Create pick list from different table in combobox wpf ef6 - wpf

Question

Right up front, I am a newbie. I am creating a window with many comboboxes functioning as pick lists. I have code behind xaml and auto generated files in a wpf ef6 application. I have a table (InspectionTypes) with InspectionsID (Int) and InspectionName (String) properties. In my Estimates window, I have a combobox that I desire to list and view/select an InspectionTypeName and store the InspectionsID in the record.
Here is my XAML portion for the combobox:
{ <ComboBox x:Name="inspectionType1ComboBox"
Grid.Column="2" Grid.Row="1" Height="Auto" Width="200" Margin="3"
HorizontalAlignment="Left" VerticalAlignment="Center"
ItemsSource="{Binding}"
DisplayMemberPath="InspectionType1">
<ComboBox.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel/>
</ItemsPanelTemplate>
</ComboBox.ItemsPanel>
</ComboBox>
}
I have been attempting to use a LINQ query and an ObservableCollection. Currently, I am receiving the exception: System.FormatException: 'Input string was not in a correct format.'
This exception was originally thrown at this call stack:
System.Number.StringToNumber(string, System.Globalization.NumberStyles, ref System.Number.NumberBuffer, System.Globalization.NumberFormatInfo, bool)
System.Number.ParseInt32(string, System.Globalization.NumberStyles, System.Globalization.NumberFormatInfo)
string.System.IConvertible.ToInt32(System.IFormatProvider)
System.Convert.ChangeType(object, System.Type, System.IFormatProvider)
MS.Internal.Data.SystemConvertConverter.Convert(object, System.Type, object, System.Globalization.CultureInfo)
MS.Internal.Data.DynamicValueConverter.Convert(object, System.Type, object, System.Globalization.CultureInfo)
System.Windows.Controls.Primitives.Selector.VerifyEqual(object, System.Type, object, MS.Internal.Data.DynamicValueConverter)
System.Windows.Controls.Primitives.Selector.FindItemWithValue(object, out int)
System.Windows.Controls.Primitives.Selector.SelectItemWithValue(object, bool)
System.Windows.Controls.Primitives.Selector.OnItemsChanged(System.Collections.Specialized.NotifyCollectionChangedEventArgs)
code behind:
private void Window_Loaded(object sender, RoutedEventArgs e)
{
System.Windows.Data.CollectionViewSource estimatesViewSource =
((System.Windows.Data.CollectionViewSource)(this.FindResource("estimatesViewSource")));
System.Windows.Data.CollectionViewSource inspectionTypesViewSource =
((System.Windows.Data.CollectionViewSource)
(this.FindResource("inspectionTypesViewSource")));
context.Estimates.Load();
estimatesViewSource.Source = context.Estimates.Local;
inspectionTypesViewSource.Source = context.InspectionTypes.Local;
FillComboBoxes();
}
private void FillComboBoxes()
{
MIDatabase01Entities1 db = new MIDatabase01Entities1();
//var ItemList = (from d in db.InspectionTypes select new { d.InspectionTypesID,
d.InspectionTypeName }).ToList();
var observablelist = new ObservableCollection<InspectionType>(db.InspectionTypes);
inspectionType1ComboBox.DisplayMemberPath = "InspectionTypeName";
inspectionType1ComboBox.SelectedValuePath = "InspectionTypesID";
inspectionType1ComboBox.SelectedValue = "InspectionTypesID";
//inspectionType1ComboBox.ItemsSource = ItemList;
inspectionType1ComboBox.ItemsSource = observablelist;
}
I have been trying to find an answer for weeks without success. Could you please assist?

Answer 1

Do not set the combobox from xaml.cs using ItemsSource in the method. You can make a property for the same and bind it in xaml. This issue is coming because you are assigning data before the view is rendered.
public partial class MainWindow : Window
{
public ObservableCollection<InspectionType> observablelist { get; set;
public MainWindow()
{
InitializeComponent();
System.Windows.Data.CollectionViewSource cvs = ((System.Windows.Data.CollectionViewSource)(this.FindResource("cvs")));
DataContext = this;
FillComboBoxes();
}
private void FillComboBoxes()
{
observablelist = new ObservableCollection<InspectionType>();
observablelist.Add(new InspectionType()
{
InspectionTypeName = "ABC",
InspectionTypesID = 1
});
}
}
xaml.cs
<Window x:Class="WpfApp1.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:scm="clr-namespace:System.ComponentModel;assembly=WindowsBase"
xmlns:dat="clr-
namespace:System.Windows.Data;assembly=PresentationFramework"
xmlns:local="clr-namespace:WpfApp1"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="500"
Loaded="Window_Loaded">
<Window.Resources>
<CollectionViewSource Source="{Binding observablelist}"
x:Key="cvs">
<CollectionViewSource.SortDescriptions>
<scm:SortDescription PropertyName="InspectionTypeName" />
</CollectionViewSource.SortDescriptions>
<CollectionViewSource.GroupDescriptions>
<dat:PropertyGroupDescription PropertyName="InspectionTypesID" />
</CollectionViewSource.GroupDescriptions>
</CollectionViewSource>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="auto" />
<RowDefinition Height="50" />
<RowDefinition Height="auto" />
</Grid.RowDefinitions>
<ListBox ItemsSource="{Binding Source={StaticResource cvs}}"
DisplayMemberPath="InspectionTypeName"
Name="lb">
<ListBox.GroupStyle>
<x:Static Member="GroupStyle.Default" />
</ListBox.GroupStyle>
</ListBox>
<ComboBox Grid.Row="2"
Height="100"
AllowDrop="True"
Width="100"
DisplayMemberPath="InspectionTypeName"
SelectedValuePath="InspectionTypesID"
ItemsSource="{Binding observablelist}"></ComboBox>
</Grid>
</Window>