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我會先發布我的代碼，然後問我的問題。在MVVM應用程序上數據更改不會持久到實體框架
XAML：
<Window
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:FootballPool" mc:Ignorable="d" x:Class="MainWindow"
xmlns:system="clr-namespace:System;assembly=mscorlib"
Title="MainWindow" Height="350" Width="525" Margin="5">
<Window.Resources>
<local:MainWindowVM x:Key="ViewModel" />
<ObjectDataProvider x:Key="YearList"
ObjectType="{x:Type local:MainWindowVM}"
MethodName="YearList" />
<ObjectDataProvider x:Key="WeekList"
ObjectType="{x:Type local:MainWindowVM}"
MethodName="WeekList">
<ObjectDataProvider.MethodParameters>
<system:Int32>0</system:Int32>
</ObjectDataProvider.MethodParameters>
</ObjectDataProvider>
</Window.Resources>
<Grid>
<TabControl Margin="0,0,0,37">
<TabItem Header="Standings">
<Grid Background="#FFE5E5E5"/>
</TabItem>
<TabItem Header="Users">
<Grid Background="#FFE5E5E5">
<DataGrid
x:Name="dgUsers"
DataContext="{Binding Source={StaticResource ViewModel}}"
ItemsSource="{Binding Users, Mode=TwoWay}" AutoGenerateColumns="False"
IsSynchronizedWithCurrentItem="True"
>
<DataGrid.Columns>
<DataGridTextColumn Binding="{Binding FirstName}" ClipboardContentBinding="{x:Null}" Header="First Name"/>
<DataGridTextColumn Binding="{Binding LastName}" ClipboardContentBinding="{x:Null}" Header="Last Name"/>
<DataGridTextColumn Binding="{Binding Email}" ClipboardContentBinding="{x:Null}" Header="Email"/>
<DataGridTextColumn Binding="{Binding Password}" ClipboardContentBinding="{x:Null}" Header="Password"/>
</DataGrid.Columns>
</DataGrid>
</Grid>
</TabItem>
<TabItem Header="Weekly Settings">
<Grid Background="#FFE5E5E5">
<Grid x:Name="Grid1" HorizontalAlignment="Left" VerticalAlignment="Top" Background="#FFC8C8C8" Margin="238,27,0,0" DataContext="{Binding SelectedItem, ElementName=listBox}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Label Content="Year:" Grid.Column="0" HorizontalAlignment="Left" Margin="3" Grid.Row="0" VerticalAlignment="Center"/>
<TextBox x:Name="Year" Grid.Column="1" HorizontalAlignment="Left" Height="24" Margin="3" Grid.Row="0" Text="{Binding Year, Mode=TwoWay, NotifyOnValidationError=true, ValidatesOnExceptions=true}" VerticalAlignment="Center" Width="120"/>
<Label Content="Week Number:" Grid.Column="0" HorizontalAlignment="Left" Margin="3" Grid.Row="1" VerticalAlignment="Center"/>
<TextBox x:Name="WeekNumberTextBox" Grid.Column="1" HorizontalAlignment="Left" Height="23" Margin="1" Grid.Row="1" Text="{Binding WeekNumber, Mode=TwoWay, NotifyOnValidationError=true, ValidatesOnExceptions=true}" VerticalAlignment="Center" Width="120"/>
<Label Content="Begin Date:" Grid.Column="0" HorizontalAlignment="Left" Margin="3" Grid.Row="2" VerticalAlignment="Center"/>
<DatePicker x:Name="BeginDateDatePicker" Grid.Column="1" HorizontalAlignment="Left" Margin="3" Grid.Row="2" SelectedDate="{Binding BeginDate, Mode=TwoWay, NotifyOnValidationError=true, ValidatesOnExceptions=true}" VerticalAlignment="Center"/>
<Label Content="End Date:" Grid.Column="0" HorizontalAlignment="Left" Margin="3" Grid.Row="3" VerticalAlignment="Center"/>
<DatePicker x:Name="EndDateDatePicker" Grid.Column="1" HorizontalAlignment="Left" Margin="3" Grid.Row="3" SelectedDate="{Binding EndDate, Mode=TwoWay, NotifyOnValidationError=true, ValidatesOnExceptions=true}" VerticalAlignment="Center"/>
<Label Content="Cost:" Grid.Column="0" HorizontalAlignment="Left" Margin="3" Grid.Row="4" VerticalAlignment="Center"/>
<TextBox x:Name="CostTextBox" Grid.Column="1" HorizontalAlignment="Left" Height="23" Margin="3" Grid.Row="4" Text="{Binding Cost, Mode=TwoWay, NotifyOnValidationError=true, ValidatesOnExceptions=true}" VerticalAlignment="Center" Width="120"/>
</Grid>
<Button x:Name="btnNewWeek" Content="New Week" HorizontalAlignment="Left" Height="23" Margin="384,192,0,0" VerticalAlignment="Top" Width="75"/>
<ComboBox x:Name="cboYear"
HorizontalAlignment="Left" Margin="94,14,0,0"
