Use TapGestureTracker on all platforms and let is detect double tap too

Mapsui.UI.Android/MapControl.cs

@@ -17,32 +17,13 @@ public enum SkiaRenderMode
     Software
 }
 
-internal class MapControlGestureListener : GestureDetector.SimpleOnGestureListener
-{
-    public EventHandler<GestureDetector.FlingEventArgs>? Fling;
-#if NET7_0
-    public override bool OnFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)
-#else
-    public override bool OnFling(MotionEvent? e1, MotionEvent e2, float velocityX, float velocityY)
-#endif
-    {
-        if (Fling != null)
-        {
-            Fling?.Invoke(this, new GestureDetector.FlingEventArgs(false, e1, e2, velocityX, velocityY));
-            return true;
-        }
-
-        return base.OnFling(e1, e2, velocityX, velocityY);
-    }
-}
-
 public partial class MapControl : ViewGroup, IMapControl
 {
     private View? _canvas;
-    private GestureDetector? _gestureDetector;
     private Handler? _mainLooperHandler;
     private SkiaRenderMode _renderMode = SkiaRenderMode.Hardware;
     private readonly ManipulationTracker _manipulationTracker = new();
+    private readonly TapGestureTracker _tapGestureTracker = new();
 
     public MapControl(Context context, IAttributeSet attrs) :
         base(context, attrs)
@@ -72,12 +53,6 @@ private void LocalConstructor()
 
         // Pointer events
         Touch += MapControl_Touch;
-        var listener = new MapControlGestureListener(); // Todo: Find out if/why we need this custom gesture detector. Why not the _gestureDetector?
-        listener.Fling += OnFling;
-        _gestureDetector?.Dispose();
-        _gestureDetector = new GestureDetector(Context, listener);
-        _gestureDetector.SingleTapConfirmed += OnSingleTapped;
-        _gestureDetector.DoubleTap += OnDoubleTapped;
     }
 
     private void CanvasOnPaintSurface(object? sender, SKPaintSurfaceEventArgs args)
@@ -117,27 +92,6 @@ public SkiaRenderMode RenderMode
         }
     }
 
-    private void OnSingleTapped(object? sender, GestureDetector.SingleTapConfirmedEventArgs e)
-    {
-        if (e.Event == null)
-            return;
-
-        var position = GetScreenPosition(e.Event, this);
-        if (OnWidgetTapped(position, 1, false))
-            return;
-        OnInfo(CreateMapInfoEventArgs(position, position, 1));
-    }
-
-    private void OnDoubleTapped(object? sender, GestureDetector.DoubleTapEventArgs e)
-    {
-        if (e.Event == null)
-            return;
-
-        var position = GetScreenPosition(e.Event, this);
-        if (OnWidgetTapped(position, 2, false))
-            return;
-        OnInfo(CreateMapInfoEventArgs(position, position, 2));
-    }
 
     protected override void OnSizeChanged(int width, int height, int oldWidth, int oldHeight)
     {
@@ -175,25 +129,34 @@ public void MapControl_Touch(object? sender, TouchEventArgs args)
         if (args.Event is null)
             return;
 
-        if (_gestureDetector?.OnTouchEvent(args.Event) == true)
-            return;
-
         var locations = GetTouchLocations(args.Event, this, PixelDensity);
 
         switch (args.Event.Action)
         {
             case MotionEventActions.Down:
                 _manipulationTracker.Restart(locations);
-                if (OnWidgetPointerPressed(locations[0], false))
-                    return;
+                if (locations.Length == 1)
+                {
+                    _tapGestureTracker.Restart(locations[0]);
+                    if (OnWidgetPointerPressed(locations[0], false))
+                        return;
+                }
                 break;
             case MotionEventActions.Move:
-                if (OnWidgetPointerMoved(locations[0], true, false))
-                    return;
+                if (locations.Length == 1)
+                    if (OnWidgetPointerMoved(locations[0], true, false))
+                        return;
                 _manipulationTracker.Manipulate(locations, Map.Navigator.Manipulate);
                 break;
             case MotionEventActions.Up:
-                // Todo: Add HandleWidgetPointerUp
+                if (locations.Length == 1)
+                    _tapGestureTracker.IfTap(locations[0], MaxTapGestureMovement * PixelDensity, (p, c) =>
+                    {
+                        if (OnWidgetTapped(p, c, false))
+                            return;
+                        OnInfo(CreateMapInfoEventArgs(p, p, c));
+
+                    });
                 _manipulationTracker.Manipulate(locations, Map.Navigator.Manipulate);
                 Refresh();
                 break;
@@ -291,7 +254,6 @@ protected override void Dispose(bool disposing)
             _map?.Dispose();
             _mainLooperHandler?.Dispose();
             _canvas?.Dispose();
-            _gestureDetector?.Dispose();
         }
         CommonDispose(disposing);
 

Mapsui.UI.Avalonia/MapControl.cs

@@ -24,6 +24,7 @@ public partial class MapControl : UserControl, IMapControl, IDisposable
     private readonly ConcurrentDictionary<long, MPoint> _pointerLocations = new();
     private bool _shiftPressed;
     private readonly ManipulationTracker _manipulationTracker = new();
+    private readonly TapGestureTracker _tapGestureTracker = new();
 
     public MapControl()
     {
@@ -41,9 +42,6 @@ public MapControl()
         PointerCaptureLost += MapControl_PointerCaptureLost;
         PointerWheelChanged += MapControl_PointerWheelChanged;
 
-        Tapped += MapControl_Tapped;
-        DoubleTapped += MapControl_DoubleTapped;
-
         // Needed to track the state of _shiftPressed because DoubleTapped does not have KeyModifiers.
         KeyDown += (s, e) => _shiftPressed = GetShiftPressed(e.KeyModifiers);
         KeyUp += (s, e) => _shiftPressed = GetShiftPressed(e.KeyModifiers);
@@ -84,56 +82,62 @@ protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs chang
 
     private void MapControl_PointerPressed(object? sender, PointerPressedEventArgs e)
     {
-        if (!IsMouseDown(e))
+        if (IsHovering(e))
             return;
 
         var tapPosition = e.GetPosition(this).ToMapsui();
         _pointerLocations[e.Pointer.Id] = tapPosition;
 
-        _manipulationTracker.Restart(_pointerLocations.Values.ToArray());
-
-        if (OnWidgetPointerPressed(tapPosition, _shiftPressed))
-            return;
-
+        if (_pointerLocations.Count() == 1)
+        {
+            _tapGestureTracker.Restart(tapPosition);
+            _manipulationTracker.Restart(_pointerLocations.Values.ToArray());
+            if (OnWidgetPointerPressed(tapPosition, _shiftPressed))
+                return;
+        }
         e.Pointer.Capture(this);
     }
 
-    private bool IsMouseDown(PointerPressedEventArgs e) => e.GetCurrentPoint(this).Properties.IsLeftButtonPressed;
-
     private void MapControl_PointerMoved(object? sender, PointerEventArgs e)
     {
         var isHovering = IsHovering(e);
 
-        if (OnWidgetPointerMoved(e.GetPosition(this).ToMapsui(), !isHovering, _shiftPressed))
+        var position = e.GetPosition(this).ToMapsui();
+        if (OnWidgetPointerMoved(position, !isHovering, _shiftPressed))
             return;
 
         if (isHovering)
             return; // In case of hovering we just call the widget move event and ignore the event otherwise.
 
-        var pointerLocation = e.GetPosition(this).ToMapsui();
-        _pointerLocations[e.Pointer.Id] = pointerLocation;
+        _pointerLocations[e.Pointer.Id] = position;
 
         _manipulationTracker.Manipulate(_pointerLocations.Values.ToArray(), Map.Navigator.Manipulate);
 
         RefreshGraphics();
     }
 
-    private bool IsHovering(PointerEventArgs e)
-    {
-        return e.Pointer.Type == PointerType.Mouse && !e.GetCurrentPoint(this).Properties.IsLeftButtonPressed;
-    }
-
     private void MapControl_PointerReleased(object? sender, PointerReleasedEventArgs e)
     {
         _pointerLocations.TryRemove(e.Pointer.Id, out _);
         e.Pointer.Capture(null);
 
-        var pointerPosition = e.GetPosition(this).ToMapsui();
+        var position = e.GetPosition(this).ToMapsui();
+        _tapGestureTracker.IfTap(position, MaxTapGestureMovement * PixelDensity, (p, c) =>
+        {
+            if (OnWidgetTapped(p, c, _shiftPressed))
+                return;
+            OnInfo(CreateMapInfoEventArgs(p, p, c));
+        });
         _manipulationTracker.Manipulate(_pointerLocations.Values.ToArray(), Map.Navigator.Manipulate);
 
         Refresh();
     }
 
+    private bool IsHovering(PointerEventArgs e)
+    {
+        return e.Pointer.Type == PointerType.Mouse && !e.GetCurrentPoint(this).Properties.IsLeftButtonPressed;
+    }
+
     private void MapControl_PointerWheelChanged(object? sender, PointerWheelEventArgs e)
     {
         // In Avalonia the touchpad can trigger the mouse wheel event. In that case there are more events and the Delta.Y is a double value, 
@@ -157,22 +161,6 @@ private void MapControl_PointerCaptureLost(object? sender, PointerCaptureLostEve
         ClearTouchState();
     }
 
-    private void MapControl_Tapped(object? sender, TappedEventArgs e)
-    {
-        var position = e.GetPosition(this).ToMapsui();
-        if (OnWidgetTapped(position, 1, _shiftPressed))
-            return;
-        OnInfo(CreateMapInfoEventArgs(position, position, 2));
-    }
-
-    private void MapControl_DoubleTapped(object? sender, TappedEventArgs e)
-    {
-        var position = e.GetPosition(this).ToMapsui();
-        if (OnWidgetTapped(position, 2, _shiftPressed))
-            return;
-        OnInfo(CreateMapInfoEventArgs(position, position, 2));
-    }
-
     public override void Render(DrawingContext context)
     {
         _drawOperation ??= new MapsuiCustomDrawOperation(new Rect(0, 0, Bounds.Width, Bounds.Height), this);

Mapsui.UI.Blazor/MapControl.cs

@@ -32,10 +32,6 @@ public partial class MapControl : ComponentBase, IMapControl
     public int ZoomButton { get; set; } = MouseButtons.Primary;
     public int ZoomModifier { get; set; } = Keys.Control;
     public string ElementId => _elementId;
-    /// <summary>
-    /// The movement allowed between a touch down and touch up in a touch gestures in device independent pixels.
-    /// </summary>
-    public int MaxTapGestureMovement { get; set; } = 8;
     private MapsuiJsInterop? Interop =>
             _interop == null && JsRuntime != null
                 ? _interop ??= new MapsuiJsInterop(JsRuntime)
@@ -162,17 +158,6 @@ private protected static void RunOnUIThread(Action action)
         action();
     }
 
-    protected void OnDblClick(MouseEventArgs e)
-    {
-        Catch.Exceptions(() =>
-        {
-            var location = e.ToLocation(_clientRect);
-            if (OnWidgetTapped(location, 2, GetShiftPressed()))
-                return;
-            OnInfo(CreateMapInfoEventArgs(location, location, 1));
-        });
-    }
-
     protected void OnMouseDown(MouseEventArgs e)
     {
         Catch.Exceptions(() =>
@@ -181,7 +166,7 @@ protected void OnMouseDown(MouseEventArgs e)
             _ = UpdateBoundingRectAsync();
 
             var location = e.ToLocation(_clientRect);
-            _tapGestureTracker.SetDownPosition(location);
+            _tapGestureTracker.Restart(location);
             _manipulationTracker.Restart([]);
 
             if (OnWidgetPointerPressed(location, GetShiftPressed()))
@@ -195,7 +180,6 @@ protected void OnMouseMove(MouseEventArgs e)
         {
             var isHovering = !IsMouseButtonPressed(e);
             var position = e.ToLocation(_clientRect);
-            _tapGestureTracker.SetLastMovePosition(position);
 
             if (OnWidgetPointerMoved(position, !isHovering, GetShiftPressed()))
                 return;
@@ -213,18 +197,18 @@ protected void OnMouseUp(MouseEventArgs e)
     {
         Catch.Exceptions(() =>
         {
-            var location = e.ToLocation(_clientRect);
+            var position = e.ToLocation(_clientRect);
 
