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WPF ListView - detect ListVewItem when selected item is not clicked

I'm trying to get an item in ListView in WPF when user doesn't select an item by clicking on it but the user taps on it.
Is there a way to achieve this in WPF ListView.
ListView dataSource is filled by a dynamic collection in code-behind.
I'm getting a null object when user taps on it.
Item selectedItem = (Item)lv_CartItems.SelectedItem;
this is how my data-template looks like for listview.
<ListView.ItemTemplate>
<DataTemplate>
<Viewbox>
<Grid Width="230" Height="110" >
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition Width=".1*" />
<ColumnDefinition />
<ColumnDefinition/>
<ColumnDefinition/>
<ColumnDefinition Width=".5*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="2*" />
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<Border BorderBrush="LightGray" BorderThickness="1"
Grid.Row="0" Grid.Column="0"
Grid.ColumnSpan="6" Grid.RowSpan="3" >
</Border>
<Viewbox Grid.Row="0" >
<Image Name="img_ItemImage"
Source="{Binding Image, Mode=TwoWay }"
Width="20" Height=" 25" />
</Viewbox>
<Viewbox Grid.Column="2" Grid.ColumnSpan="3" VerticalAlignment="Top" >
<TextBlock Name="lbl_ItemName" TextWrapping="Wrap" Width="180" Foreground="Gray"
Text="{Binding Name , Mode=TwoWay }" Tag="{Binding SKU_No,Mode=TwoWay}" >
</TextBlock>
</Viewbox>
<Viewbox Grid.Row="1" Margin="10,0" VerticalAlignment="Top" >
<TextBlock Foreground="Gray" >Qty:</TextBlock>
</Viewbox>
<Viewbox Grid.Row="2" Margin="0,0" VerticalAlignment="Top" >
<StackPanel Orientation="Horizontal" >
<Button Name="btn_Minus" FontWeight="ExtraBold" Padding="0" Width="12"
Resources="{StaticResource cartitembutton}" Click="btn_Minus_Click" >
<Image Source="/Resources\Icons\minus.png" ></Image>
</Button>
<Border BorderThickness="1" Margin="2,0" Width="13" CornerRadius="2" BorderBrush="LightGray" >
<TextBlock Name="lbl_Quantity" FontWeight="Bold" Foreground="Gray"
HorizontalAlignment="Center" VerticalAlignment="Center"
Text="{Binding Quantity , Mode=TwoWay }">
</TextBlock>
</Border>
<Button Name="btn_Increment" FontWeight="ExtraBold" Width="12"
Resources="{StaticResource cartitembutton}"
Padding="0"
Click="btn_Increment_Click">
<Image Source="/Resources\Icons\union_10.png" ></Image>
</Button>
</StackPanel>
</Viewbox>
<Viewbox Grid.Row="1" Grid.Column="2" Margin="5,0"
HorizontalAlignment="Left" Grid.ColumnSpan="3" >
<TextBlock Name="lbl_Price" FontWeight="DemiBold"
Text="{Binding Price , Mode=TwoWay}" ></TextBlock>
</Viewbox>
<Viewbox Grid.Row="2" Grid.Column="2" Grid.ColumnSpan="3"
VerticalAlignment="Top" Margin="0,0" >
<TextBlock Name="lbl_Appearence"
Text="{Binding Appearance , Mode=TwoWay }"
TextWrapping="Wrap" Foreground="Gray" Width="210" >
</TextBlock>
</Viewbox>
<Viewbox Grid.Column="5" HorizontalAlignment="Center" VerticalAlignment="Top" Margin="2,2"
>
<Button Name="btn_DeleteItem"
Click="btn_DeleteItem_Click"
Resources="{StaticResource cartitembutton}" >
<Image Source="/Resources/Icons/delete.png" ></Image>
</Button>
</Viewbox>
</Grid>
</Viewbox>
</DataTemplate>
</ListView.ItemTemplate>

