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
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