public UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
UIDropOperation operation = UIDropOperation.Cancel;
if (session.LocalDragSession == null)
{
return(new UIDropProposal(operation));
}
if (interaction.View is IVisualElementRenderer renderer)
{
DataPackage package = null;
if (session.LocalDragSession.Items.Length > 0 &&
session.LocalDragSession.Items[0].LocalObject is CustomLocalStateData cdi)
{
package = cdi.DataPackage;
}
if (HandleDragOver((View)renderer.Element, package))
{
operation = UIDropOperation.Copy;
}
}
return(new UIDropProposal(operation));
}
public override void SessionDidExit(UIDropInteraction interaction, IUIDropSession session)
{
Console.WriteLine($"SessionDidExit ({interaction}, {session})");
BeginInvokeOnMainThread(() => {
dropView.BackgroundColor = dropView.defaultColor;
});
}
public virtual void PerformDrop(UIDropInteraction interaction, IUIDropSession session)
{
if (PerformDropOperation == null)
{
throw new NullReferenceException("The PerformDropOperation delegate must be defined before calling the 'PerformDrop' method");
}
PerformDropOperation(interaction, session);
}
public UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
if (session.LocalDragSession == null)
{
return(new UIDropProposal(UIDropOperation.Forbidden));
}
return(new UIDropProposal(UIDropOperation.Move));
}
public override void SessionDidEnter(UIDropInteraction interaction, IUIDropSession session)
{
Console.WriteLine($"SessionDidEnter ({interaction}, {session})");
BeginInvokeOnMainThread(() => {
dropView.BackgroundColor = UIColor.Yellow;
});
}
public void PerformDrop(UIDropInteraction interaction, IUIDropSession session)
{
// Get the drag items (UIImage in this case).
session.LoadObjects <UIImage> (images => {
ImageView.Image = images?.First();
});
var dropLocation = session.LocationInView(View);
UpdateLayers(dropLocation);
}
public virtual UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
if (ResolveDropOperation == null)
{
throw new NullReferenceException("The ResolveDropOperation delegate must be defined before calling the 'SessionDidUpdate' method");
}
return(new UIDropProposal(ResolveDropOperation(this, interaction, session)));
}
public override void PerformDrop(UIDropInteraction interaction, IUIDropSession session)
{
Console.WriteLine($"PerformDrop ({interaction}, {session})");
INSItemProviderReading objectType = new StringReader();
session.Completion(objectType, (objects) => {
Console.WriteLine($"PerformDropCompletion ({objects.Length})");
dropView.BackgroundColor = UIColor.Green;
});
}
public UITargetedDragPreview GetPreviewForDroppingItem(UIDropInteraction interaction, UIDragItem item, UITargetedDragPreview defaultPreview)
{
if (item.LocalObject == null)
{
return(null);
}
else
{
DropPoint = defaultPreview.View.Center;
var target = new UIDragPreviewTarget(View, DropPoint); // HACK: why is this null?
//return defaultPreview.GetRetargetedPreview(target);
return(defaultPreview);
}
}
public void SessionDidExit(UIDropInteraction interaction, IUIDropSession session)
{
DataPackage package = null;
if (session.LocalDragSession.Items.Length > 0 &&
session.LocalDragSession.Items[0].LocalObject is CustomLocalStateData cdi)
{
package = cdi.DataPackage;
}
if (HandleDragLeave((View)_viewHandler.VirtualView, package))
{
}
}
public UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
UIDropOperation operation;
if (session.LocalDragSession == null)
{
operation = UIDropOperation.Copy;
}
else
{
operation = UIDropOperation.Move;
}
return(new UIDropProposal(operation));
}
public void PerformDrop(UIDropInteraction interaction, IUIDropSession session)
{
if (session.LocalDragSession == null)
{
return;
}
if (session.LocalDragSession.Items.Length > 0 &&
session.LocalDragSession.Items[0].LocalObject is CustomLocalStateData cdi &&
