/// <summary>
/// 执行拖拽操作，在进行了有效的拖拽操作时执行
/// </summary>
/// <param name="dragItem"></param>
/// <param name="adornerSource"></param>
private void DoDragDrop(object dragItem, UIElement adornerSource)
{
if (adornerSource != null) //如果选中按钮不为空
{
var rect = VisualTreeHelper.GetDescendantBounds(adornerSource); //获取拖拽节点的外边框
var size = new Size((double)Math.Ceiling(rect.Width), (double)Math.Ceiling(rect.Height)); //获取比节点大的整数值边框
var brush = new VisualBrush(adornerSource); //初始化包含节点的VisualBrush
_adorner = new DragDropAdorner(_dragScope, size, brush); //新建拖拽装饰器
_adorner.Opacity = 0.7;
_adorner.Visibility = Visibility.Hidden;
}
DragDrop.AddPreviewDragEnterHandler(_dragScope, _dragEnter);
DragDrop.AddPreviewDragOverHandler(_dragScope, _dragOver);
DragDrop.AddPreviewDragLeaveHandler(_dragScope, _dragLeave);
DragDrop.DoDragDrop(_source, dragItem, DragDropEffects.All); //执行拖拽方法，该方法会在拖拽结束后结束并返回
DragFinished(); //执行拖拽结束方法
DragDrop.RemovePreviewDragEnterHandler(_dragScope, _dragEnter);
DragDrop.RemovePreviewDragOverHandler(_dragScope, _dragOver);
DragDrop.RemovePreviewDragLeaveHandler(_dragScope, _dragLeave);
}
private void DoDragDrop(object dragItem, UIElement adornerSource)
{
if (adornerSource != null)
{
var rect = VisualTreeHelper.GetDescendantBounds(adornerSource);
var size = new Size((double)Math.Ceiling(rect.Width), (double)Math.Ceiling(rect.Height));
var brush = new VisualBrush(adornerSource);
_adorner = new DragDropAdorner(_dragScope, size, brush);
_adorner.Opacity = 0.7;
_adorner.Visibility = Visibility.Hidden;
}
DragDrop.AddPreviewDragEnterHandler(_dragScope, _dragEnter);
DragDrop.AddPreviewDragOverHandler(_dragScope, _dragOver);
DragDrop.AddPreviewDragLeaveHandler(_dragScope, _dragLeave);
var resultEffects = DragDrop.DoDragDrop(_source, dragItem, DragDropEffects.All);
DragFinished(resultEffects);
DragDrop.RemovePreviewDragEnterHandler(_dragScope, _dragEnter);
DragDrop.RemovePreviewDragOverHandler(_dragScope, _dragOver);
DragDrop.RemovePreviewDragLeaveHandler(_dragScope, _dragLeave);
}
private void StartDrag(MouseEventArgs args)
{
IDataObject data = null;
UIElement dragelement = null;
// ADD THE DATA
if (this.Callback != null)
{
DragDataWrapper dw = new DragDataWrapper();
data = new DataObject(typeof(DragDataWrapper).ToString(), dw);
if ((this.Callback.SupportedActions & DragDropProviderActions.MultiFormatData) != 0)
{
this.Callback.AppendData(ref data, args);
}
if ((this.Callback.SupportedActions & DragDropProviderActions.Data) != 0)
{
dw.Data = this.Callback.GetData();
}
if ((this.Callback.SupportedActions & DragDropProviderActions.Visual) != 0)
{
dragelement = this.Callback.GetVisual(args);
}
else
{
dragelement = args.OriginalSource as UIElement;
}
dw.Source = this.DragSource;
dw.Shim = this.Callback;
Debug.Assert(this.DragScope == null, "The DragDataWrapper is meant for in-proc... Sorry for asserting, just wanted to confirm.. comment out assertion if needed");
}
else
{
dragelement = args.OriginalSource as UIElement;
data = new DataObject(typeof(UIElement).ToString(), dragelement);
}
if (dragelement == null || data == null || dragelement == this.DragSource)
{
return;
}
DragEventHandler dragOver = null;
DragEventHandler dragLeave = null;
QueryContinueDragEventHandler queryContinue = null;
GiveFeedbackEventHandler giveFeedback = null;
DragDropEffects effects = this.GetDragDropEffects();
DragDropEffects resultEffects;
// Inprocess Drag ...
