data-binding 相关问题

我有一个 xaml 脚本，它不会监听 OnPropertyChanged。初始化视图时，它可以正常工作，但我无法更新它。零件.xaml：我有一个 xaml 脚本，它不会监听 OnPropertyChanged。初始化视图时，它可以正常工作，但我无法更新它。零件.xaml： <UserControl x:Class="Page_Navigation_App.View.Parts" 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:vm="clr-namespace:Page_Navigation_App.ViewModel" xmlns:utils="clr-namespace:Page_Navigation_App.Utilities" mc:Ignorable="d" d:DesignHeight="600" d:DesignWidth="622" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Style="{StaticResource Page_Style}"> <UserControl.DataContext> <vm:PartsVM x:Name="_model"/> </UserControl.DataContext> ..... <Grid Margin="15"> <Grid.ColumnDefinitions> <ColumnDefinition Width="*" /> <ColumnDefinition Width="5" />  <ColumnDefinition Width="*" />  </Grid.ColumnDefinitions>  <ListView ItemsSource="{Binding TableData}" SelectedItem="{Binding SelectedPart, Mode=TwoWay}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Grid.Column="0" Margin="0,0,0,10" Visibility="{Binding PartsVisibility}"> <ListView.ItemTemplate> <DataTemplate>  <Border Background="#343a40" CornerRadius="10" Padding="10" BorderBrush="#3C3F41" BorderThickness="1" Margin="5" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Grid.ColumnSpan="3" Width="Auto" > <Grid HorizontalAlignment="Stretch" VerticalAlignment="Stretch">  <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="Auto"/> <RowDefinition Height="Auto"/> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition Width="*" /> <ColumnDefinition Width="*" /> <ColumnDefinition Width="*" /> <ColumnDefinition Width="*" /> </Grid.ColumnDefinitions>  <TextBlock Text="Image:" FontWeight="Bold" Foreground="White" Margin="0,0,10,0" Grid.Column="0" Grid.Row="0" HorizontalAlignment="Stretch" /> <TextBlock Text="{Binding [ID], UpdateSourceTrigger = PropertyChanged}" Foreground="White" Margin="0,0,20,0" Grid.Column="0" Grid.Row="1" HorizontalAlignment="Stretch" />  <TextBlock Text="Description:" FontWeight="Bold" Foreground="White" Margin="0,0,10,0" Grid.Column="1" Grid.Row="0" HorizontalAlignment="Stretch" /> <TextBlock Text="{Binding [Description],UpdateSourceTrigger=PropertyChanged}" Foreground="White" Margin="0,0,20,0" Grid.Column="1" Grid.Row="1" HorizontalAlignment="Stretch" />  <TextBlock Text="Type:" FontWeight="Bold" Foreground="White" Margin="0,0,10,0" Grid.Column="2" Grid.Row="0" Visibility="{Binding [Type], Converter={StaticResource StringToVisibilityConverter} }" HorizontalAlignment="Stretch" /> <TextBlock Text="{Binding [Type] , UpdateSourceTrigger=PropertyChanged}" Foreground="White" Margin="0,0,20,0" Grid.Column="2" Grid.Row="1" Visibility="{Binding [Type], Converter={StaticResource StringToVisibilityConverter}}" HorizontalAlignment="Stretch" />  <Button Content="Variants" Command="{Binding DataContext.ShowVariantsCommand, RelativeSource={RelativeSource AncestorType={x:Type UserControl}} , UpdateSourceTrigger=PropertyChanged}" CommandParameter="{Binding}" Grid.Column="3" Grid.Row="0" Grid.RowSpan="3" VerticalAlignment="Stretch" Margin="0,10,0,0" HorizontalAlignment="Stretch" Padding="5,2"/> </Grid> </Border> </DataTemplate> </ListView.ItemTemplate> </ListView> Parts.xaml.cs： namespace Page_Navigation_App.View { /// <summary> /// Interaction logic for Customers.xaml /// </summary> public partial class Parts : UserControl { //private PartsVM _model = new PartsVM(); public Parts() { InitializeComponent(); //DataContext = new PartsVM(); } } } PartsVM.cs： using Microsoft.Data.SqlClient; using Page_Navigation_App.Utilities; using System; using System.Collections.ObjectModel; using System.Data; using System.Linq; using System.Windows; using System.Windows.Input; namespace Page_Navigation_App.ViewModel { class PartsVM : Utilities.ViewModelBase { private readonly DBHandler _dbHandler; private static string TCPServer = "*****"; private static string DBCatalog = "*****"; private string _test; //private DBHandler dbHandler; private SqlConnection _sqlConnection; private ObservableCollection<DataRow> _tableData; private DataRow _selectedPart; private ObservableCollection<Variant> _variants; private bool _isViewingVariants; private Visibility _partsVisibility; private Visibility _reversePartsVisibility = Visibility.Collapsed; private ObservableCollection<EndUser> _endUsers; private string tableName = "Sales.Parts"; // Define column names at the class level private readonly ObservableCollection<string> columnNames = new ObservableCollection<string> { "ID", "Description", "Type", "Comment" }; int i = 0; public ObservableCollection<EndUser> EndUsers { get { return _endUsers; } set { _endUsers = value; OnPropertyChanged(nameof(EndUsers)); } } public ObservableCollection<DataRow> TableData { get { return _tableData; } set { _tableData = value; OnPropertyChanged(nameof(TableData)); } } public string Test { get { return _test; } set { _test = value; OnPropertyChanged(nameof(Test)); } } public DataRow SelectedPart { get { return _selectedPart; } set { _selectedPart = value; OnPropertyChanged(); } } public ObservableCollection<Variant> Variants { get { return _variants; } set { _variants = value; OnPropertyChanged(); } } public bool IsViewingVariants { get { return _isViewingVariants; } set { _isViewingVariants = value; OnPropertyChanged(); } } public Visibility PartsVisibility { get { return _partsVisibility; } set { _partsVisibility = value; OnPropertyChanged(); } } public Visibility ReversePartsVisibility { get { return _reversePartsVisibility; } set { _reversePartsVisibility = value; OnPropertyChanged(); } } public ICommand ShowVariantsCommand { get; set; } public ICommand BackToPartsCommand { get; set; } public PartsVM() { _tableData = new ObservableCollection<DataRow>(); SQLConnectionManager.Initialize(); _sqlConnection = SQLConnectionManager.GetConnection(); if (_sqlConnection == null) { throw new InvalidOperationException("Database connection is not initialized."); } _dbHandler = new DBHandler(_sqlConnection); GetAll(); //Search("test"); } public void GetAll() { i++; string query = $"SELECT * FROM {tableName};"; var dataTable = new DataTable(); using (var command = new SqlCommand(query, _sqlConnection)) { using (var adapter = new SqlDataAdapter(command)) { // Fill the DataTable with the result of the query adapter.Fill(dataTable); } } this.Test = i.ToString(); // Convert DataTable rows to ObservableCollection<DataRow> var rows = new ObservableCollection<DataRow>(dataTable.AsEnumerable()); // Clear the existing TableData and add the new rows TableData.Clear(); /*foreach (var row in rows) { TableData.Add(row); }*/ TableData = rows; // Notify that TableData has changed //OnPropertyChanged(nameof(TableData)); } public void Search(string searchTerm) { // Escape special characters in searchTerm for SQL LIKE string escapedSearchTerm = "%" + searchTerm + "%"; // Generate the LIKE clause for each column string likeClause = string.Join(" OR ", columnNames.Select(col => $"{col} LIKE @searchTerm")); string query = $"SELECT * FROM {tableName} WHERE {likeClause};"; //MessageBox.Show(query); var dataTable = new DataTable(); using (var command = new SqlCommand(query, _sqlConnection)) { // Add the parameter once to be used in all LIKE statements command.Parameters.AddWithValue("@searchTerm", escapedSearchTerm); using (var adapter = new SqlDataAdapter(command)) { // Fill the dataTable with the query result adapter.Fill(dataTable); } } var rows = new ObservableCollection<DataRow>(dataTable.AsEnumerable()); int test = TableData.Count; // Convert DataTable rows to an ObservableCollection of DataRow TableData.Clear(); foreach (DataRow row in rows) { TableData.Add(row); } TableData = rows; } } } ViewmodelBase： namespace Page_Navigation_App.Utilities { class ViewModelBase : INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; public void OnPropertyChanged([CallerMemberName] string propName = null) { PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propName)); } } } 我知道函数被触发了，因为我已经调试过了。搜索功能由不同脚本中的函数触发。我还知道 DataTable 正在正确更新，但 UI 不会更新。我尝试手动触发 PropertyChanged，无论是否显式设置 UpdateSourceTrigger。我不知道为什么这不起作用。预先感谢您使用的语法无效，这里正确的绑定语法是： <TextBlock Text="{Binding ID}" />

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