You should use data binding to retrieve the selected item. The source property will be automatically updated when the ListView.SelectedItem changes.
Touch is handled the same way as click is handled. The framework converts touch events to mouse events.
I noticed that you wrapped every element into a ViewBox. That is not necessary and will only degrade performance. When the elements are hosted inside a Grid they will resize automatically by default. Exceptions are elements that need an initial size like Shape or Image. But since the item containers won't resize themselves, the content of the containers won't resize too.
To force all elements to occupy max horizontal space you can set a Style that targets the item container:
<ListView.ItemContainerStyle>
<Style TargetType="ListBoxItem">
<Setter Property="HorizontalContentAlignment"
Value="Stretch" />
</Style>
</ListView.ItemContainerStyle>
MainWindow.xaml.cs
public partial class MainWindow : Window
{
public static readonly DependencyProperty ItemsProperty = DependencyProperty.Register(
"Items",
typeof(ObservableCollection<Item>),
typeof(MainWindow),
new PropertyMetadata(default(ObservableCollection<Item>)));
public ObservableCollection<Item> Items
{
get => (ObservableCollection<Item>) GetValue(MainWindow.ItemsProperty);
set => SetValue(MainWindow.ItemsProperty, value);
}
public static readonly DependencyProperty SelectedItemProperty = DependencyProperty.Register(
"SelectedItem",
typeof(Item),
typeof(MainWindow),
new PropertyMetadata(default(Item), MainWindow.OnSelectedItemChanged));
public Item SelectedItem
{
get => (Item) GetValue(MainWindow.SelectedItemProperty);
set => SetValue(MainWindow.SelectedItemProperty, value);
}
public MainWindow()
{
InitializeComponent();
this.DataContext = this;
this.Items = new ObservableCollection<Item>();
// Initialize data source
CreateItems();
}
// Property changed callback of the SelectedItem property
private static void OnSelectedItemChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
// Reference to instance members in a class scope
var _this = d as MainWindow;
if (e.NewValue is ItemCollection selectedItem)
{
// Handle currently selected item
}
}
}
MainWindow.xaml
<Window>
<ListView ItemsSource="{Binding Items}"
SelectedItem="{Binding SelectedItem}" />
</Window>

How to change the background color of TreeViewItem when clicking in the WPF treeview?

I want to change the background of StackPanel when clicking TextBlock.
enter image description here
now background is bule! I want to change it!
<TreeView Name="tvView" HorizontalAlignment="Left" VerticalAlignment="Top" BorderThickness="0">
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Path=ChildNodes}">
<Grid VerticalAlignment="Top" Margin="0">
<StackPanel Orientation="Horizontal" d:LayoutOverrides="Height">
<TextBlock Name="ConfidenceLevelReminderText" Text="！" FontWeight="Bold" HorizontalAlignment="Center" Foreground="#FF0000" Width="{Binding Path=ConfidenceLevelWidth}" Margin="0,0,0,0"></TextBlock>
<TextBlock TextWrapping="Wrap"
Padding="0,3,0,3"
Text="{Binding Path=Name}"
ToolTip="{Binding Path=NameToolTip}"
Tag="{Binding Path=TagInfo}"
MouseLeftButtonDown="name_MouseLeftButtonDown"
FontSize="14"
VerticalAlignment="Center"
HorizontalAlignment="Center"
Foreground="#FF666666"
Margin="0"
Width="{Binding Path=TextWidth}"
Cursor="Hand"/>
<Button x:Name="btnIngnore" Width="{Binding Path=IgnoreWidth}" Click="btn_ignore_Click" Tag="{Binding Path=NodeId}" Margin="0" BorderThickness="0" Background="{x:Null}" Style="{StaticResource ButtonStyle32}" IsEnabled="{Binding Path=IgnoreWidth,Converter={StaticResource itb}}" Cursor="Hand">
<TextBlock Text="xxxx" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0" FontSize="12" Foreground="#FF666666"/>
</Button>
</StackPanel>
</Grid>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>

If you want
to change the background of StackPanel when clicking TextBlock.
You can add EventSetter to the TextBlock's Style and handle event in the event handler.
<TextBlock Text="...">
<TextBlock.Style>
<Style TargetType="TextBlock">
<EventSetter Event="MouseDown" Handler="Mouse_LBtnDown"/>
</Style>
</TextBlock.Style>
</TextBlock>
private void Mouse_LBtnDown(object sender, MouseButtonEventArgs e)
{
StackPanel stp = null;
var visParent = VisualTreeHelper.GetParent(sender as FrameworkElement);
while (stp == null && visParent != null)
{
stp = visParent as StackPanel;
visParent = VisualTreeHelper.GetParent(visParent);
}
if (stp == null) { return; }
stp.Background = Brushes.Coral;
}
For make it reusable and adjustable you could make a behavior from the event handler.
If you don't want what you have asked, then rethink your question and ask new one.