-            _tapGestureTracker.IfTap((p) =>
+            _tapGestureTracker.IfTap(position, MaxTapGestureMovement * PixelDensity, (p, c) =>
             {
-                if (OnWidgetTapped(p, 1, GetShiftPressed()))
+                if (OnWidgetTapped(p, c, GetShiftPressed()))
                     return;
-                OnInfo(CreateMapInfoEventArgs(p, p, 1));
+                OnInfo(CreateMapInfoEventArgs(p, p, c));
 
-            }, MaxTapGestureMovement * PixelDensity);
+            });
 
-            _manipulationTracker.Manipulate([e.ToLocation(_clientRect)], Map.Navigator.Manipulate);
-            RefreshData();
+            _manipulationTracker.Manipulate([position], Map.Navigator.Manipulate);
+            Refresh();
         });
     }
 
@@ -276,7 +260,7 @@ public void OnTouchStart(TouchEventArgs e)
             var locations = e.TargetTouches.ToTouchLocations(_clientRect);
             if (OnWidgetPointerPressed(locations[0], GetShiftPressed()))
                 return;
-            _tapGestureTracker.SetDownPosition(locations[0]);
+            _tapGestureTracker.Restart(locations[0]);
             _manipulationTracker.Restart(locations);
         });
     }
@@ -286,9 +270,13 @@ public void OnTouchMove(TouchEventArgs e)
         Catch.Exceptions(() =>
         {
             var locations = e.TargetTouches.ToTouchLocations(_clientRect);
-            _tapGestureTracker.SetLastMovePosition(locations[0]);
-            if (OnWidgetPointerMoved(locations[0], true, GetShiftPressed()))
-                return;
+            if (locations.Length == 1)
+            {
+                var position = locations[0];
+                _tapGestureTracker.LastMovePosition = position;
+                if (OnWidgetPointerMoved(position, true, GetShiftPressed()))
+                    return;
+            }
             _manipulationTracker.Manipulate(locations.ToArray(), Map.Navigator.Manipulate);
         });
     }
@@ -297,12 +285,15 @@ public void OnTouchEnd(TouchEventArgs _)
     {
         Catch.Exceptions(() =>
         {
-            _tapGestureTracker.IfTap((position) =>
+            if (_tapGestureTracker.LastMovePosition == null)
+                return;
+
+            _tapGestureTracker.IfTap(_tapGestureTracker.LastMovePosition, MaxTapGestureMovement * PixelDensity, (p, c) =>
             {
-                if (OnWidgetTapped(position, 1, GetShiftPressed()))
+                if (OnWidgetTapped(p, c, GetShiftPressed()))
                     return;
-                OnInfo(CreateMapInfoEventArgs(position, position, 1));
-            }, MaxTapGestureMovement * PixelDensity);
+                OnInfo(CreateMapInfoEventArgs(p, p, c));
+            });
 
             RefreshData();
         });

Mapsui.UI.Blazor/MapControlComponent.razor

@@ -4,7 +4,7 @@
 
 <div @onmouseup=@OnMouseUp @onmousedown=@OnMouseDown 
      @onmousewheel=@OnMouseWheel @onmousemove=@OnMouseMove 
-     @onkeydown=@OnKeyDown @onkeyup=@OnKeyUp @ondblclick="OnDblClick"
+     @onkeydown=@OnKeyDown @onkeyup=@OnKeyUp
      @ontouchstart=@OnTouchStart @ontouchmove=@OnTouchMove @ontouchend=@OnTouchEnd
      @onwheel="OnMouseWheel" 
      name="@_elementId" id="@_elementId">