internal static IObservable<CustomDragDropKeyStates> GetKeyStateChangedOnSelfAndSiblingsAlways(this UIElement that, CustomDragDropKeyStates initialState)
{
IEnumerable<UIElement> enumerable = from popup in that.GetVisualDescendants().OfType<Popup>()
select popup.Child into popupRoot
where popupRoot != null
select popupRoot;
return GetKeyStateChanged(Enumerable.Aggregate<IObservable<Event<MouseButtonEventArgs>>, IObservable<Event<MouseButtonEventArgs>>>(from popupRoot in enumerable select popupRoot.GetMouseLeftButtonDownAlways(), that.GetMouseLeftButtonDownAlways(), (Func<IObservable<Event<MouseButtonEventArgs>>, IObservable<Event<MouseButtonEventArgs>>, IObservable<Event<MouseButtonEventArgs>>>) ((left, right) => left.Merge<Event<MouseButtonEventArgs>>(right))), Enumerable.Aggregate<IObservable<Event<MouseButtonEventArgs>>, IObservable<Event<MouseButtonEventArgs>>>(from popupRoot in enumerable select popupRoot.GetMouseLeftButtonUpAlways(), that.GetMouseLeftButtonUpAlways(), (Func<IObservable<Event<MouseButtonEventArgs>>, IObservable<Event<MouseButtonEventArgs>>, IObservable<Event<MouseButtonEventArgs>>>) ((left, right) => left.Merge<Event<MouseButtonEventArgs>>(right))), Enumerable.Aggregate<IObservable<Event<KeyEventArgs>>, IObservable<Event<KeyEventArgs>>>(from popupRoot in enumerable select popupRoot.GetKeyUpAlways(), that.GetKeyUpAlways(), (Func<IObservable<Event<KeyEventArgs>>, IObservable<Event<KeyEventArgs>>, IObservable<Event<KeyEventArgs>>>) ((left, right) => left.Merge<Event<KeyEventArgs>>(right))), Enumerable.Aggregate<IObservable<Event<KeyEventArgs>>, IObservable<Event<KeyEventArgs>>>(from popupRoot in enumerable select popupRoot.GetKeyDownAlways(), that.GetKeyDownAlways(), (Func<IObservable<Event<KeyEventArgs>>, IObservable<Event<KeyEventArgs>>, IObservable<Event<KeyEventArgs>>>) ((left, right) => left.Merge<Event<KeyEventArgs>>(right))), initialState);
}
public static void DoDragDrop(DependencyObject dragSource, object data, CustomDragDropEffects allowedEffects, CustomDragDropKeyStates initialKeyState)
{
_dragOperationInProgress = new CustomDragOperation(dragSource, data, allowedEffects, initialKeyState);
_dragOperationInProgress.Subscribe<CustomDragDropEffects>(delegate (CustomDragDropEffects effects) {
CustomDragDropCompletedEventArgs args = new CustomDragDropCompletedEventArgs {
Effects = effects
};
OnDragCompleted(args);
});
}
internal static IObservable<CustomDragDropKeyStates> GetKeyStateChangedAlways(this UIElement that, CustomDragDropKeyStates initialState)
{
return GetKeyStateChanged(that.GetMouseLeftButtonDownAlways(), that.GetMouseLeftButtonUpAlways(), that.GetKeyDownAlways(), that.GetKeyUpAlways(), initialState);
}
private static IObservable<CustomDragDropKeyStates> GetKeyStateChanged(IObservable<Event<MouseButtonEventArgs>> mouseDownObservable, IObservable<Event<MouseButtonEventArgs>> mouseUpObservable, IObservable<Event<KeyEventArgs>> keyDownObservable, IObservable<Event<KeyEventArgs>> keyUpObservable, CustomDragDropKeyStates initialState)
{
return mouseDownObservable.Select<Event<MouseButtonEventArgs>, Tuple<bool, CustomDragDropKeyStates>>(ev => Tuple.Create<bool, CustomDragDropKeyStates>(true, CustomDragDropKeyStates.LeftMouseButton)).Merge<Tuple<bool, CustomDragDropKeyStates>>(mouseUpObservable.Select<Event<MouseButtonEventArgs>, Tuple<bool, CustomDragDropKeyStates>>(ev => Tuple.Create<bool, CustomDragDropKeyStates>(false, CustomDragDropKeyStates.LeftMouseButton))).Merge<Tuple<bool, CustomDragDropKeyStates>>(keyUpObservable.Select<Event<KeyEventArgs>, Tuple<bool, CustomDragDropKeyStates>>(ev => Tuple.Create<bool, CustomDragDropKeyStates>(false, ToDragDropKeyStates(ev.EventArgs.Key)))).Merge<Tuple<bool, CustomDragDropKeyStates>>(keyDownObservable.Select<Event<KeyEventArgs>, Tuple<bool, CustomDragDropKeyStates>>(ev => Tuple.Create<bool, CustomDragDropKeyStates>(true, ToDragDropKeyStates(ev.EventArgs.Key)))).Scan<Tuple<bool, CustomDragDropKeyStates>, CustomDragDropKeyStates>(initialState, delegate (CustomDragDropKeyStates acc, Tuple<bool, CustomDragDropKeyStates> current) {
if (current.Item1)
{
return (acc | ((CustomDragDropKeyStates) current.Item2));
}
return (acc & ((CustomDragDropKeyStates) ~current.Item2));
});
}