我正在尝试通过执行Drag & Drop
我找到了一些解决方案（在Stackoverflow上并通过谷歌搜索）并使用它们我试图做出这个行为......我从Hordcodenet网站上拿了例子（我现在没有链接）
public static class DragDropRowBehavior
{
private static DataGrid dataGrid;
private static Popup popup;
private static bool enable;
private static object draggedItem;
public static object DraggedItem
{
get { return DragDropRowBehavior.draggedItem; }
set { DragDropRowBehavior.draggedItem = value; }
}
public static Popup GetPopupControl(DependencyObject obj)
{
return (Popup)obj.GetValue(PopupControlProperty);
}
public static void SetPopupControl(DependencyObject obj, Popup value)
{
obj.SetValue(PopupControlProperty, value);
}
// Using a DependencyProperty as the backing store for PopupControl. This enables animation, styling, binding, etc...
public static readonly DependencyProperty PopupControlProperty =
DependencyProperty.RegisterAttached("PopupControl", typeof(Popup), typeof(DragDropRowBehavior), new UIPropertyMetadata(null, OnPopupControlChanged));
private static void OnPopupControlChanged(DependencyObject depObject, DependencyPropertyChangedEventArgs e)
{
if (e.NewValue == null || !(e.NewValue is Popup))
{
throw new ArgumentException("Popup Control should be set", "PopupControl");
}
popup = e.NewValue as Popup;
dataGrid = depObject as DataGrid;
// Check if DataGrid
if (dataGrid == null)
return;
if (enable && popup != null)
{
dataGrid.BeginningEdit += new EventHandler<DataGridBeginningEditEventArgs>(OnBeginEdit);
dataGrid.CellEditEnding += new EventHandler<DataGridCellEditEndingEventArgs>(OnEndEdit);
dataGrid.MouseLeftButtonUp += new System.Windows.Input.MouseButtonEventHandler(OnMouseLeftButtonUp);
dataGrid.MouseLeftButtonDown += new MouseButtonEventHandler(OnMouseLeftButtonDown);
dataGrid.MouseMove += new MouseEventHandler(OnMouseMove);
}
else
{
dataGrid.BeginningEdit -= new EventHandler<DataGridBeginningEditEventArgs>(OnBeginEdit);
dataGrid.CellEditEnding -= new EventHandler<DataGridCellEditEndingEventArgs>(OnEndEdit);
dataGrid.MouseLeftButtonUp -= new System.Windows.Input.MouseButtonEventHandler(OnMouseLeftButtonUp);
dataGrid.MouseLeftButtonDown -= new MouseButtonEventHandler(OnMouseLeftButtonDown);
dataGrid.MouseMove -= new MouseEventHandler(OnMouseMove);
dataGrid = null;
popup = null;
draggedItem = null;
IsEditing = false;
IsDragging = false;
}
}
public static bool GetEnabled(DependencyObject obj)
{
return (bool)obj.GetValue(EnabledProperty);
}
public static void SetEnabled(DependencyObject obj, bool value)
{
obj.SetValue(EnabledProperty, value);
}
// Using a DependencyProperty as the backing store for Enabled. This enables animation, styling, binding, etc...
public static readonly DependencyProperty EnabledProperty =
DependencyProperty.RegisterAttached("Enabled", typeof(bool), typeof(DragDropRowBehavior), new UIPropertyMetadata(false,OnEnabledChanged));
private static void OnEnabledChanged(DependencyObject depObject,DependencyPropertyChangedEventArgs e)
{
//Check if value is a Boolean Type
if (e.NewValue is bool == false)
throw new ArgumentException("Value should be of bool type", "Enabled");
enable = (bool)e.NewValue;
}
public static bool IsEditing { get; set; }
public static bool IsDragging { get; set; }
private static void OnBeginEdit(object sender, DataGridBeginningEditEventArgs e)
{
IsEditing = true;
//in case we are in the middle of a drag/drop operation, cancel it...
if (IsDragging) ResetDragDrop();
}
private static void OnEndEdit(object sender, DataGridCellEditEndingEventArgs e)
{
IsEditing = false;
}
/// <summary>
/// Initiates a drag action if the grid is not in edit mode.
/// </summary>
private static void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
if (IsEditing) return;
var row = UIHelpers.TryFindFromPoint<DataGridRow>((UIElement)sender, e.GetPosition(dataGrid));
if (row == null || row.IsEditing) return;
//set flag that indicates we're capturing mouse movements
IsDragging = true;
DraggedItem = row.Item;
}
/// <summary>
/// Completes a drag/drop operation.
/// </summary>
private static void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
if (!IsDragging || IsEditing)
{
return;
}
//get the target item
var targetItem = dataGrid.SelectedItem;
if (targetItem == null || !ReferenceEquals(DraggedItem, targetItem))
{
//remove the source from the list
((dataGrid).ItemsSource as IList).Remove(DraggedItem);
//get target index
var targetIndex = ((dataGrid).ItemsSource as IList).IndexOf(targetItem);
//move source at the target's location
((dataGrid).ItemsSource as IList).Insert(targetIndex, DraggedItem);
//select the dropped item
dataGrid.SelectedItem = DraggedItem;
}
//reset
ResetDragDrop();
}
/// <summary>
/// Closes the popup and resets the
/// grid to read-enabled mode.
/// </summary>
private static void ResetDragDrop()
{
IsDragging = false;
popup.IsOpen = false;
dataGrid.IsReadOnly = false;
}
/// <summary>
/// Updates the popup's position in case of a drag/drop operation.
/// </summary>
private static void OnMouseMove(object sender, MouseEventArgs e)
{
if (!IsDragging || e.LeftButton != MouseButtonState.Pressed) return;
//display the popup if it hasn't been opened yet
if (!popup.IsOpen)
{
//switch to read-only mode
dataGrid.IsReadOnly = true;
//make sure the popup is visible
popup.IsOpen = true;
}
Size popupSize = new Size(popup.ActualWidth, popup.ActualHeight);
popup.PlacementRectangle = new Rect(e.GetPosition(dataGrid), popupSize);
//make sure the row under the grid is being selected
Point position = e.GetPosition(dataGrid);
var row = UIHelpers.TryFindFromPoint<DataGridRow>(dataGrid, position);
if (row != null) dataGrid.SelectedItem = row.Item;
}
}
/// ///与UI相关的辅助方法。 /// public static class UIHelpers {
#region find parent
/// <summary>
/// Finds a parent of a given item on the visual tree.
/// </summary>
/// <typeparam name="T">The type of the queried item.</typeparam>
/// <param name="child">A direct or indirect child of the
/// queried item.</param>
/// <returns>The first parent item that matches the submitted
/// type parameter. If not matching item can be found, a null
/// reference is being returned.</returns>
public static T TryFindParent<T>(DependencyObject child)
where T : DependencyObject
{
//get parent item
DependencyObject parentObject = GetParentObject(child);
//we've reached the end of the tree
if (parentObject == null) return null;
//check if the parent matches the type we're looking for
T parent = parentObject as T;
if (parent != null)
{
return parent;
}
else
{
//use recursion to proceed with next level
return TryFindParent<T>(parentObject);
}
}
/// <summary>
/// This method is an alternative to WPF's
/// <see cref="VisualTreeHelper.GetParent"/> method, which also
/// supports content elements. Do note, that for content element,
/// this method falls back to the logical tree of the element.
/// </summary>
/// <param name="child">The item to be processed.</param>
/// <returns>The submitted item's parent, if available. Otherwise
/// null.</returns>
public static DependencyObject GetParentObject(DependencyObject child)
{
if (child == null) return null;
ContentElement contentElement = child as ContentElement;
if (contentElement != null)
{
DependencyObject parent = ContentOperations.GetParent(contentElement);
if (parent != null) return parent;
FrameworkContentElement fce = contentElement as FrameworkContentElement;
return fce != null ? fce.Parent : null;
}
//if it's not a ContentElement, rely on VisualTreeHelper
return VisualTreeHelper.GetParent(child);
}
#endregion
#region update binding sources
/// <summary>
/// Recursively processes a given dependency object and all its
/// children, and updates sources of all objects that use a
/// binding expression on a given property.
