// проверка: находится ли узел связи впределах прямоугольника
public static Boolean InArea(IDrag element, Rectangle rect)
{
if ((element.Location.X <= rect.X + rect.Width) && (element.Location.X >= rect.X) &&
(element.Location.Y >= rect.Y) && (element.Location.Y <= rect.Y + rect.Height))
return true;
return false;
}
public override UIView HitTest(CoreGraphics.CGPoint point, UIEvent uievent)
{
UIView hitTestView = base.HitTest(point, uievent);
if (LayoutElement.GestureEnabled)
{
foreach (var child in LayoutElement.Children)
{
if (child.Bounds.Contains((double)point.X, (double)point.Y))
{
var draggable = child as IDrag;
if (draggable != null && draggable.DragEnabled)
{
lastTouchX = point.X;
lastTouchY = point.Y;
dragMightStart = true;
currentDraggable = draggable;
return(this);
}
}
}
}
return(hitTestView);
}
public void OnDraggableRemoved(IDrag draggable)
{
//System.Diagnostics.Debug.WriteLine("Box {0} OnDraggableRemoved", Date.ToString("d"));
DraggableChildren.Remove(draggable);
Status = DroppableState.Accepting;
Debug.WriteLine("RemovedChildren" + DraggableChildren.Count);
}
public async void StopDragging()
{
_currDraggableWidth = -1;
_currDraggableHeight = -1;
foreach (var child in DraggableChildren)
{
IDrop target;
//System.Diagnostics.Debug.WriteLine("Child.Status = {0}", child.Status);
if (child.Status == DragState.Running || child.Status == DragState.Started)
{
//System.Diagnostics.Debug.WriteLine("child is running, see if there's a droppable target nearby");
if (MatchNearby(child, out target) && target.DropEnabled)
{
//System.Diagnostics.Debug.WriteLine("\tfound");
child.OnDragCompleted(target);
target.OnDraggableDropped(child);
}
else
{
//System.Diagnostics.Debug.WriteLine("\tnot found");
child.OnDragAborted();
}
}
}
await Task.Delay(10); // allow changes to propagate (esp on Android)
// where lack of a delay caused the draggable to be removed as soon as it was dropped
// check the droppables
foreach (var child in DroppableChildren)
{
if (child.DraggableChildren != null && child.DraggableChildren.Count > 0)
{
// check if draggable still within bounds
var view = child as View;
bool draggableRemoved = false;
IDrag draggableChild = null;
foreach (var drag in child.DraggableChildren)
{
//System.Diagnostics.Debug.WriteLine("{0}\t{1}", view.Bounds, drag.CurrentBounds);
if (view != null && !view.Bounds.Contains((drag).CurrentBounds.Center))
{
draggableChild = drag;
draggableRemoved = true;
}
}
if (draggableRemoved)
{
child.OnDraggableRemoved(draggableChild);
}
}
}
this.InvalidateLayout();
}
/// <summary>
/// Drag in canvas
/// </summary>
/// <param name="dragTarget">drag target</param>
/// <param name="dragElement">drag element</param>
/// <param name="bound">bound</param>
/// <returns></returns>
public static bool BindDrag(this FrameworkElement dragTarget, FrameworkElement dragElement, DragBound bound, Action <Point, bool> positonChangeCallback = null)
{
bool result = false;
if (dragTarget.Parent != null && (dragTarget.Parent as Canvas) != null)
{
Canvas moveCvs = dragTarget.Parent as Canvas;
Point positionOnElement = new Point();
bool isDrag = false;
int deviceId = 0;
DragBoundCheck check = new DragBoundCheck(dragTarget, bound);
dragElement.PreviewTouchDown += delegate(object sender, TouchEventArgs e)
{
IDrag dragObj = dragTarget as IDrag;
if (dragObj != null && dragObj.IsDrag == false)
{
return;
}
if (isDrag == false)
{
deviceId = e.TouchDevice.Id;
positionOnElement = e.GetTouchPoint(dragTarget).Position;
isDrag = true;
dragElement.CaptureTouch(e.TouchDevice);
}
};
dragElement.PreviewTouchMove += delegate(object sender, TouchEventArgs e)
{
if (isDrag && e.TouchDevice.Id == deviceId)
{
SetNewMovPosition(dragTarget, positonChangeCallback, moveCvs, positionOnElement, false, e);
}
};
dragElement.PreviewTouchUp += delegate(object sender, TouchEventArgs e)
{
if (isDrag && deviceId == e.TouchDevice.Id)
