private TouchTrackingPoint GetScreenPointerCoordinates(
int[] screenLocation, MotionEvent motionEvent, int pointerIndex)
{
var screenPointerCoords =
new TouchTrackingPoint(
screenLocation[0] + motionEvent.GetX(pointerIndex),
screenLocation[1] + motionEvent.GetY(pointerIndex));
return(screenPointerCoords);
}
private void FireEvent(TouchHandler touchEffect, int id, TouchActionType actionType, TouchTrackingPoint pointerLocation, bool isInContact)
{
// Get the location of the pointer within the view
touchEffect._view.GetLocationOnScreen(_twoIntArray);
double x = pointerLocation.X - _twoIntArray[0];
double y = pointerLocation.Y - _twoIntArray[1];
TouchTrackingPoint point = new TouchTrackingPoint((float)_fromPixels(x), (float)_fromPixels(y));
// Call the method
OnTouchAction(touchEffect._view,
new TouchActionEventArgs(id, actionType, point, isInContact));
}
private void FireEvent(TouchRecognizer recognizer, long id, TouchActionType actionType, UITouch touch, bool isInContact)
{
// Convert touch location to Xamarin.Forms Point value
CGPoint cgPoint = touch.LocationInView(recognizer.View);
TouchTrackingPoint xfPoint = new TouchTrackingPoint((float)cgPoint.X, (float)cgPoint.Y);
// Get the method to call for firing events
Action <UIView, TouchActionEventArgs> onTouchAction = recognizer._touchHandler.OnTouchAction;
// Call that method
onTouchAction(recognizer._view,
new TouchActionEventArgs(id, actionType, xfPoint, isInContact));
}
private void CheckForBoundaryHop(int id, TouchTrackingPoint pointerLocation)
{
TouchHandler touchEffectHit = null;
foreach (View view in _viewDictionary.Keys)
{
// Get the view rectangle
try
{
view.GetLocationOnScreen(_twoIntArray);
}
catch // System.ObjectDisposedException: Cannot access a disposed object.
{
continue;
}
TouchTrackingRect viewRect = new TouchTrackingRect(_twoIntArray[0], _twoIntArray[1], view.Width, view.Height);
if (viewRect.Contains(pointerLocation))
{
touchEffectHit = _viewDictionary[view];
}
}
if (touchEffectHit != _idToTouchHandlerDictionary[id])
{
if (_idToTouchHandlerDictionary[id] != null)
{
FireEvent(_idToTouchHandlerDictionary[id], id, TouchActionType.Exited, pointerLocation, true);
}
if (touchEffectHit != null)
{
FireEvent(touchEffectHit, id, TouchActionType.Entered, pointerLocation, true);
}
_idToTouchHandlerDictionary[id] = touchEffectHit;
}
}
SKPoint ConvertToPixel(TouchTrackingPoint pt)
{
return(new SKPoint((float)(canvasView.CanvasSize.Width * pt.X / canvasView.Width),
(float)(canvasView.CanvasSize.Height * pt.Y / canvasView.Height)));
}
private void OnTouch(object sender, View.TouchEventArgs args)
{
// Two object common to all the events
View senderView = sender as View;
MotionEvent motionEvent = args.Event;
// Get the pointer index
int pointerIndex = motionEvent.ActionIndex;
// Get the id that identifies a finger over the course of its progress
int id = motionEvent.GetPointerId(pointerIndex);
senderView.GetLocationOnScreen(_twoIntArray);
TouchTrackingPoint screenPointerCoords = new TouchTrackingPoint(_twoIntArray[0] + motionEvent.GetX(pointerIndex),
_twoIntArray[1] + motionEvent.GetY(pointerIndex));
// Use ActionMasked here rather than Action to reduce the number of possibilities
switch (args.Event.ActionMasked)
{
case MotionEventActions.Down:
case MotionEventActions.PointerDown:
FireEvent(this, id, TouchActionType.Pressed, screenPointerCoords, true);
_idToTouchHandlerDictionary.Add(id, this);
_capture = Capture;
break;
case MotionEventActions.Move:
// Multiple Move events are bundled, so handle them in a loop
for (pointerIndex = 0; pointerIndex < motionEvent.PointerCount; pointerIndex++)
{
id = motionEvent.GetPointerId(pointerIndex);
if (_capture)
{
senderView.GetLocationOnScreen(_twoIntArray);
screenPointerCoords = new TouchTrackingPoint(_twoIntArray[0] + motionEvent.GetX(pointerIndex),
_twoIntArray[1] + motionEvent.GetY(pointerIndex));
FireEvent(this, id, TouchActionType.Moved, screenPointerCoords, true);
}
else
{
CheckForBoundaryHop(id, screenPointerCoords);
if (_idToTouchHandlerDictionary[id] != null)