/// </summary>
/// <param name="obj">The dependency object that marks a starting
/// point. This could be a dialog window or a panel control that
/// hosts bound controls.</param>
/// <param name="properties">The properties to be updated if
/// <paramref name="obj"/> or one of its childs provide it along
/// with a binding expression.</param>
public static void UpdateBindingSources(DependencyObject obj,
params DependencyProperty[] properties)
{
foreach (DependencyProperty depProperty in properties)
{
//check whether the submitted object provides a bound property
//that matches the property parameters
BindingExpression be = BindingOperations.GetBindingExpression(obj, depProperty);
if (be != null) be.UpdateSource();
}
int count = VisualTreeHelper.GetChildrenCount(obj);
for (int i = 0; i < count; i++)
{
//process child items recursively
DependencyObject childObject = VisualTreeHelper.GetChild(obj, i);
UpdateBindingSources(childObject, properties);
}
}
#endregion
/// <summary>
/// Tries to locate a given item within the visual tree,
/// starting with the dependency object at a given position.
/// </summary>
/// <typeparam name="T">The type of the element to be found
/// on the visual tree of the element at the given location.</typeparam>
/// <param name="reference">The main element which is used to perform
/// hit testing.</param>
/// <param name="point">The position to be evaluated on the origin.</param>
public static T TryFindFromPoint<T>(UIElement reference, Point point)
where T : DependencyObject
{
DependencyObject element = reference.InputHitTest(point)
as DependencyObject;
if (element == null) return null;
else if (element is T) return (T)element;
else return TryFindParent<T>(element);
}
}
问题是当我按下一行来拖动它时，不会调用事件OnMouseLeftButtonDown ...但在此之后调用OnMouseLeftButtonUp ....
有没有办法做到这一点......
我似乎找不到方法
答案 0 :(得分：8)
最后我得到了问题，并为此做了一些改变才能正常工作
我使用this示例让Drag Drop Logic amd使得这种行为可能对其他人有用......请提出改进建议我很乐意改变......
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using Microsoft.Windows.Controls;
using System.Windows.Input;
using System.Collections;
namespace DataGridDragAndDrop
{
public static class DragDropRowBehavior
{
private static DataGrid dataGrid;
private static Popup popup;
private static bool enable;
private static object draggedItem;
public static object DraggedItem
{
get { return DragDropRowBehavior.draggedItem; }
set { DragDropRowBehavior.draggedItem = value; }
}
public static Popup GetPopupControl(DependencyObject obj)
{
return (Popup)obj.GetValue(PopupControlProperty);
}
public static void SetPopupControl(DependencyObject obj, Popup value)
{
obj.SetValue(PopupControlProperty, value);
}
// Using a DependencyProperty as the backing store for PopupControl. This enables animation, styling, binding, etc...
public static readonly DependencyProperty PopupControlProperty =
DependencyProperty.RegisterAttached("PopupControl", typeof(Popup), typeof(DragDropRowBehavior), new UIPropertyMetadata(null, OnPopupControlChanged));
private static void OnPopupControlChanged(DependencyObject depObject, DependencyPropertyChangedEventArgs e)
{
if (e.NewValue == null || !(e.NewValue is Popup))
{
throw new ArgumentException("Popup Control should be set", "PopupControl");
}
popup = e.NewValue as Popup;
dataGrid = depObject as DataGrid;
// Check if DataGrid
if (dataGrid == null)
return;
if (enable && popup != null)
{
dataGrid.BeginningEdit += new EventHandler<DataGridBeginningEditEventArgs>(OnBeginEdit);
dataGrid.CellEditEnding += new EventHandler<DataGridCellEditEndingEventArgs>(OnEndEdit);
dataGrid.MouseLeftButtonUp += new System.Windows.Input.MouseButtonEventHandler(OnMouseLeftButtonUp);
dataGrid.PreviewMouseLeftButtonDown += new MouseButtonEventHandler(OnMouseLeftButtonDown);
dataGrid.MouseMove += new MouseEventHandler(OnMouseMove);
}
else
{
dataGrid.BeginningEdit -= new EventHandler<DataGridBeginningEditEventArgs>(OnBeginEdit);
dataGrid.CellEditEnding -= new EventHandler<DataGridCellEditEndingEventArgs>(OnEndEdit);
dataGrid.MouseLeftButtonUp -= new System.Windows.Input.MouseButtonEventHandler(OnMouseLeftButtonUp);
dataGrid.MouseLeftButtonDown -= new MouseButtonEventHandler(OnMouseLeftButtonDown);
dataGrid.MouseMove -= new MouseEventHandler(OnMouseMove);
dataGrid = null;
popup = null;
draggedItem = null;
IsEditing = false;
IsDragging = false;
}
}
public static bool GetEnabled(DependencyObject obj)
{
return (bool)obj.GetValue(EnabledProperty);
}
public static void SetEnabled(DependencyObject obj, bool value)
{
obj.SetValue(EnabledProperty, value);
}
// Using a DependencyProperty as the backing store for Enabled. This enables animation, styling, binding, etc...