_viewHandler.VirtualView is View view)
{
HandleDrop(view, cdi.DataPackage);
HandleDropCompleted(cdi.View);
}
}
public bool CanHandleSession(UIDropInteraction interaction, IUIDropSession session)
{
if (session.LocalDragSession == null)
{
return(false);
}
if (session.LocalDragSession.Items.Length > 0 &&
session.LocalDragSession.Items[0].LocalObject is CustomLocalStateData)
{
return(true);
}
return(false);
}
public void PerformDrop(UIDropInteraction interaction, IUIDropSession session)
{
if (session.LocalDragSession == null)
{
DropPoint = session.LocationInView(interaction.View);
foreach (var dragItem in session.Items)
{
LoadImage(dragItem.ItemProvider, DropPoint);
}
}
else
{
MovePoint = session.LocationInView(interaction.View);
}
}
public void SessionDidExit(UIDropInteraction interaction, IUIDropSession session)
{
if (interaction.View is IVisualElementRenderer renderer)
{
DataPackage package = null;
if (session.LocalDragSession.Items.Length > 0 &&
session.LocalDragSession.Items[0].LocalObject is CustomLocalStateData cdi)
{
package = cdi.DataPackage;
}
if (HandleDragLeave((View)renderer.Element, package))
{
}
}
}
public void PerformDrop(UIDropInteraction interaction, IUIDropSession session)
{
var label = interaction == oddDropInteraction ? OddNumbersLabel : EvenNumbersLabel;
session.LoadObjects <NSString>(strings =>
{
if (String.IsNullOrEmpty(label.Text))
{
label.Text = strings[0];
}
else
{
label.Text = $"{strings[0]}, {label.Text}";
}
});
GenerateNumber();
}
public UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
UIDropProposal proposal;
var isEven = (session.Items[0].LocalObject as NSNumber).BoolValue;
if (interaction == oddDropInteraction && !isEven)
{
proposal = new UIDropProposal(UIDropOperation.Copy);
}
else if (interaction == evenDropInteraction && isEven)
{
proposal = new UIDropProposal(UIDropOperation.Copy);
}
else
{
proposal = new UIDropProposal(UIDropOperation.Forbidden);
}
return(proposal);
}
protected void SetupDragAndDrop()
{
NumberLabel.UserInteractionEnabled = true;
EvenNumbersLabel.UserInteractionEnabled = true;
OddNumbersLabel.UserInteractionEnabled = true;
var numberDragInteraction = new UIDragInteraction(this);
NumberLabel.AddInteraction(numberDragInteraction);
// On iPad, this defaults to true. On iPhone, this defaults to
// false. Since this app should work on the iPhone, enable the the
// drag interaction.
numberDragInteraction.Enabled = true;
evenDropInteraction = new UIDropInteraction(this);
EvenNumbersLabel.AddInteraction(evenDropInteraction);
oddDropInteraction = new UIDropInteraction(this);
OddNumbersLabel.AddInteraction(oddDropInteraction);
}
public UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
var dropLocation = session.LocationInView(View);
UpdateLayers(dropLocation);
var operation = new UIDropOperation();
if (ImageView.Frame.Contains(dropLocation))
{
operation = session.LocalDragSession == null ? UIDropOperation.Copy : UIDropOperation.Move;
}
else
{
// Cancel dropping if it's not inside the image view.
operation = UIDropOperation.Cancel;
}
return(new UIDropProposal(operation));
}
public void WillAnimateDrop(UIDropInteraction interaction, UIDragItem item, IUIDragAnimating animator)
{
animator.AddAnimations(() => {
FadeItems(new UIDragItem[] { item }, 0f);
});
var movePoint = MovePoint; //DropPoint
animator.AddCompletion((err) => {
var index = item.LocalObject as NSNumber;
if (index != null)
{
var i = index.Int32Value;
if (i >= 0)
{
Views[i].Center = movePoint;
Views[i].Alpha = 1f;
}
}
});
}
public override void ViewDidLoad()
{
base.ViewDidLoad();
ImageView.Layer.BorderColor = UIColor.Green.CGColor;
ImageView.Layer.BorderWidth = 0.0f;
View.Layer.BorderColor = UIColor.Red.CGColor;
// 'UserInteractionEnabled' is needed for drag and drop.
