Question

我有一个WPF应用程序，我正在使用MVVM设计方法。

我有一个ObservableObject，它包含下面的类Transaction的列表;

public Transaction
{
    public string Ammount;
    public string Direction;
}

我的ViewModel中的ObservableObject位于

之下

public ObservableCollection<Transactions> ListOfUserTransactions
        {
            get { return _localTransactionData; }
            set
            {
                _localTransactionData = value;
                RaisePropertyChanged("ListOfUserTransactions");
            }
        }

我的观点以这种方式结合;

<DataGrid ItemsSource="{Binding ListOfUserTransactions}" AutoGenerateColumns="False">
            <DataGrid.Columns>
                <DataGridTextColumn Header="Ammount" Binding="{Binding Path=Ammount}"  Foreground="Black" IsReadOnly="True" />

                <DataGridTextColumn Header="Direction" Binding="{Binding Path=Direction}" Foreground="Black" IsReadOnly="True" />
            </DataGrid.Columns>
</DataGrid>

这确实有效，因为生成的行数与我期望的相同，但所有行都是空的，我认为这是我绑定DataGridTextColumn的方式，但我不确定如何做到这一点，希望有上述问题中有足够的细节。

修改

下面是如何创建交易清单

ObservableCollection<Transaction> _localTransactionData = new ObservableCollection<Transaction>();


        public TransactionsViewModel(User passedThroughUser)
        {
            _user = passedThroughUser;
            _listOfTransactions = _user.Transactions;

            foreach (var item in _listOfTransactions)
            {
                LocalTransactionsList tran = new LocalTransactionsList();
                tran.Ammount = item.Ammount.ToString(); ;
                tran.Direction = item.Direction;
                _localTransactionData.Add(tran);
            }
        }

Answer 1

你的问题在这里：

public Transaction
{
    public string Ammount;
    public string Direction;
}

应该是：

public Transaction
{
    public string Ammount {get;set;}
    public string Direction {get;set;}
}

绑定属性必须具有setter和getter。

Answer 2

您可以通过将Transaction类更改为此来获取您所追求的行为......

public class Transaction : INotifyPropertyChanged
{
    private string _amount;
    public string Amount
    {
        [DebuggerStepThrough]
        get { return _amount; }
        [DebuggerStepThrough]
        set
        {
            if (value != _amount)
            {
                _amount = value;
                OnPropertyChanged("Amount");
            }
        }
    }
    private string _direction;
    public string Direction
    {
        [DebuggerStepThrough]
        get { return _direction; }
        [DebuggerStepThrough]
        set
        {
            if (value != _direction)
            {
                _direction = value;
                OnPropertyChanged("Direction");
            }
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;
    protected virtual void OnPropertyChanged(string name)
    {
        var handler = System.Threading.Interlocked.CompareExchange(ref PropertyChanged, null, null);
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(name));
        }
    }
}

这将使WPF绑定引擎能够访问您的属性并正确绑定它们。

有关INPC的更多信息http://msdn.microsoft.com/en-us/library/system.componentmodel.inotifypropertychanged.aspx

如何显示绑定数据网格的值

2 个答案: