Question

我有一个ListView绑定到ObservableCollection。当我的按钮命令更新集合中的项目时，视图不会更新。我也在使用Fody来实现INotifyPropertyChanged。

查看

<ListView ItemsSource="{Binding Path=DatabaseInfos}" VerticalAlignment="Stretch" Margin="10">
    <ListView.View>
        <GridView>
            <GridViewColumn Header="Current Version">
                <GridViewColumn.CellTemplate>
                    <DataTemplate>
                        <TextBox Text="{Binding CurrentVerion}" />
                    </DataTemplate>
                </GridViewColumn.CellTemplate>
            </GridViewColumn>
            <GridViewColumn Header="">
                <GridViewColumn.CellTemplate>
                    <DataTemplate>
                        <Button Content="Test" 
                                Command="{Binding DataContext.CmdButtonClicked, RelativeSource={RelativeSource AncestorType={x:Type ListView}}}" 
                                CommandParameter="{Binding}" />
                    </DataTemplate>
                </GridViewColumn.CellTemplate>
            </GridViewColumn>
        </GridView>
    </ListView.View>
</ListView>

视图模型

public interface IDatabaseViewModel
{
    ObservableCollection<DatabaseInfo> DatabaseInfos { get; set; }
}

[Injectable(InstanceScope.Singleton)]
[ImplementPropertyChanged]
public class DatabaseViewModel : IDatabaseViewModel
{
    private RelayCommand _buttonClicked;
    private ILogger _logger;

    public DatabaseViewModel()
    {
        _logger = ServiceLocator.Default.GetInstance<ILoggerFactory>().GetLogger(this);

        DatabaseInfos = new ObservableCollection<DatabaseInfo>();

        var path = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + @"\CampusInstallerSettings.xml";

        if (File.Exists(path))
        {
            try
            {
                var settings = SettingsReader.LoadSettings(path);

                foreach (var db in settings.DatabaseSettings.DatabaseSettings)
                {
                    var dbInfo = new DatabaseInfo();

                    if (db.ActionCode.Value == "Upgrade")
                        dbInfo.Action = Action.Upgrade;
                    else if (db.ActionCode.Value == "None")
                        dbInfo.Action = Action.None;
                    else if (db.ActionCode.Value == "Remove")
                        dbInfo.Action = Action.Uninstall;
                    else
                        dbInfo.Action = Action.None;

                    dbInfo.SqlServer = db.SQLServer.Value;
                    dbInfo.Database = db.Database.Value;

                    if (db.DBType.Value == "CampusVue")
                        dbInfo.DatabaseType = DatabaseType.CampusVue;

                    if (db.Connection.Value == "Integrated")
                        dbInfo.IntegratedSecurity = true;

                    DatabaseInfos.Add(dbInfo);
                }
            }
            catch (Exception ex)
            {
                _logger.Error(ex);
                throw new Exception("Could not load settings file. " + Environment.NewLine + ex.Message);
            }
        }
        else
        {
            throw new Exception("Could not find settings file @ " + path);
        }
    }

    public ICommand CmdButtonClicked
    {
        get { return _buttonClicked ?? (_buttonClicked = new RelayCommand(ButtonClicked)); }
    }

    public ObservableCollection<DatabaseInfo> DatabaseInfos { get; set; }

    private void ButtonClicked(object o)
    {
        _logger.Info(@"Test button clicked.");

        var dbInfo = o as IDatabaseInfo;

        if (dbInfo != null && !dbInfo.TestConnection())
        {
            MessageBox.Show("Couldn't connect", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
        }
    }
}

模型

public interface IDatabaseInfo
{
    Action Action { get; set; }
    string SqlServer { get; set; }
    string Database { get; set; }
    DatabaseType DatabaseType { get; set; }
    bool IntegratedSecurity { get; set; }
    string Username { get; set; }
    string Password { get; set; }
    string CurrentVersion { get; set; }
    bool TestConnection();
}

[ImplementPropertyChanged]
public class DatabaseInfo : IDatabaseInfo
{
    public Action Action { get; set; }

    public string SqlServer { get; set; }

    public string Database { get; set; }

    public DatabaseType DatabaseType { get; set; }

    public bool IntegratedSecurity { get; set; }

    public string Username { get; set; }

    public string Password { get; set; }

    public string CurrentVersion { get; set; }

    public bool TestConnection()
    {
        if (DbHelper.TestConnection(SqlServer, 1433, Database, Username, Password))
        {
            CurrentVersion = DbHelper.GetDbVersion(SqlServer, 1433, Database, Username, Password);
            return true;
        }
        return false;
    }
}

Answer 1

您没有更新该属性。

public string CurrentVersion { get; set; }

是您要更新的内容。由于您未在设置器中调用OnPropertyChanged，因此TextBox不会更新为新版本。

private string _currentVersion = string.Empty;
public string CurrentVersion
{ 
    get { return _currentVersion };
    set
    {
        _currentVersion = value;
        OnPropertyChanged("CurrentVersion");
    }
}

我猜你的DatabaseInfo就是你的Model;）。在这里您可以选择创建一个返回/设置更新值的小型ViewModel包装类，以便将INPC保留在Model层之外。否则你可以使用上面的代码片段：）

修改

在这种情况下，只需拼写正确;）

TextBox Text =＆＃34; {Binding CurrentVerion }＆＃34;

更新ObservableCollection而不是在命令上更新视图

1 个答案: