WPF user control binding dynamic combobox - wpf

Question

I have a select list called Printers which is filled by default, after selecting a value from this select list the list called Trays should be filled but it doesn't. I've tried various methods but it seems to me that I still don't understand what the problem is. In addition, I would like to see a new list after pressing the Add next row button and it would also be full. I tried to use DependencyProperty and INotifyPropertyChanged but I don't think I fully understand the basics of the assumption or my problem is specific.
<UserControl x:Class="TestWPF.User_Controls.TrayItem"
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:local="clr-namespace:TestWPF.User_Controls"
mc:Ignorable="d"
Name="ucTray"
d:DesignHeight="450" d:DesignWidth="800">
<Grid Background="White">
<StackPanel Margin="10" x:Name="spTray" Orientation ="Horizontal" Height="35" HorizontalAlignment="Center">
<Label VerticalAlignment="Center">Trays</Label>
<ComboBox Width="250" VerticalContentAlignment="Center">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding ElementName=ucTray, Path=Trays }" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<Label VerticalAlignment="Center">Documents</Label>
<ComboBox Width="250" VerticalContentAlignment="Center">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Documents , RelativeSource={RelativeSource FindAncestor, AncestorType=UserControl}}" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
</StackPanel>
</Grid>
namespace TestWPF.User_Controls
{
public partial class TrayItem : UserControl
{
public List<string> Trays
{
get { return (List<string>)GetValue(TraysProperty); }
set { SetValue(TraysProperty, value); }
}
// Using a DependencyProperty as the backing store for Trays. This enables animation, styling, binding, etc...
public static readonly DependencyProperty TraysProperty =
DependencyProperty.Register("Trays", typeof(List<string>), typeof(TrayItem), new PropertyMetadata(null));
public List<string> Documents
{
get { return (List<string>)GetValue(DocumentsProperty); }
set { SetValue(DocumentsProperty, value); }
}
// Using a DependencyProperty as the backing store for Documents. This enables animation, styling, binding, etc...
public static readonly DependencyProperty DocumentsProperty =
DependencyProperty.Register("Documents", typeof(List<string>), typeof(TrayItem), new PropertyMetadata(null));
public TrayItem()
{
InitializeComponent();
}
}
}
<Window x:Class="TestWPF.MainWindow"
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:TestWPF"
xmlns:control="clr-namespace:TestWPF.User_Controls"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Grid>
<StackPanel Margin="10" x:Name="spItems">
<StackPanel Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center">
<Label>Printers</Label>
<ComboBox x:Name="cmbPrinterList" Width="300" SelectionChanged="cmbPrinterList_SelectionChanged" ItemsSource="{Binding MyPrinters}">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding}" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
</StackPanel>
<control:TrayItem x:Name="cTray" Trays="{Binding MyTrays, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Documents="{Binding Path = MyDocuments, Mode=TwoWay}">
</control:TrayItem>
</StackPanel>
<Button x:Name="btnAddTray" Margin="10" Width="100" Height="40" Click="btnAddTray_Click" >Add next row</Button>
</Grid>
</Window>
namespace TestWPF
{
public partial class MainWindow : Window, INotifyPropertyChanged
{
public List<string> MyPrinters { get; set; }
public string? _SelectedPrinter;
public string? SelectedPrinter
{
get
{
return _SelectedPrinter;
}
set
{
_SelectedPrinter = value;
}
}
private List<string>? _MyTrays;
public List<string>? MyTrays
{
get
{
return _MyTrays;
}
set
{
_MyTrays = value;
RaisePropertyChanged("SelectedPrinter");
RaisePropertyChanged("MyTrays");
RaisePropertyChanged("MyDocuments");
}
}
public List<string>? MyDocuments { get; set; }
public MainWindow()
{
InitializeComponent();
DataContext = this;
MyPrinters = new List<string>()
{
"Printer_1",
"Printer_2",
"Printer_3"
};
}
private void RaisePropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public event PropertyChangedEventHandler? PropertyChanged;
private void cmbPrinterList_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
string? value = (string?)cmbPrinterList.SelectedItem;
switch (value)
{
case "Printer_1":
MyTrays = new List<string>()
{
"aaa",
"bbb",
"ccc"
};
MyDocuments = new List<string>()
{
"zzz",
"qqq",
"rrr"
};
break;
case "Printer_2":
MyTrays = new List<string>()
{
"111",
"222",
"333"
};
MyDocuments = new List<string>()
{
"666",
"777",
"888"
};
break;
case "Printer_3":
MyTrays = new List<string>()
{
"1dg",
"b2f",
"bs4"
};
MyDocuments = new List<string>()
{
"b2vg",
"eb5",
"asc"
};
break;
}
SelectedPrinter = value;
}
private void btnAddTray_Click(object sender, RoutedEventArgs e)
{
TrayItem trayItem = new TrayItem { DataContext = cTray.DataContext };
spItems.Children.Add(trayItem);
}
}
}