ImageView.UserInteractionEnabled = true;
// Allow dragging.
var dragInteraction = new UIDragInteraction(this);
ImageView.AddInteraction(dragInteraction);
// Allow dropping.
var dropInteraction = new UIDropInteraction(this);
View.AddInteraction(dropInteraction);
}
public UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
UIDropOperation operation = UIDropOperation.Cancel;
if (session.LocalDragSession == null)
{
return(new UIDropProposal(operation));
}
DataPackage package = null;
if (session.LocalDragSession.Items.Length > 0 &&
session.LocalDragSession.Items[0].LocalObject is CustomLocalStateData cdi)
{
package = cdi.DataPackage;
}
if (HandleDragOver((View)_viewHandler.VirtualView, package))
{
operation = UIDropOperation.Copy;
}
return(new UIDropProposal(operation));
}
void LoadRecognizers()
{
if (ElementGestureRecognizers == null)
{
return;
}
#if __MOBILE__
if (_shouldReceiveTouch == null)
{
// Cache this so we don't create a new UITouchEventArgs instance for every recognizer
_shouldReceiveTouch = ShouldReceiveTouch;
}
#endif
#if __MOBILE__
UIDragInteraction uIDragInteraction = null;
UIDropInteraction uIDropInteraction = null;
if (_dragAndDropDelegate != null)
{
foreach (var interaction in _renderer.NativeView.Interactions)
{
if (interaction is UIDragInteraction uIDrag && uIDrag.Delegate == _dragAndDropDelegate)
{
uIDragInteraction = uIDrag;
}
if (interaction is UIDropInteraction uiDrop && uiDrop.Delegate == _dragAndDropDelegate)
{
uIDropInteraction = uiDrop;
}
}
}
bool dragFound = false;
bool dropFound = false;
#endif
for (int i = 0; i < ElementGestureRecognizers.Count; i++)
{
IGestureRecognizer recognizer = ElementGestureRecognizers[i];
if (_gestureRecognizers.ContainsKey(recognizer))
{
continue;
}
var nativeRecognizer = GetNativeRecognizer(recognizer);
if (nativeRecognizer != null && _handler != null)
{
#if __MOBILE__
nativeRecognizer.ShouldReceiveTouch = _shouldReceiveTouch;
#endif
_handler.AddGestureRecognizer(nativeRecognizer);
_gestureRecognizers[recognizer] = nativeRecognizer;
}
#if __MOBILE__
if (Forms.IsiOS11OrNewer && recognizer is DragGestureRecognizer)
{
dragFound = true;
_dragAndDropDelegate = _dragAndDropDelegate ?? new DragAndDropDelegate();
if (uIDragInteraction == null)
{
var interaction = new UIDragInteraction(_dragAndDropDelegate);
interaction.Enabled = true;
_renderer.NativeView.AddInteraction(interaction);
}
}
if (Forms.IsiOS11OrNewer && recognizer is DropGestureRecognizer)
{
dropFound = true;
_dragAndDropDelegate = _dragAndDropDelegate ?? new DragAndDropDelegate();
if (uIDropInteraction == null)
{
var interaction = new UIDropInteraction(_dragAndDropDelegate);
_renderer.NativeView.AddInteraction(interaction);
}
}
#endif
}
#if __MOBILE__
if (!dragFound && uIDragInteraction != null)
{
_renderer.NativeView.RemoveInteraction(uIDragInteraction);
}
if (!dropFound && uIDropInteraction != null)
{
_renderer.NativeView.RemoveInteraction(uIDropInteraction);
}
#endif
var toRemove = _gestureRecognizers.Keys.Where(key => !ElementGestureRecognizers.Contains(key)).ToArray();
for (int i = 0; i < toRemove.Length; i++)
{
IGestureRecognizer gestureRecognizer = toRemove[i];
var uiRecognizer = _gestureRecognizers[gestureRecognizer];
_gestureRecognizers.Remove(gestureRecognizer);
_handler.RemoveGestureRecognizer(uiRecognizer);
uiRecognizer.Dispose();
}
}
public void SessionDidEnter(UIDropInteraction interaction, IUIDropSession session)
{
Alpha = 1.0f;
}
public override UIDropProposal SessionDidUpdate(UIDropInteraction interaction, IUIDropSession session)
{
Console.WriteLine($"SessionDidUpdate ({interaction}, {session})");
return(new UIDropProposal(UIDropOperation.Copy));
}
public void SessionDidEnd(UIDropInteraction interaction, IUIDropSession session)
{
Alpha = 0.5f;
}
public bool CanHandleSession(UIDropInteraction interaction, IUIDropSession session)