Add UserControl dynamically in WPF C#

I've got one page in my WPF app that should display some "tiles" in number as I specify before. Tile looks like this:
So my page should look something like this:
It is achievable of course by manually cloning tiles, but I want to avoid this (achieve it in more programmatic way). So instead of creating 6 clones I should stick to only one and then if needed add remaining ones. How can I accomplish that? I guess I should create my own UserControl like this:
<Grid HorizontalAlignment="Left" Height="199" VerticalAlignment="Top" Width="207" Background="Black">
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition Height="0*"/>
</Grid.RowDefinitions>
<Image x:Name="image1" HorizontalAlignment="Left" Height="175" VerticalAlignment="Top" Width="207" Stretch="UniformToFill"/>
<Grid HorizontalAlignment="Left" Height="30" VerticalAlignment="Top" Width="112" Background="#FFC78D10">
<TextBox IsReadOnly = "True" x:Name="CategoryOfEvent" Height="30" TextWrapping="Wrap" Text="Category" Width="112" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="White" FontSize="18" SelectionBrush="{x:Null}" HorizontalAlignment="Left" VerticalAlignment="Top" >
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
</Grid>
<TextBox IsReadOnly = "True" x:Name="HourOfEvent" HorizontalAlignment="Left" Height="28" Margin="0,42,0,0" TextWrapping="Wrap" Text="Hour" VerticalAlignment="Top" Width="148" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="#FFE2E2E2" FontSize="22" SelectionBrush="{x:Null}" FontWeight="Bold" TextChanged="HourOfEvent_TextChanged">
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
<TextBox IsReadOnly = "True" x:Name="TitleOfEvent" HorizontalAlignment="Left" Height="88" Margin="0,82,0,0" TextWrapping="Wrap" Text="Title" VerticalAlignment="Top" Width="207" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="White" FontSize="20" SelectionBrush="{x:Null}" FontWeight="Bold">
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
<TextBox IsReadOnly = "True" x:Name="PlaceOfEvent" HorizontalAlignment="Left" Height="24" Margin="0,175,0,0" TextWrapping="Wrap" Text="Where" VerticalAlignment="Top" Width="207" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="White" FontSize="14" SelectionBrush="{x:Null}">
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
</Grid>
and just add them to my page. I would like also to mention that in every tiles there are 4 textboxes which are displaying some data parsed from Json, so maybe some automatic binding should do the job?

It is as simple as that.Firstly,what you can do is,create a UserControl with all your controls inside like TextBlocks and others.Then,decide which type of container control you want to use to hold your UserControl.Let's assume it's a grid.You can specify/set grid's column/rows for each user control.A sample :
private void addControl()
{
UserControl1 MyCon = new UserControl1;
MyGrid.Children.Add(MyCon);
Grid.SetRow(MyCon , 1); ////replace 1 with required row count
}
You can create grid rows in design time,or u can do it in code behind as well :
MyGrid.RowDefinitions.Add(new RowDefinition);
If you want to use columns instead,just apply same code but change Row/Rowdefinition with Column/ColumnDefinition
Hope this helps :)

