MVVM数据网格到可观察集合的泛型绑定

本文关键字:集合 泛型 绑定 观察 数据 数据网 网格 MVVM | 更新日期: 2023-09-27 18:17:47

我有一个xaml UserControl,其中DataContext指的是一个"Control"-ViewModel。

mc:Ignorable="d" d:DataContext="{d:DesignInstance controls:ControlViewModel}"

此外,我已经将ItemsSource绑定到一个来自"Data"-ViewModel的通用ObservableCollection。(请注意:这些数据仅供演示)

    <DataGrid ItemsSource="{Binding DataCollection}" SelectedItem="{Binding SelectedData}">
        <DataGrid.Columns>
            <DataGridTextColumn Header="Name" Binding="{Binding Name}"/>
            <DataGridTextColumn Header="Age" Visibility="{Binding AgeVisibility}"  Binding="{Binding Age}"/>
        </DataGrid.Columns>
    </DataGrid>

public class ControlViewModel
{
        private ObservableCollection<DataViewModel> _dataViewModels;
        public ObservableCollection<DataViewModel> DataViewModels
        {
            get { return _dataViewModels; }
            set
            {
                   _dataViewModels = value;
                    RaisePropertyChanged("DataViewModels");
            }
        }
}

"Data"-ViewModel具有以下属性,我已经将其绑定到特定的DataGridTextColumn(如您所见)。

public class DataViewModel
{
        private string _name;
        public string Name
        {
            get { return _name; }
            set
            {
                _name = value;
                RaisePropertyChanged("Name");
            }
        }
        private int _age;
        public int Age
        {
            get { return _age; }
            set
            {
                _age = value;
                RaisePropertyChanged("Age");
            }
        }
        private Visibility _ageVisibility;
        public Visibility AgeVisibility
        {
            get { return _ageVisibility; }
        }
}

一切正常,期望"Age"列的visibility属性不会轻易引用Observable Collection的通用DataViewModel (Properties),比如Binding属性。所以这是无法解决的,它总是处于默认状态

MVVM数据网格到可观察集合的泛型绑定

如果你想要一个可绑定的属性,那么在控制只读属性的属性中添加第二个RaisePropertyChanged

public class DataViewModel
{
    //other stuff
    private int _age;
    public int Age
    {
        get { return _age; }
        set
        {
            _age = value;
            RaisePropertyChanged("Age");
            RaisePropertyChanged("AgeVisibility");
        }
    }
    public Visibility AgeVisibility
    {
        get { return this.Age > 0 ? Visibility.Visible : Visibility.Hidden; }
    }
}

你也可以像这样使用类型转换器