public static IDisposable MakeDraggable(this Graphic graphic, Map map)
{
graphic.RequireArgument<Graphic>("graphic").NotNull<Graphic>();
map.RequireArgument<Map>("map").NotNull<Map>();
//IObservable<IEvent<MouseEventArgs>> graphicMouseMove = Observable.FromEvent
// (
// ( EventHandler<MouseEventArgs> ev ) => new MouseEventHandler( ev ),
// ev => graphic.MouseMove += ev,
// ev => graphic.MouseMove += ev
// );
IObservable<IEvent<MouseEventArgs>> mapMouseMove = Observable.FromEvent
(
(EventHandler<MouseEventArgs> ev) => new MouseEventHandler(ev),
ev => map.MouseMove += ev,
ev => map.MouseMove += ev
);
IObservable<IEvent<MouseButtonEventArgs>> graphicLeftMouseButtonDown = Observable.FromEvent
(
(EventHandler<MouseButtonEventArgs> ev) => new MouseButtonEventHandler(ev),
ev => graphic.MouseLeftButtonDown += ev,
ev => graphic.MouseLeftButtonDown -= ev
);
//IObservable<IEvent<MouseButtonEventArgs>> graphicLeftMouseButtonUp = Observable.FromEvent
// (
// (EventHandler<MouseButtonEventArgs> ev) => new MouseButtonEventHandler(ev),
// ev => graphic.MouseLeftButtonUp += ev,
// ev => graphic.MouseLeftButtonUp -= ev
// );
IObservable<IEvent<MouseButtonEventArgs>> mapLeftMouseButtonUp = Observable.FromEvent
(
(EventHandler<MouseButtonEventArgs> ev) => new MouseButtonEventHandler(ev),
ev => map.MouseLeftButtonUp += ev,
ev => map.MouseLeftButtonUp -= ev
);
//var stopper = graphicLeftMouseButtonUp.Merge(mapLeftMouseButtonUp);
//var dragger = graphicMouseMove.Merge(mapMouseMove);
var stopper = mapLeftMouseButtonUp;
var dragger = mapMouseMove;
IObservable<IEvent<MouseEventArgs>> drag = dragger.SkipUntil(graphicLeftMouseButtonDown)
.TakeUntil(stopper)
.Repeat();
Func<IEvent<MouseEventArgs>, IEvent<MouseEventArgs>, Unit> handler = (prev, cur) =>
{
var prevMapPoint = map.ScreenToMap(prev.EventArgs.GetPosition(map));
var curMapPoint = map.ScreenToMap(cur.EventArgs.GetPosition(map));
var deltaX = curMapPoint.X - prevMapPoint.X;
var deltaY = curMapPoint.Y - prevMapPoint.Y;
graphic.Geometry.Offset(deltaX, deltaY);
return new Unit();
};
Disposables removeHandlers = new Disposables();
removeHandlers.Subscriptions.Add(graphicLeftMouseButtonDown.Subscribe(e => e.EventArgs.Handled = true));
removeHandlers.Subscriptions.Add
(
drag
.Zip(drag.Skip(1), handler)
.Subscribe()
);
return removeHandlers;
}
public static IDisposable MakeDraggable(this GraphicsLayer gLayer, Map map)
{
gLayer.RequireArgument<GraphicsLayer>("gLayer").NotNull<GraphicsLayer>();
map.RequireArgument<Map>("map").NotNull<Map>();
IObservable<IEvent<MouseEventArgs>> dragger = Observable.FromEvent
(
(EventHandler<MouseEventArgs> ev) => new MouseEventHandler(ev),
ev => map.MouseMove += ev,
ev => map.MouseMove += ev
);
IObservable<IEvent<GraphicMouseButtonEventArgs>> starter = Observable.FromEvent
(
(EventHandler<GraphicMouseButtonEventArgs> ev) => new GraphicsLayer.MouseButtonEventHandler(ev),
ev => gLayer.MouseLeftButtonDown += ev,
ev => gLayer.MouseLeftButtonDown -= ev
);
IObservable<IEvent<MouseButtonEventArgs>> stopper = Observable.FromEvent
(
(EventHandler<MouseButtonEventArgs> ev) => new MouseButtonEventHandler(ev),
ev => map.MouseLeftButtonUp += ev,
ev => map.MouseLeftButtonUp -= ev
);
IObservable<IEvent<MouseEventArgs>> drag = dragger.SkipUntil(starter)
.TakeUntil(stopper)
.Repeat();
Guid state = Guid.NewGuid();
Guid lastState = state;
Graphic g = null;
Func<IEvent<MouseEventArgs>, IEvent<MouseEventArgs>, Unit> handler = (prev, cur) =>
{
if (g == null)
return new Unit();
if (state != lastState)
{
lastState = state;
return new Unit();
}
var prevMapPoint = map.ScreenToMap(prev.EventArgs.GetPosition(map));
var curMapPoint = map.ScreenToMap(cur.EventArgs.GetPosition(map));
g.Geometry.Offset((curMapPoint.X - prevMapPoint.X), (curMapPoint.Y - prevMapPoint.Y));
lastState = state;
return new Unit();
};
Disposables removeHandlers = new Disposables();
removeHandlers.Subscriptions.Add(starter.Subscribe(e =>
{
g = e.EventArgs.Graphic;
state = Guid.NewGuid();
e.EventArgs.Handled = true;
}
));
removeHandlers.Subscriptions.Add(stopper.Subscribe(e =>
{
state = Guid.NewGuid();
g = null;
}));
removeHandlers.Subscriptions.Add
(
drag
.Zip(drag.Skip(1), handler)
.Subscribe()
);
return removeHandlers;
}