{
return(session.CanLoadObjects(typeof(UIImage)));
}
public override bool CanHandleSession(UIDropInteraction interaction, IUIDropSession session)
{
Console.WriteLine($"CanHandleSession ({interaction}, {session})");
return(session.CanLoadObjectsOfClass(new Class(typeof(NSString))));
}
void LoadRecognizers()
{
if (ElementGestureRecognizers == null)
{
return;
}
if (_shouldReceiveTouch == null)
{
// Cache this so we don't create a new UITouchEventArgs instance for every recognizer
_shouldReceiveTouch = ShouldReceiveTouch;
}
CalculateUserInteractionEnabled();
UIDragInteraction?uIDragInteraction = null;
UIDropInteraction?uIDropInteraction = null;
if (_dragAndDropDelegate != null && _platformView != null)
{
if (PlatformVersion.IsAtLeast(11))
{
foreach (var interaction in _platformView.Interactions)
{
if (interaction is UIDragInteraction uIDrag && uIDrag.Delegate == _dragAndDropDelegate)
{
uIDragInteraction = uIDrag;
}
if (interaction is UIDropInteraction uiDrop && uiDrop.Delegate == _dragAndDropDelegate)
{
uIDropInteraction = uiDrop;
}
}
}
}
bool dragFound = false;
bool dropFound = false;
if (_platformView != null &&
_handler.VirtualView is View v &&
v.TapGestureRecognizerNeedsDelegate() &&
(_platformView.AccessibilityTraits & UIAccessibilityTrait.Button) != UIAccessibilityTrait.Button)
{
_platformView.AccessibilityTraits |= UIAccessibilityTrait.Button;
_addedFlags |= UIAccessibilityTrait.Button;
if (PlatformVersion.IsAtLeast(13))
{
_defaultAccessibilityRespondsToUserInteraction = _platformView.AccessibilityRespondsToUserInteraction;
_platformView.AccessibilityRespondsToUserInteraction = true;
}
}
for (int i = 0; i < ElementGestureRecognizers.Count; i++)
{
IGestureRecognizer recognizer = ElementGestureRecognizers[i];
if (_gestureRecognizers.ContainsKey(recognizer))
{
continue;
}
var nativeRecognizer = GetPlatformRecognizer(recognizer);
if (nativeRecognizer != null && _platformView != null)
{
nativeRecognizer.ShouldReceiveTouch = _shouldReceiveTouch;
_platformView.AddGestureRecognizer(nativeRecognizer);
_gestureRecognizers[recognizer] = nativeRecognizer;
}
if (PlatformVersion.IsAtLeast(11) && recognizer is DragGestureRecognizer)
{
dragFound = true;
_dragAndDropDelegate = _dragAndDropDelegate ?? new DragAndDropDelegate(_handler);
if (uIDragInteraction == null && _handler.PlatformView != null)
{
var interaction = new UIDragInteraction(_dragAndDropDelegate);
interaction.Enabled = true;
_handler.PlatformView.AddInteraction(interaction);
}
}
if (PlatformVersion.IsAtLeast(11) && recognizer is DropGestureRecognizer)
{
dropFound = true;
_dragAndDropDelegate = _dragAndDropDelegate ?? new DragAndDropDelegate(_handler);
if (uIDropInteraction == null && _handler.PlatformView != null)
{
var interaction = new UIDropInteraction(_dragAndDropDelegate);
_handler.PlatformView.AddInteraction(interaction);
}
}
}
if (PlatformVersion.IsAtLeast(11))
{
if (!dragFound && uIDragInteraction != null && _handler.PlatformView != null)
{
_handler.PlatformView.RemoveInteraction(uIDragInteraction);
}
if (!dropFound && uIDropInteraction != null && _handler.PlatformView != null)
{
_handler.PlatformView.RemoveInteraction(uIDropInteraction);
}
}
var toRemove = new List <IGestureRecognizer>();
foreach (var key in _gestureRecognizers.Keys)
{
if (!ElementGestureRecognizers.Contains(key))
{
toRemove.Add(key);
}
}
for (int i = 0; i < toRemove.Count; i++)
{
IGestureRecognizer gestureRecognizer = toRemove[i];
var uiRecognizer = _gestureRecognizers[gestureRecognizer];
_gestureRecognizers.Remove(gestureRecognizer);
if (_platformView != null)
{
_platformView.RemoveGestureRecognizer(uiRecognizer);
}
uiRecognizer.Dispose();
}
}
private void SetupDrop()
{
UserInteractionEnabled = true;
DropInteraction = new UIDropInteraction(this);
AddInteraction(DropInteraction);
}