VerticalAlignment="Top" Width="56"
IsSynchronizedWithCurrentItem="True"
ItemsSource="{Binding Mode=OneWay, Source={StaticResource YearList}}">
<ComboBox.SelectedItem>
<Binding Source="{StaticResource WeekList}"
Path="MethodParameters[0]"
BindsDirectlyToSource="True"
UpdateSourceTrigger="PropertyChanged" />
</ComboBox.SelectedItem>
</ComboBox>
<ListBox x:Name="listBox" HorizontalAlignment="Left" Height="136" Margin="95,51,0,0" VerticalAlignment="Top" Width="55" IsSynchronizedWithCurrentItem="True" ItemsSource="{Binding Source={StaticResource WeekList}}" DisplayMemberPath="WeekNumber" />
<Label Content="Year:" HorizontalAlignment="Left" Margin="27,10,0,0" VerticalAlignment="Top"/>
<Label Content="Week:" HorizontalAlignment="Left" Margin="27,51,0,0" VerticalAlignment="Top"/>
</Grid>
</TabItem>
</TabControl>
<Button Content="Save" HorizontalAlignment="Right" Height="27" Margin="0,0,5,5" VerticalAlignment="Bottom" Width="80" Click="Button_Click"/>
</Grid>
</Window>
視圖模型：
Imports System.Collections.ObjectModel
Imports System.ComponentModel
Imports System.Collections.Specialized
Public Class MainWindowVM
Implements INotifyPropertyChanged
Implements INotifyCollectionChanged
Dim dbcontext As New FootballPoolEntities
Private _Users As ObservableCollection(Of User)
Private _Settings As ObservableCollection(Of ScheduleSetting)
Public Property Users As ObservableCollection(Of User)
Get
Return _Users
End Get
Set(value As ObservableCollection(Of User))
_Users = value
RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs("Users"))
End Set
End Property
Public Property Settings As ObservableCollection(Of ScheduleSetting)
Get
Return _Settings
End Get
Set(value As ObservableCollection(Of ScheduleSetting))
_Settings = value
RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs("Settings"))
End Set
End Property
Public Sub New()
_Users = New ObservableCollection(Of User)(dbcontext.Users.ToList)
_Settings = New ObservableCollection(Of ScheduleSetting)(dbcontext.ScheduleSettings.ToList)
AddHandler Users.CollectionChanged, AddressOf OnUsersCollectionChanged
AddHandler Settings.CollectionChanged, AddressOf OnSettingsCollectionChanged
End Sub
Public Event PropertyChanged(sender As Object, e As PropertyChangedEventArgs) Implements INotifyPropertyChanged.PropertyChanged
Public Event CollectionChanged(sender As Object, e As NotifyCollectionChangedEventArgs) Implements INotifyCollectionChanged.CollectionChanged
Private Sub OnUsersCollectionChanged(sender As Object, e As NotifyCollectionChangedEventArgs)
If e.Action = NotifyCollectionChangedAction.Add Then
For Each item In e.NewItems
dbcontext.Users.Add(item)
Next
End If
If e.Action = NotifyCollectionChangedAction.Remove Then
For Each item In e.OldItems
dbcontext.Users.Remove(item)
Next
End If
End Sub
Private Sub OnSettingsCollectionChanged(sender As Object, e As NotifyCollectionChangedEventArgs)
If e.Action = NotifyCollectionChangedAction.Add Then
For Each item In e.NewItems
dbcontext.ScheduleSettings.Add(item)
Next
End If
If e.Action = NotifyCollectionChangedAction.Remove Then
For Each item In e.OldItems
dbcontext.ScheduleSettings.Remove(item)
Next
End If
End Sub
Public Sub SaveChanges()
dbcontext.SaveChanges()
End Sub
Public Sub NewWeek()
Dim newWeek As New ScheduleSetting
Settings.Add(newWeek)
End Sub
Public Function WeekList(SelectedYear As Int32) As ObservableCollection(Of ScheduleSetting)
If SelectedYear = 0 Then
Return Nothing
Exit Function
End If
Return New ObservableCollection(Of ScheduleSetting)(Settings.Where(Function(c) c.Year = SelectedYear).ToList)
End Function
Public Function YearList() As List(Of Int32)
Return dbcontext.ScheduleSettings _
.Select(Function(x) x.Year) _
.Distinct.ToList()
End Function
End Class
我遇到的問題是，我的列表框與設置填充通過 「WeekList」 方法和ObjectDataProvider的對象。我的細節網格有它的datacontext綁定到該列表框的SelectedItem。當我對數據進行更改時，執行savechanges時，它們不會保留回實體框架。我是否在綁定中缺少某些東西，我應該如何處理主 - 細節？或者我需要添加ViewModel中的某些東西？
我感謝任何人可以提供幫助。謝謝。