wpf mvvm binding change textBlock text

Question

我有文本块，我想机会从false到true由他的绑定属性。属性已更改为true，但文本框的文本仍然为false。我怎样才能把这件事做好。谢谢你的帮助。

<TextBlock x:Name="resBlock" Grid.Row="3" Grid.ColumnSpan="2" HorizontalAlignment="Center" VerticalAlignment="Center" Width="250" Height="50" Text="{Binding Source={StaticResource Locator}, Path=Main.Result}" TextAlignment="Center" FontSize="30" />

public class MainViewModel : ViewModelBase
{
public MainViewModel()
{
LoginCommand = new RelayCommand(Login);
user = new User();
}
DataService service = new DataService();
public User user { get; set; }
public bool Result { get; set; }

public ICommand LoginCommand { get; }

public async void Login()
{
Result = await service.LoginAsync(user); // get True
}
}

Answer 1

要改变视图模型的控制量，必须实现INotifyPropertyChanged接口。

将MainViewModel更改为:

public class MainViewModel : ViewModelBase, INotifyPropertyChanged
{
public MainViewModel()
{
LoginCommand = new RelayCommand(Login);
user = new User();
}
DataService service = new DataService();
public User user { get; set; }

public ICommand LoginCommand { get; }

public async void Login()
{
Result = await service.LoginAsync(user); // get True
}
private bool result;
public bool Result
{
get { return result; }
set
{
result = value;
OnPropertyChange(nameof(Result));
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChange(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}