public static readonly DependencyProperty EnabledProperty =
DependencyProperty.RegisterAttached("Enabled", typeof(bool), typeof(DragDropRowBehavior), new UIPropertyMetadata(false,OnEnabledChanged));
private static void OnEnabledChanged(DependencyObject depObject,DependencyPropertyChangedEventArgs e)
{
//Check if value is a Boolean Type
if (e.NewValue is bool == false)
throw new ArgumentException("Value should be of bool type", "Enabled");
enable = (bool)e.NewValue;
}
public static bool IsEditing { get; set; }
public static bool IsDragging { get; set; }
private static void OnBeginEdit(object sender, DataGridBeginningEditEventArgs e)
{
IsEditing = true;
//in case we are in the middle of a drag/drop operation, cancel it...
if (IsDragging) ResetDragDrop();
}
private static void OnEndEdit(object sender, DataGridCellEditEndingEventArgs e)
{
IsEditing = false;
}
/// <summary>
/// Initiates a drag action if the grid is not in edit mode.
/// </summary>
private static void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
if (IsEditing) return;
var row = UIHelpers.TryFindFromPoint<DataGridRow>((UIElement)sender, e.GetPosition(dataGrid));
if (row == null || row.IsEditing) return;
//set flag that indicates we're capturing mouse movements
IsDragging = true;
DraggedItem = row.Item;
}
/// <summary>
/// Completes a drag/drop operation.
/// </summary>
private static void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
if (!IsDragging || IsEditing)
{
return;
}
//get the target item
var targetItem = dataGrid.SelectedItem;
if (targetItem == null || !ReferenceEquals(DraggedItem, targetItem))
{
//get target index
var targetIndex = ((dataGrid).ItemsSource as IList).IndexOf(targetItem);
//remove the source from the list
((dataGrid).ItemsSource as IList).Remove(DraggedItem);
//move source at the target's location
((dataGrid).ItemsSource as IList).Insert(targetIndex, DraggedItem);
//select the dropped item
dataGrid.SelectedItem = DraggedItem;
}
//reset
ResetDragDrop();
}
/// <summary>
/// Closes the popup and resets the
/// grid to read-enabled mode.
/// </summary>
private static void ResetDragDrop()
{
IsDragging = false;
popup.IsOpen = false;
dataGrid.IsReadOnly = false;
}
/// <summary>
/// Updates the popup's position in case of a drag/drop operation.
/// </summary>
private static void OnMouseMove(object sender, MouseEventArgs e)
{
if (!IsDragging || e.LeftButton != MouseButtonState.Pressed) return;
popup.DataContext = DraggedItem;
//display the popup if it hasn't been opened yet
if (!popup.IsOpen)
{
//switch to read-only mode
dataGrid.IsReadOnly = true;
//make sure the popup is visible
popup.IsOpen = true;
}
Size popupSize = new Size(popup.ActualWidth, popup.ActualHeight);
popup.PlacementRectangle = new Rect(e.GetPosition(dataGrid), popupSize);
//make sure the row under the grid is being selected
Point position = e.GetPosition(dataGrid);
var row = UIHelpers.TryFindFromPoint<DataGridRow>(dataGrid, position);
if (row != null) dataGrid.SelectedItem = row.Item;
}
}
}
public static class UIHelpers
{
#region find parent
/// <summary>
/// Finds a parent of a given item on the visual tree.
/// </summary>
/// <typeparam name="T">The type of the queried item.</typeparam>
/// <param name="child">A direct or indirect child of the
/// queried item.</param>
/// <returns>The first parent item that matches the submitted
/// type parameter. If not matching item can be found, a null
/// reference is being returned.</returns>
public static T TryFindParent<T>(DependencyObject child)
where T : DependencyObject
{
//get parent item
DependencyObject parentObject = GetParentObject(child);
//we've reached the end of the tree
if (parentObject == null) return null;
//check if the parent matches the type we're looking for
T parent = parentObject as T;
if (parent != null)
{
return parent;
}
else
{
//use recursion to proceed with next level
return TryFindParent<T>(parentObject);
}
}
/// <summary>
/// This method is an alternative to WPF's
/// <see cref="VisualTreeHelper.GetParent"/> method, which also
/// supports content elements. Do note, that for content element,
/// this method falls back to the logical tree of the element.
