UserControl中嵌套DataGrid中的WPF SelectedItem属性

本文介绍了UserControl中嵌套DataGrid中的WPF SelectedItem属性的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 29岁程序员，3月因学历无情被辞！ 我有 UserControl ，让它称为 CustomDataGrid ，其中包含 DataGrid 。剩下的内容没关系。 SelectedItem 属性 DataGrid 必须是 SelectedItem 属性 CustomDataGrid 。我想要使​​用绑定与此属性，因为我使用 MVVM 模式。所以我必须在 CustomDataGrid 中声明 SelectedItem 作为 DependencyProperty 。但是我没有任何想法，我可以正确地使它... 这是如何 DepedencyProperty -s被声明通常： public static readonly DependencyProperty SelectedItemProperty = DependencyProperty.Register（SelectedItem，typeof（Object），typeof （CustomDataGrid）， new FrameworkPropertyMetadata（默认（Object），SelectedItemPropertyCallback） { BindsTwoWayByDefault = true， DefaultUpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged }）; //可选 private static void SelectedItemPropertyCallback（DependencyObject obj，DependencyPropertyChangedEventArgs e） { // dataGrid - DataGrid嵌套在UserControl（（CustomDataGrid）obj）.dataGrid.SelectedItem = e.NewValue; } //显然，它没有与嵌套的dataGrid的任何链接。这就是问题。 public Object SelectedItem { get {return GetValue（SelectedItemProperty）; } set {SetValue（SelectedItemProperty，value）; } } 那么，我如何声明 SelectedItem 属性正确？ 解决方案您可以利用绑定框架将这些属性从底层对象连接到外部容器 假设 CustomDataGrid 为 UserControl class CustomDataGrid：UserControl { public CustomDataGrid（） { Binding b = new Binding SelectedItem）; b.Source = this; b.Mode = BindingMode.TwoWay; dataGrid.SetBinding（DataGrid.SelectedItemProperty，b）; } public object SelectedItem { get {return（object）GetValue（SelectedItemProperty）; } set {SetValue（SelectedItemProperty，value）; } } //使用DependencyProperty作为SelectedItem的后备存储。这使得动画，样式，绑定等... public static readonly DependencyProperty SelectedItemProperty = DependencyProperty.Register（SelectedItem，typeof（object），typeof（CustomDataGrid），new PropertyMetadata（null）） ; } 我创建了一个名为 SelectedItem 在 CustomDataGrid 中，并设置一个双向绑定到 SelectedItem 的实际 dataGrid 所以这将连接这些属性，并将来回传播任何更改。 I have UserControl, lets call it as CustomDataGrid, that contains DataGrid. Remained content doesn't matter. SelectedItem property of DataGrid must be SelectedItem property of CustomDataGrid. And I wanna be able to use Binding with this property, cause I use MVVM pattern. So I have to declare SelectedItem as DependencyProperty in CustomDataGrid. But I have no ideas haw can I make it properly...This is how DepedencyProperty-s is declared usually:public static readonly DependencyProperty SelectedItemProperty = DependencyProperty.Register( "SelectedItem", typeof(Object), typeof(CustomDataGrid), new FrameworkPropertyMetadata(default(Object), SelectedItemPropertyCallback) { BindsTwoWayByDefault = true, DefaultUpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });// Optionallyprivate static void SelectedItemPropertyCallback(DependencyObject obj, DependencyPropertyChangedEventArgs e){ // dataGrid - `DataGrid` nested in `UserControl` ((CustomDataGrid)obj).dataGrid.SelectedItem = e.NewValue;}// Obviously, it has no any link with nested `dataGrid`. This is the problem.public Object SelectedItem{ get { return GetValue(SelectedItemProperty); } set { SetValue(SelectedItemProperty, value); }}So, how can I declare SelectedItem property correctly? 解决方案 You could leverage the binding framework for wiring such properties from underlying objects to outer containersexample assuming CustomDataGrid as UserControl class CustomDataGrid : UserControl { public CustomDataGrid() { Binding b = new Binding("SelectedItem"); b.Source = this; b.Mode = BindingMode.TwoWay; dataGrid.SetBinding(DataGrid.SelectedItemProperty, b); } public object SelectedItem { get { return (object)GetValue(SelectedItemProperty); } set { SetValue(SelectedItemProperty, value); } } // Using a DependencyProperty as the backing store for SelectedItem. This enables animation, styling, binding, etc... public static readonly DependencyProperty SelectedItemProperty = DependencyProperty.Register("SelectedItem", typeof(object), typeof(CustomDataGrid), new PropertyMetadata(null)); }I have created a property called SelectedItem in CustomDataGrid and set a two way binding to SelectedItem of the actual dataGrid inside.so this will wire up these properties and will propagate any changes to and fro. 这篇关于UserControl中嵌套DataGrid中的WPF SelectedItem属性的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 上岸，阿里云！