The follwing example shows how to create multiple of the tiles you have been posting using a DataTemplate and WrapPanel. The DataTemplate specifies how an object (in this case a TileItem) is visualized. You can create multiple TileItems and then add them to an collection, in order to visualize them all.
Assuming your UI resides in MainWindow, you can create a collection with three items in it.
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
TileItemCollection = new ObservableCollection<TileItem>(new []
{
new TileItem(){Category = "Alpha", Hour = "10", Title = "Hello World", Where = "Office"},
new TileItem(){Category = "Beta", Hour = "15", Title = "Test", Where = "Home"},
new TileItem(){Category = "Gamma", Hour = "44", Title = "My Title", Where = "Work"},
});
DataContext = this;
}
public ObservableCollection<TileItem> TileItemCollection { get; }
}
You could load your Items from JSON and create an TileItem for each one in the JSON document. The class for TileItemss can be found below.
public class TileItem : INotifyPropertyChanged
{
private string _hour;
private string _title;
private string _where;
private string _category;
public string Category
{
get => _category;
set
{
if (value == _category) return;
_category = value;
OnPropertyChanged();
}
}
public string Hour
{
get => _hour;
set
{
if (value == _hour) return;
_hour = value;
OnPropertyChanged();
}
}
public string Title
{
get => _title;
set
{
if (value == _title) return;
_title = value;
OnPropertyChanged();
}
}
public string Where
{
get => _where;
set
{
if (value == _where) return;
_where = value;
OnPropertyChanged();
}
}
public event PropertyChangedEventHandler PropertyChanged;
[NotifyPropertyChangedInvocator]
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
Note that in order for datachanges to be propagated to the UI, all properties which should be updated in the UI when you update them in code need to raise the property changed event. In this example all properties do this by default.
You can then update the XAML to bind to a collection. The ItemsControl acts as a container for the tiles. If you scroll down further you may notice the use of WrapPanel which is responsible for the item wrapping effect when you resize the control.
<ItemsControl ItemsSource="{Binding TileItemCollection}" Margin="20">
<ItemsControl.ItemTemplate>
<DataTemplate DataType="{x:Type local:TileItem}" >
<Grid HorizontalAlignment="Left" Height="199" VerticalAlignment="Top" Width="207" Background="Black">
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition Height="0*"/>
</Grid.RowDefinitions>
<Image x:Name="image1" HorizontalAlignment="Left" Height="175" VerticalAlignment="Top" Width="207" Stretch="UniformToFill"/>
<Grid HorizontalAlignment="Left" Height="30" VerticalAlignment="Top" Width="112" Background="#FFC78D10">
<TextBox IsReadOnly="True" Height="30" TextWrapping="Wrap" Text="{Binding Path=Category}" Width="112" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="White" FontSize="18" SelectionBrush="{x:Null}" HorizontalAlignment="Left" VerticalAlignment="Top" >
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
</Grid>
<TextBox IsReadOnly="True" HorizontalAlignment="Left" Height="28" Margin="0,42,0,0" TextWrapping="Wrap" Text="{Binding Path=Hour}" VerticalAlignment="Top" Width="148" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="#FFE2E2E2" FontSize="22" SelectionBrush="{x:Null}" FontWeight="Bold">
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
<TextBox IsReadOnly="True" HorizontalAlignment="Left" Height="88" Margin="0,82,0,0" TextWrapping="Wrap" Text="{Binding Path=Title}" VerticalAlignment="Top" Width="207" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="White" FontSize="20" SelectionBrush="{x:Null}" FontWeight="Bold">
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
<TextBox IsReadOnly="True" x:Name="PlaceOfEvent" HorizontalAlignment="Left" Height="24" Margin="0,175,0,0" TextWrapping="Wrap" Text="{Binding Path=Where}" VerticalAlignment="Top" Width="207" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="White" FontSize="14" SelectionBrush="{x:Null}">
<TextBox.Template>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer Name="PART_ContentHost"/>
</ControlTemplate>
</TextBox.Template>
</TextBox>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.Template>
<ControlTemplate>
<ScrollViewer>
<ItemsPresenter />
</ScrollViewer>
</ControlTemplate>
</ItemsControl.Template>
</ItemsControl>
Each Tile is bound to an TileItem which means that the Bindings which point to e.g. Category, point to the Category of an TileItem.
To increase reusability it would be possible to move the code into its own usercontrol and optionally to add DependencyPropertys for better control.

List picker not showing items.

I have a list picker when clicking on the control to select another item it seems to look like it is going to work but is all white I can sometimes get it to select another item but cant see what is selected until you are off of it. This is how I have it set up. When I set it to full mode the name space is the only thing that shows not the actual name of the item. All I am trying to do is upon loading the view I need to load the listPicker with values.
<phone:PhoneApplicationPage.Resources>
<DataTemplate x:Name="PickerItemTemplate" >
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding TankTypeName}" Style="{StaticResource PhoneTextNormalStyle}"/>
</StackPanel>
</DataTemplate>
<DataTemplate x:Name="PickerFullModeItemTemplate">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding TankTypeName}" Style="{StaticResource PhoneTextNormalStyle}" FontFamily="{StaticResource PhoneFontFamilyLight}"/>
</StackPanel>
</DataTemplate>
</phone:PhoneApplicationPage.Resources>
<!--ContentPanel - place additional content here-->
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<TextBox Height="72" HorizontalAlignment="Left" Margin="0,50,0,0" Name="TextBoxProjectName" Text="" VerticalAlignment="Top" Width="456" />
<TextBlock Height="30" HorizontalAlignment="Left" Margin="12,28,0,0" Name="TextBlockProjectName" Text="Tank Name:" VerticalAlignment="Top" />
<toolkit:ListPicker Header="Tank Type:" ItemsSource="{Binding TankTypes}"
ItemTemplate="{StaticResource PickerItemTemplate}"
FullModeItemTemplate="{Binding PickerFullModeItemTemplate}"
SelectedItems="{Binding SelectedTankTypes,Mode=TwoWay}"
Height="100" HorizontalAlignment="Left"
Margin="6,144,0,0" Name="ListPickerTankType"
VerticalAlignment="Top" Width="444" >
</toolkit:ListPicker>
</Grid>
View Model
private List<TankType> _tankType;
private ObservableCollection<Object> _selectedTankType= new ObservableCollection<object>();
/// <summary>
/// Collection of Tank Type objects.
/// </summary>
public List<TankType> TankTypes
{
get
{
return _tankType;
}
set
{
if (value != _tankType)
{
_tankType = value;
NotifyPropertyChanged("TankType");
}
}
}
public ObservableCollection<object> SelectedTankTypes
{
get
{
return _selectedTankType;
}
set
{
if (_selectedTankType == value)
{
return;
}
_selectedTankType = value;
NotifyPropertyChanged("SelectedTankTypes");
}
}
This is a edit page so in the constructor of the view.
public TaskDetail()
{
InitializeComponent();
var tankTypeViewModel = new ViewModels.TankVewModel();
tankTypeViewModel.GetTankTypes();
ListPickerTankType.DataContext = tankTypeViewModel;
}
Revised OK I removed the height on the listpicker and now can see it made it bigger so the three items are there. I just cant seem to change the font color to black so I can see it when you click on the listpicker.

Figured it out. I needed to remove the height and set the foreground color to black.

Binding colors to ListPicker

I'm trying to make a ListPicker control that contains a list of levels, with a colored square next to each level. This is what I've got:
<toolkit:ListPicker Grid.Row="1"
x:Name="LevelList"
Header="Level"
ItemCountThreshold="0"
FontFamily="Segoe WP Light">
<toolkit:ListPicker.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Rectangle Fill="{Binding}"
Width="43"
Height="43" />
<TextBlock Text="{Binding}"
Margin="12 0 0 0" />
</StackPanel>
</DataTemplate>
</toolkit:ListPicker.ItemTemplate>
<toolkit:ListPicker.FullModeItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal"
Margin="16 21 0 20">
<Rectangle Fill="{Binding}"
Width="43"
Height="43" />
<TextBlock Text="{Binding}"
Margin="16 0 0 0"
FontSize="43"
FontFamily="{StaticResource PhoneFontFamilyLight}" />
</StackPanel>
</DataTemplate>
</toolkit:ListPicker.FullModeItemTemplate>
</toolkit:ListPicker>
and in the c# part, I have
String[] Level= { "E1", "E2", "E3", "E4", "E5"};
String[] colors = { "#FFE5AD1B", "#FF0050EF", "#FFE51400", "#FF008A00", "#FFAA00FF" };
public TolonPk()
{
InitializeComponent();
this.listaNivel.ItemsSource = Level;
this.listaNivel.ItemsSource = colors;
}
My problem is that I don't know how to bind the Textblock strictly to the Level String array and the rectangle fill to the colors...
I'm probably missing something simple, but I just can't seem to get it...

if toolkit:ListPicker uses its ItemsSource like other WPF ItemsControl subclasses, then you need to have both the Level string and the Color string in the same list.
Make a little struct/class that contains a string for level and a string for color.
public struct LevelAndColor
{
public String Level { get; set; }
public String Color { get; set; }
}
Create some IEnumerable (List, ObservableCollection, etc.) and populate it with your instances of level-color pairs.
In the binding, bind like so:
<StackPanel Orientation="Horizontal">
<Rectangle Fill="{Binding Color}" Width="43" Height="43"/>
<TextBlock Text="{Binding Level}" Margin="12 0 0 0"/>
</StackPanel>