/// </summary>
/// <param name="child">The item to be processed.</param>
/// <returns>The submitted item's parent, if available. Otherwise
/// null.</returns>
public static DependencyObject GetParentObject(DependencyObject child)
{
if (child == null) return null;
ContentElement contentElement = child as ContentElement;
if (contentElement != null)
{
DependencyObject parent = ContentOperations.GetParent(contentElement);
if (parent != null) return parent;
FrameworkContentElement fce = contentElement as FrameworkContentElement;
return fce != null ? fce.Parent : null;
}
//if it's not a ContentElement, rely on VisualTreeHelper
return VisualTreeHelper.GetParent(child);
}
#endregion
#region update binding sources
/// <summary>
/// Recursively processes a given dependency object and all its
/// children, and updates sources of all objects that use a
/// binding expression on a given property.
/// </summary>
/// <param name="obj">The dependency object that marks a starting
/// point. This could be a dialog window or a panel control that
/// hosts bound controls.</param>
/// <param name="properties">The properties to be updated if
/// <paramref name="obj"/> or one of its childs provide it along
/// with a binding expression.</param>
public static void UpdateBindingSources(DependencyObject obj,
params DependencyProperty[] properties)
{
foreach (DependencyProperty depProperty in properties)
{
//check whether the submitted object provides a bound property
//that matches the property parameters
BindingExpression be = BindingOperations.GetBindingExpression(obj, depProperty);
if (be != null) be.UpdateSource();
}
int count = VisualTreeHelper.GetChildrenCount(obj);
for (int i = 0; i < count; i++)
{
//process child items recursively
DependencyObject childObject = VisualTreeHelper.GetChild(obj, i);
UpdateBindingSources(childObject, properties);
}
}
#endregion
/// <summary>
/// Tries to locate a given item within the visual tree,
/// starting with the dependency object at a given position.
/// </summary>
/// <typeparam name="T">The type of the element to be found
/// on the visual tree of the element at the given location.</typeparam>
/// <param name="reference">The main element which is used to perform
/// hit testing.</param>
/// <param name="point">The position to be evaluated on the origin.</param>
public static T TryFindFromPoint<T>(UIElement reference, Point point)
where T : DependencyObject
{
DependencyObject element = reference.InputHitTest(point)
as DependencyObject;
if (element == null) return null;
else if (element is T) return (T)element;
else return TryFindParent<T>(element);
}
}
<!-- Drag and Drop Popup -->
<Popup x:Name="popup1"
AllowsTransparency="True"
IsHitTestVisible="False"
Placement="RelativePoint"
PlacementTarget="{Binding ElementName=shareGrid}">
<!-- Your own Popup construction Use properties of DraggedObject inside for Binding -->
<TextBlock Margin="8,0,0,0"
VerticalAlignment="Center"
FontSize="14"
FontWeight="Bold"
<!-- I used name property of in my Dragged row -->
Text="{Binding Path=Name}" />
</Popup>
<DataGrid x:Name="myDataGrid"
AutoGenerateColumns="False"
CanUserAddRows="False"
CanUserDeleteRows="False"
CanUserReorderColumns="False"
CanUserSortColumns="False"
ItemsSource="{Binding}"
SelectionMode="Single"
this:DragDropRowBehavior.Enabled="True"
this:DragDropRowBehavior.PopupControl="{Binding ElementName=popup1}"></DataGrid >
答案 1 :(得分：1)
如果未在所需对象上触发事件，则是因为某些其他控件正在“吞咽”它。尝试使用OnPreviewMouseLeftButtonDown。如果预览没有显示事件，请尝试将该预览方法移动到父类。
答案 2 :(得分：0)
我用@Dave解决方案创建了一个行为：
public class DragDropRowBehavior : Behavior<DataGrid>
{
private object draggedItem;
private bool isEditing;
private bool isDragging;
#region DragEnded
public static readonly RoutedEvent DragEndedEvent =
EventManager.RegisterRoutedEvent("DragEnded", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(DragDropRowBehavior));