{
FireEvent(_idToTouchHandlerDictionary[id], id, TouchActionType.Moved, screenPointerCoords, true);
}
}
}
break;
case MotionEventActions.Up:
case MotionEventActions.Pointer1Up:
if (_capture)
{
FireEvent(this, id, TouchActionType.Released, screenPointerCoords, false);
}
else
{
CheckForBoundaryHop(id, screenPointerCoords);
if (_idToTouchHandlerDictionary[id] != null)
{
FireEvent(_idToTouchHandlerDictionary[id], id, TouchActionType.Released, screenPointerCoords, false);
}
}
_idToTouchHandlerDictionary.Remove(id);
break;
case MotionEventActions.Cancel:
if (_capture)
{
FireEvent(this, id, TouchActionType.Cancelled, screenPointerCoords, false);
}
else
{
if (_idToTouchHandlerDictionary[id] != null)
{
FireEvent(_idToTouchHandlerDictionary[id], id, TouchActionType.Cancelled, screenPointerCoords, false);
}
}
_idToTouchHandlerDictionary.Remove(id);
break;
}
}
public bool Contains(TouchTrackingPoint point)
{
return(Contains(point.X, point.Y));
}
private void OnTouch(object sender, View.TouchEventArgs args)
{
// Two object common to all the events
View senderView = sender as View;
MotionEvent motionEvent = args.Event;
// Get the pointer index
int pointerIndex = motionEvent.ActionIndex;
// Get the id that identifies a finger over the course of its progress
int id = motionEvent.GetPointerId(pointerIndex);
senderView.GetLocationOnScreen(_locationOnScreen);
TouchTrackingPoint screenPointerCoords =
GetScreenPointerCoordinates(_locationOnScreen, motionEvent, pointerIndex);
// Use ActionMasked here rather than Action to reduce the number of possibilities
switch (args.Event.ActionMasked)
{
case MotionEventActions.Down:
case MotionEventActions.PointerDown:
FireEvent(this, id, TouchActionType.Pressed, screenPointerCoords, true);
_idToTouchHandlerDictionary.Add(id, this);
_capture = Capture;
if (UseTouchSlop)
{
_lastX = args.Event.GetX();
_lastY = args.Event.GetY();
}
break;
case MotionEventActions.Move:
if (motionEvent.PointerCount == 1 && UseTouchSlop)
{
id = motionEvent.GetPointerId(0);
senderView.GetLocationOnScreen(_locationOnScreen);
if (!_moveInProgress)
{
var x = args.Event.GetX();
var y = args.Event.GetY();
var xDiff = Math.Abs(_lastX - x);
var yDiff = Math.Abs(_lastY - y);
if (xDiff > _slop || yDiff > _slop)
{
_moveInProgress = true;
}
}
if (_moveInProgress)
{
screenPointerCoords = GetScreenPointerCoordinates(_locationOnScreen, motionEvent, pointerIndex);
FireEvent(this, id, TouchActionType.Moved, screenPointerCoords, true);
}
break;
}
_moveInProgress = false;
_lastX = 0;
_lastY = 0;
// Multiple Move events are bundled, so handle them in a loop
for (pointerIndex = 0; pointerIndex < motionEvent.PointerCount; pointerIndex++)
{
id = motionEvent.GetPointerId(pointerIndex);
if (_capture)
{
senderView.GetLocationOnScreen(_locationOnScreen);
screenPointerCoords = GetScreenPointerCoordinates(_locationOnScreen, motionEvent, pointerIndex);
FireEvent(this, id, TouchActionType.Moved, screenPointerCoords, true);
}
else
{
CheckForBoundaryHop(id, screenPointerCoords);
if (_idToTouchHandlerDictionary[id] != null)
{
FireEvent(_idToTouchHandlerDictionary[id], id, TouchActionType.Moved, screenPointerCoords, true);
}
}
}
break;
case MotionEventActions.Up:
case MotionEventActions.Pointer1Up:
if (_capture)
{
FireEvent(this, id, TouchActionType.Released, screenPointerCoords, false);
}
else
{
CheckForBoundaryHop(id, screenPointerCoords);
if (_idToTouchHandlerDictionary[id] != null)
{
FireEvent(_idToTouchHandlerDictionary[id], id, TouchActionType.Released, screenPointerCoords, false);
}
}
_idToTouchHandlerDictionary.Remove(id);
_moveInProgress = false;
_lastX = 0;
_lastY = 0;
break;
case MotionEventActions.Cancel:
if (_capture)
{
FireEvent(this, id, TouchActionType.Cancelled, screenPointerCoords, false);
}
else
{
if (_idToTouchHandlerDictionary[id] != null)
{
FireEvent(_idToTouchHandlerDictionary[id], id, TouchActionType.Cancelled, screenPointerCoords, false);
}
}
_idToTouchHandlerDictionary.Remove(id);
_moveInProgress = false;
_lastX = 0;
_lastY = 0;
break;
}
}