{
isDrag = false;
SetNewMovPosition(dragTarget, positonChangeCallback, moveCvs, positionOnElement, true, e);
dragElement.ReleaseTouchCapture(e.TouchDevice);
}
};
result = true;
}
return(result);
}
public void OnDraggableDropped(IDrag draggable)
{
//System.Diagnostics.Debug.WriteLine("Box {0} OnDraggableDropped", Date.ToString("d"));
this.Scale = 1;
if (DraggableChildren == null)
{
DraggableChildren = new List <IDrag>();
}
DraggableChildren.Add(draggable);
Status = DroppableState.Accepting;
Debug.WriteLine("DraggableChildren: " + DraggableChildren.Count);
}
public override bool OnTouchEvent(Android.Views.MotionEvent e)
{
double x = (e.GetX() * LayoutElement.Width) / this.Width;
double y = (e.GetY() * LayoutElement.Height) / this.Height;
switch (e.Action)
{
case Android.Views.MotionEventActions.Down:
HandleTouchStart(x, y);
startX = x;
startY = y;
break;
case Android.Views.MotionEventActions.Move:
if (LayoutElement.Dragging)
{
LayoutElement.HandleTouch(x, y);
}
break;
case Android.Views.MotionEventActions.Up:
if (currentDraggable != null && ((currentDraggable.Status == DragState.None || currentDraggable.Status == DragState.Started) || BelowTapThreshold(x, y)))
{
if (currentDraggable.TapEnabled)
{
currentDraggable.OnTapped();
}
currentDraggable = null;
}
if (LayoutElement.Dragging)
{
MessagingCenter.Send <DragAndDropLayoutRenderer, bool>(this, "IsDragging", false);
LayoutElement.StopDragging();
LayoutElement.Dragging = false;
currentDraggable = null;
}
break;
default:
break;
}
return(true);
}
public static Point CheckElementPosition(IDrag element, Int32 width, Int32 height)
{
Int32 i_x;
Int32 i_y;
Int32 x = i_x = element.Location.X;
Int32 y = i_y = element.Location.Y;
if (i_x > width)
x = width - Drawing.xOffset;
else if (i_x < 0)
x = Drawing.xOffset;
if (i_y > height)
y = height - Drawing.yOffset;
else if (i_y < 0)
y = Drawing.yOffset;
return new Point(x, y);
}
public override bool OnInterceptTouchEvent(Android.Views.MotionEvent ev)
{
if (!LayoutElement.GestureEnabled)
{
return(false);
}
double x = (ev.GetX() * LayoutElement.Width) / this.Width;
double y = (ev.GetY() * LayoutElement.Height) / this.Height;
IDrag draggable;
if (LayoutElement.IDragTouched(x, y, out draggable))
{
currentDraggable = draggable;
return(true);
}
return(false);
}
public override void TouchesEnded(Foundation.NSSet touches, UIEvent evt)
{
base.TouchesEnded(touches, evt);
if (currentDraggable != null && (currentDraggable.Status == DragState.None || currentDraggable.Status == DragState.Started))
{
if (currentDraggable.TapEnabled)
{
currentDraggable.OnTapped();
}
currentDraggable = null;
}
if (LayoutElement.Dragging)
{
LayoutElement.StopDragging();
LayoutElement.Dragging = false;
dragMightStart = false;
currentDraggable = null;
}
}
public bool IDragTouched(double x, double y, out IDrag draggable)
{
draggable = null;
foreach (var child in DraggableChildren)
{
if (!child.DragEnabled)
{
continue;
}
var view = child as View;
if (view.Bounds.Contains(x, y))
{
draggable = child;
if (draggable != null)
{
return(true);
}
}
}
return(false);
}
bool MatchNearby(IDrag child, out IDrop container)
{
var view = child as View;
container = null;
if (child.TargetType == null || DroppableChildren.Count == 0)
{
return(false);
}
//find all possible targets
var targetCandidates = DroppableChildren.FindAll((t) => {
var v = t as View;
bool near = v.Bounds.IntersectsWith(view.Bounds);
return(t.GetType() == child.TargetType && near && t.DropEnabled);
});
if (targetCandidates.Count == 0)
{
return(false);
}
// find the match which *contains* the draggable
foreach (var target in targetCandidates)
{
container = target as IDrop;
var targetView = target as View;
if (targetView.Bounds.Contains(view.Bounds.Center))
{
return(true);
}
}
// otherwise return the first one that intersects it
container = targetCandidates[0] as IDrop;
return(true);
}