public static void AddDragEndedHandler(DependencyObject d, RoutedEventHandler handler)
{
UIElement uie = d as UIElement;
if (uie != null)
uie.AddHandler(DragDropRowBehavior.DragEndedEvent, handler);
}
public static void RemoveDragEndedHandler(DependencyObject d, RoutedEventHandler handler)
{
UIElement uie = d as UIElement;
if (uie != null)
uie.RemoveHandler(DragDropRowBehavior.DragEndedEvent, handler);
}
private void RaiseDragEndedEvent()
{
var args = new RoutedEventArgs(DragDropRowBehavior.DragEndedEvent);
AssociatedObject.RaiseEvent(args);
}
#endregion
#region Popup
public static readonly DependencyProperty PopupProperty =
DependencyProperty.Register("Popup", typeof(System.Windows.Controls.Primitives.Popup), typeof(DragDropRowBehavior));
public System.Windows.Controls.Primitives.Popup Popup
{
get { return (System.Windows.Controls.Primitives.Popup)GetValue(PopupProperty); }
set { SetValue(PopupProperty, value); }
}
#endregion
protected override void OnAttached()
{
base.OnAttached();
AssociatedObject.BeginningEdit += OnBeginEdit;
AssociatedObject.CellEditEnding += OnEndEdit;
AssociatedObject.MouseLeftButtonUp += OnMouseLeftButtonUp;
AssociatedObject.PreviewMouseLeftButtonDown += OnMouseLeftButtonDown;
AssociatedObject.MouseMove += OnMouseMove;
}
protected override void OnDetaching()
{
base.OnDetaching();
AssociatedObject.BeginningEdit -= OnBeginEdit;
AssociatedObject.CellEditEnding -= OnEndEdit;
AssociatedObject.MouseLeftButtonUp -= OnMouseLeftButtonUp;
AssociatedObject.MouseLeftButtonDown -= OnMouseLeftButtonDown;
AssociatedObject.MouseMove -= OnMouseMove;
Popup = null;
draggedItem = null;
isEditing = false;
isDragging = false;
}
private void OnBeginEdit(object sender, DataGridBeginningEditEventArgs e)
{
isEditing = true;
//in case we are in the middle of a drag/drop operation, cancel it...
if (isDragging) ResetDragDrop();
}
private void OnEndEdit(object sender, DataGridCellEditEndingEventArgs e)
{
isEditing = false;
}
private void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
if (isEditing) return;
var row = UIHelpers.TryFindFromPoint<DataGridRow>((UIElement)sender, e.GetPosition(AssociatedObject));
if (row == null || row.IsEditing) return;
//set flag that indicates we're capturing mouse movements
isDragging = true;
draggedItem = row.Item;
}
private void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
if (!isDragging || isEditing)
return;
//get the target item
var targetItem = AssociatedObject.SelectedItem;
if (targetItem == null || !ReferenceEquals(draggedItem, targetItem))
{
//get target index
var targetIndex = ((AssociatedObject).ItemsSource as IList).IndexOf(targetItem);
//remove the source from the list
((AssociatedObject).ItemsSource as IList).Remove(draggedItem);
//move source at the target's location
((AssociatedObject).ItemsSource as IList).Insert(targetIndex, draggedItem);
//select the dropped item
AssociatedObject.SelectedItem = draggedItem;
RaiseDragEndedEvent();
}
//reset
ResetDragDrop();
}
private void ResetDragDrop()
{
isDragging = false;
Popup.IsOpen = false;
AssociatedObject.IsReadOnly = false;
}
private void OnMouseMove(object sender, MouseEventArgs e)
{
if (!isDragging || e.LeftButton != MouseButtonState.Pressed)
return;
Popup.DataContext = draggedItem;
//display the popup if it hasn't been opened yet
if (!Popup.IsOpen)
{
//switch to read-only mode
AssociatedObject.IsReadOnly = true;
//make sure the popup is visible
Popup.IsOpen = true;
}
var popupSize = new Size(Popup.ActualWidth, Popup.ActualHeight);
Popup.PlacementRectangle = new Rect(e.GetPosition(AssociatedObject), popupSize);
//make sure the row under the grid is being selected
var position = e.GetPosition(AssociatedObject);
var row = UIHelpers.TryFindFromPoint<DataGridRow>(AssociatedObject, position);
if (row != null) AssociatedObject.SelectedItem = row.Item;
}
}
希望它能帮助未来的用户：）