Question

请先看一下图片。

当用户输入数字x和mcX时，修改该单元格后，X'应该会自动计算并显示在表格中。

但是，如果我修改X和mcX的值，它将反映在表格上，并且在后面的代码上，我可以看到X'被正确修改，但是没有显示出来。它只会在我尝试修改其单元格时显示。

而且，我对数据库没有任何操作。

这是代码，

MainWindow.xaml

<DataGrid Name="PupilGrid" HeadersVisibility="All" SelectionUnit="CellOrRowHeader" AutoGenerateColumns="False" 
                  CanUserAddRows="True" CanUserSortColumns="True" CanUserResizeColumns="True" IsReadOnly="False" 
                  ItemsSource="{Binding}" CellEditEnding="PupilGrid_OnCellEditEnding">
            <DataGrid.Columns>
                <DataGridTextColumn Header="Frame Number" Binding="{Binding FrameNum, Mode=TwoWay}" />
                <DataGridTextColumn Header="X" Binding="{Binding ObservedCenterX, Mode=TwoWay}" />
                <DataGridTextColumn Header="Y" Binding="{Binding ObservedCenterY}" />
                <DataGridTextColumn Header="mcX" Binding="{Binding MedicalCanthusPositionX}" />
                <DataGridTextColumn Header="mcY" Binding="{Binding MedicalCanthusPositionY}" />
                <DataGridTextColumn Header="X'" Binding="{Binding RelativePupilCenterX}" />
                <DataGridTextColumn Header="Y'" Binding="{Binding RelativePupilCenterY}" />
            </DataGrid.Columns>
        </DataGrid>

MainWindow.xaml.cs

    private MainViewModel vm = new MainViewModel();

    public MainWindow()
    {
        InitializeComponent();



        vm.PupilList = new ObservableCollection<Pupil>();


        vm.PupilList.Add(new Pupil()
        {
            ObservedCenterX = 2.0,
            ObservedCenterY = 1.1,
            MedicalCanthusPositionX = 3.3,
            MedicalCanthusPositionY = 4.2,
            FrameNum = 4
        });
        vm.updatePupilList();
        PupilGrid.ItemsSource = vm.PupilList;
    }

    private void PupilGrid_OnCellEditEnding(object sender, DataGridCellEditEndingEventArgs e)
    {
        vm.updatePupilList();
    }

MainViewModel.cs

    public class MainViewModel : ViewModelBase, INotifyPropertyChanged
{
    /// <summary>
    /// Initializes a new instance of the MainViewModel class.
    /// </summary>
    public MainViewModel()
    {

    }

    public event PropertyChangedEventHandler PropertyChanged = delegate { };


    private double MedicalCanthusX = 29.02;
    private double MedicalCanthusY = 16.50;


    private Pupil _Model;

    public Pupil Model
    {
        get => _Model;
        set
        {
            if (_Model != value)
            {
                _Model = value;
                // raise property change
                // on modal change
            }
        }
    }

    private ObservableCollection<Pupil> _pupilList;

    public ObservableCollection<Pupil> PupilList
    {
        get => _pupilList;
        set
        {

            _pupilList = value;
            Debug.WriteLine(value);
            Debug.WriteLine("new value added");
            updatePupilList();
            PropertyChanged(this, new PropertyChangedEventArgs("RelativePupilCenterX"));
        }
    }

    public void updatePupilList()
    {
        foreach (var pupil in PupilList)
        {
            pupil.RelativePupilCenterX = pupil.ObservedCenterX - pupil.MedicalCanthusPositionX;
            pupil.RelativePupilCenterY = pupil.ObservedCenterY - pupil.MedicalCanthusPositionY;
        }
    }

}

Pupil.cs

    public class Pupil : INotifyPropertyChanged
{

    public event PropertyChangedEventHandler PropertyChanged = delegate { };

    private double _observedCenterX;
    public double ObservedCenterX
    {
        get => _observedCenterX;
        set
        {
            _observedCenterX = value;
            PropertyChanged(this, new PropertyChangedEventArgs("RelativePupilCenterX"));
            PropertyChanged(this, new PropertyChangedEventArgs("ObservedCenterX"));
        } 
    }

    private double _ObservedCenterY;
    public double ObservedCenterY
    {
        get => _ObservedCenterY;
        set
        {
            _ObservedCenterY = value;
            PropertyChanged(this, new PropertyChangedEventArgs("RelativePupilCenterY"));
            PropertyChanged(this, new PropertyChangedEventArgs("ObservedCenterY"));
        }

    }

    private double _medicalCanthusPositionX;

    public double MedicalCanthusPositionX
    {
        get => _medicalCanthusPositionX;
        set
        {
            _medicalCanthusPositionX = value;
            PropertyChanged(this, new PropertyChangedEventArgs("RelativePupilCenterX"));
            PropertyChanged(this, new PropertyChangedEventArgs("MedicalCanthusPositionX"));
        }
    }

    private double _medicalCanthusPositionY;
    public double MedicalCanthusPositionY
    {
        get => _medicalCanthusPositionY;
        set
        {
            _medicalCanthusPositionY = value;
            PropertyChanged(this, new PropertyChangedEventArgs("RelativePupilCenterY"));
            PropertyChanged(this, new PropertyChangedEventArgs("MedicalCanthusPositionY"));
        }
    }

    private double _relativePupilCenterX;
    public double RelativePupilCenterX
    {
        get => _relativePupilCenterX;
        set
        {
            _relativePupilCenterX = value;
            PropertyChanged(this, new PropertyChangedEventArgs("RelativePupilCenterX"));
        }
    }

    private double _relativePupilCenterY;
    public double RelativePupilCenterY
    {
        get => _relativePupilCenterY;
        set
        {
            _relativePupilCenterY = value;
            PropertyChanged(this, new PropertyChangedEventArgs("RelativePupilCenterY"));
        }
    }

    public int FrameNum { get; set; }

}

Answer 1

在提交编辑之前会触发

CellEditEnding ，默认情况下，TextBox的文本会在失去焦点时进行更新。因此，在更改 X 之前，将调用 updatePupilList

在datagrid上进行编辑后，如何在vm中更新数据？

1 个答案: