DependencyObjects so I'm assuming it's a user control? You have to provide a lot more code to show us what you're doing and what you're setting the ListView's ItemsSource and ItemTemplate with and what these errors are and how you have 2 breaking debug errors at once and what the error messages are.
Comprehending runtime error messages is a huge part of being a good developer.

Preselect Value of Treeview inside combobox

I am looking to implement a treeview inside a combobox. Basically I want it to show as a combobox when collapsed but a treeview inside combo box when expanded. When a user clicks on a node, I want it to show in the collapsed combo box. I have got this working so far.
The problem I am having is that how do I show a default value from c# when this combo box is loaded. Please help guys as I am running out of ideas :)
Thanks in advance.
Data Template
<DataTemplate x:Key="TreeViewExpanded" >
<StackPanel>
<TreeView x:Name="DPointTree" Margin="5" ItemsSource="{Binding Datapoint}"
Tag="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ComboBox}}}"
>
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Field}">
<TextBlock Text="{Binding Name}"/>
<HierarchicalDataTemplate.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding}"/>
</DataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>
</StackPanel>
<DataTemplate.Triggers>
<DataTrigger Binding = "{Binding Path=SelectedFieldName, Mode=TwoWay}" Value = "">
<Setter Property = "Visibility" Value = "Collapsed"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
Here is the Xaml
<ComboBox Name="cmbFieldName" Width="150" Background="White" ItemsSource="{Binding}" SelectedItem="{Binding SelectedFieldName , Mode=TwoWay}" >
<ComboBox.ItemTemplateSelector>
<local:TreeViewSelector/>
</ComboBox.ItemTemplateSelector>
</ComboBox>
Here is the DataSet passed to this.
Datapoint _datapoint2 = new Datapoint();
_datapoint2.Name = "Alpha";
_datapoint2.FieldID.Add("Contains Elements");
_datapoint2.Field.Add("1 Year");
_datapoint2.Field.Add("2 Year");
_datapoint2.Field.Add("3 Year");

Try this:
private void TreeView_Loaded(object sender, RoutedEventArgs e)
{
TreeView areaTreeView = sender as TreeView;
// Expand the treeview
if (areaTreeView != null)
{
ExpandCollapseTreeNodes(areaTreeView, true);
}
}
public static void ExpandCollapseTreeNodes(ItemsControl parentContainer, bool isExpanded)
{
foreach (Object item in parentContainer.Items)
{
TreeViewItem currentContainer = parentContainer.ItemContainerGenerator.ContainerFromItem(item) as TreeViewItem;
if (currentContainer != null) // && currentContainer.Items.Count > 0
{
//expand the item
currentContainer.IsExpanded = isExpanded;
//if the item's children are not generated, they must be expanded
if (isExpanded && currentContainer.ItemContainerGenerator.Status != GeneratorStatus.ContainersGenerated)
{
//store the event handler in a variable so we can remove it (in the handler itself)
EventHandler eh = null;
eh = new EventHandler(delegate
{
//once the children have been generated, expand those children's children then remove the event handler
if (currentContainer.ItemContainerGenerator.Status == GeneratorStatus.ContainersGenerated)
{
ExpandCollapseTreeNodes(currentContainer, isExpanded);
currentContainer.ItemContainerGenerator.StatusChanged -= eh;
}
});
currentContainer.ItemContainerGenerator.StatusChanged += eh;
}
//otherwise the children have already been generated, so we can now expand those children
else
{
ExpandCollapseTreeNodes(currentContainer, isExpanded);
}
}
}
}

it is not pretty but works to select a node in the tree
// in code behind after the tree is declared, e.g. after InitializeComponent();
SynchronizationContext.Current.Post(delegate
{
// expand the tree to the selected node after loading
treeView.ExpandAll(); // or if path is known treeView.ExpandPath(...);
SynchronizationContext.Current.Post(delegate
{
treeView.GetContainerFromItem(root.Children[0]).IsSelected = true;
}, null);
}, null);