if (this.DragScope != null)
{
bool previousAllowDrop = this.DragScope.AllowDrop;
this.adorner = new DragAdorner(this.DragScope, (UIElement)dragelement, true, this.Opacity);
this.layer = AdornerLayer.GetAdornerLayer(this.DragScope as Visual);
this.layer.Add(this.adorner);
if (this.DragScope != this.DragSource)
{
this.DragScope.AllowDrop = true;
DragDrop.AddPreviewDragOverHandler((DependencyObject)this.DragScope, dragOver = new DragEventHandler(DragScope_DragOver));
DragDrop.AddPreviewDragLeaveHandler(this.DragScope, dragLeave = new DragEventHandler(DragScope_DragLeave));
DragDrop.AddPreviewQueryContinueDragHandler(this.DragSource, queryContinue = new QueryContinueDragEventHandler(OnQueryContinueDrag));
}
try
{
this.IsDragging = true;
this.mouseLeftScope = false;
resultEffects = DragDrop.DoDragDrop(this.DragSource, data, effects);
this.DragFinished(resultEffects);
}
catch
{
Debug.Assert(false);
}
if (this.DragScope != this.DragSource)
{
this.DragScope.AllowDrop = previousAllowDrop;
DragDrop.RemovePreviewDragOverHandler(this.DragScope, dragOver);
DragDrop.RemovePreviewDragLeaveHandler(this.DragScope, dragLeave);
DragDrop.RemovePreviewQueryContinueDragHandler(this.DragSource, queryContinue);
}
}
else
{
DragDrop.AddPreviewQueryContinueDragHandler(this.DragSource, queryContinue = new QueryContinueDragEventHandler(OnQueryContinueDrag));
DragDrop.AddGiveFeedbackHandler(this.DragSource, giveFeedback = new GiveFeedbackEventHandler(OnGiveFeedback));
this.IsDragging = true;
if ((this.Callback.SupportedActions & DragDropProviderActions.Visual) != 0)
{
this.CreateDragDropWindow(dragelement);
this.dragdropWindow.Show();
}
try
{
resultEffects = DragDrop.DoDragDrop(this.DragSource, data, effects);
}
finally
{
}
if ((this.Callback.SupportedActions & DragDropProviderActions.Visual) != 0)
{
this.DestroyDragDropWindow();
}
DragDrop.RemovePreviewQueryContinueDragHandler(this.DragSource, OnQueryContinueDrag);
DragDrop.AddGiveFeedbackHandler(this.DragSource, OnGiveFeedback);
this.IsDragging = false;
this.DragFinished(resultEffects);
}
}
void StartDrag(MouseEventArgs args)
{
IDataObject data = null;
UIElement dragelement = null;
// ADD THE DATA
if (_callback != null)
{
DragDataWrapper dw = new DragDataWrapper();
data = new DataObject(typeof(DragDataWrapper).ToString(), dw);
if ((_callback.SupportedActions & DragDropProviderActions.MultiFormatData) != 0)
{
_callback.AppendData(ref data, args);
}
if ((_callback.SupportedActions & DragDropProviderActions.Data) != 0)
{
dw.Data = _callback.GetData();
}
if ((_callback.SupportedActions & DragDropProviderActions.Visual) != 0)
{
dragelement = _callback.GetVisual(args);
}
else
{
dragelement = args.OriginalSource as UIElement;
}
dw.Source = _dragSource;
dw.Shim = _callback;
// System.Diagnostics.Debug.Assert(DragScope == null, "The DragDataWrapper is meant for in-proc... Sorry for asserting, just wanted to confirm.. comment out assertion if needed");
}
else
{
dragelement = args.OriginalSource as UIElement;
data = new DataObject(typeof(UIElement).ToString(), dragelement);
}
if (dragelement == null || data == null || dragelement == this._dragSource)
{
return;
}
#if DEBUG
// Add it as Text ... good for testing purposes
if (!data.GetDataPresent(DataFormats.Text))
{
data.SetData(DataFormats.Text, "abcd");
}
#endif
DragEventHandler dragOver = null;
DragEventHandler dragLeave = null;
QueryContinueDragEventHandler queryContinue = null;
GiveFeedbackEventHandler giveFeedback = null;
DragDropEffects effects = GetDragDropEffects();
DragDropEffects resultEffects;
// Inprocess Drag ...
if (DragScope != null)
{
bool previousAllowDrop = DragScope.AllowDrop;
_adorner = new DragAdorner(DragScope, (UIElement)dragelement, true, Opacity);
_layer = AdornerLayer.GetAdornerLayer(DragScope as Visual);
_layer.Add(_adorner);
if (DragScope != _dragSource)
{
DragScope.AllowDrop = true;
DragDrop.AddPreviewDragOverHandler((DependencyObject)DragScope, dragOver = new DragEventHandler(DragScope_DragOver));
DragDrop.AddPreviewDragLeaveHandler(DragScope, dragLeave = new DragEventHandler(DragScope_DragLeave));
DragDrop.AddPreviewQueryContinueDragHandler(_dragSource, queryContinue = new QueryContinueDragEventHandler(onQueryContinueDrag));
}
try
{
IsDragging = true;
this._mouseLeftScope = false;
resultEffects = DragDrop.DoDragDrop(_dragSource, data, effects);
DragFinished(resultEffects);
}
catch
{
System.Diagnostics.Debug.Assert(false);
}
if (DragScope != _dragSource)
{
DragScope.AllowDrop = previousAllowDrop;
DragDrop.RemovePreviewDragOverHandler(DragScope, dragOver);
DragDrop.RemovePreviewDragLeaveHandler(DragScope, dragLeave);
DragDrop.RemovePreviewQueryContinueDragHandler(_dragSource, queryContinue);
}
}
else
{
DragDrop.AddPreviewQueryContinueDragHandler(_dragSource, queryContinue = new QueryContinueDragEventHandler(onQueryContinueDrag));
DragDrop.AddGiveFeedbackHandler(_dragSource, giveFeedback = new GiveFeedbackEventHandler(onGiveFeedback));
IsDragging = true;
CreateDragDropWindow(dragelement);
this._dragdropWindow.Show();
try
{
resultEffects = DragDrop.DoDragDrop(_dragSource, data, effects);
}
finally { }
DestroyDragDropWindow();
DragDrop.RemovePreviewQueryContinueDragHandler(_dragSource, onQueryContinueDrag);
DragDrop.AddGiveFeedbackHandler(_dragSource, onGiveFeedback);
IsDragging = false;
DragFinished(resultEffects);
}
}
