/// <summary>
/// Excutes the asyncronous action assoicated with the gesture
/// </summary>
/// <param name="result">The final <see cref="GestureResult"/></param>
/// <param name="param">The Gesture Paramater</param>
public async void ExecuteGesture(GestureResult result, object param)
{
if (_asyncExecute != null)
{
await Execute(result, param);
}
}
/// <summary>
/// Excutes the action assoicated with the gesture
/// </summary>
/// <param name="result">The final <see cref="GestureResult"/></param>
/// <param name="param">The Gesture Paramater cast to T before calling the action</param>
public void ExecuteGesture(GestureResult result, object param)
{
if (_execute != null)
{
_execute(result, param as T);
}
}
private void OnGesture(GestureResult gr, object obj)
{
GestureCount++;
switch (gr.GestureType)
{
case GestureType.SingleTap:
Gestures.Insert(0, string.Format("Gesture:{0} param is {1}", gr.GestureType, obj));
break;
case GestureType.DoubleTap:
Gestures.Insert(0, string.Format("Gesture:{0} param is {1}", gr.GestureType, obj));
break;
case GestureType.LongPress:
Gestures.Insert(0, string.Format("Gesture:{0} param is {1}", gr.GestureType, obj));
break;
case GestureType.Swipe:
Gestures.Insert(0,string.Format("Gesture:{0} Direction: {1} param is {2}",gr.GestureType,gr.Direction,obj));
break;
}
}
/// <summary>
/// Tests to see if a gesture's action can execute
/// </summary>
/// <param name="result">The final <see cref="GestureResult"/></param>
/// <param name="param">The Gesture Paramater cast to T before calling the function</param>
/// <returns>true if the action can execute,false othewise</returns>
public bool CanExecuteGesture(GestureResult result, object param)
{
return(_canexecute == null || _canexecute(result, param as T));
}
/// <summary>
/// Virtual aync funciton that the user can override to provide
/// any custom functionality required.
/// </summary>
/// <param name="gesture"><see cref="GestureResult"/></param>
/// <param name="annoyingbaseobjectthing"></param>
/// <returns></returns>
protected virtual async Task Execute(GestureResult gesture, object annoyingbaseobjectthing)
{
await _asyncExecute(gesture, annoyingbaseobjectthing as T);
}
/// <summary>
/// Tests to see if a gesture's action can execute
/// </summary>
/// <param name="result">The final <see cref="GestureResult"/></param>
/// <param name="annoyingbaseobjectthing">The Gesture Paramater</param>
/// <returns>true if the action can execute,false othewise</returns>
public bool CanExecuteGesture(GestureResult result, object annoyingbaseobjectthing)
{
return(_canexecute == null || _canexecute(result, annoyingbaseobjectthing as T));
}
private void SatisfyInterest(GestureInterest gi,GestureResult args)
{
var commandparam = gi.GestureParameter??args.StartView.BindingContext??BindingContext;
if (gi.GestureCommand != null && gi.GestureCommand.CanExecuteGesture(args, gi.GestureParameter))
gi.GestureCommand.ExecuteGesture(args,commandparam);
var handler = GestureRecognized;
if (handler != null)
{
handler(args.StartView, args);
}
}
/// <summary>
/// Used by <see cref="GesturesContentView"/>.
/// </summary>
/// <param name="gesture">The resulting gesture<see cref="GestureResult"/></param>
/// <returns>True if the gesture was handled,false otherwise</returns>
internal bool ProcessGesture(GestureResult gesture)
{
//Check the view stack first
if (ExcludeChildren && gesture.ViewStack != null && gesture.ViewStack.Count != 0 && _viewInterests.All(x => x.View != gesture.ViewStack[0])) return false;//The innermost (source) is not an actual interested view
var interestedview = InterestedView(gesture.Origin);
if (interestedview == null) return false;
gesture.StartView = interestedview.View;
//Check for perfect matches first
var interest = interestedview.Interests.Where(x => x.GestureType == gesture.GestureType &&
(
(x.Direction & Directionality.HorizontalMask) == (gesture.Direction & Directionality.HorizontalMask) &&
(x.Direction & Directionality.VerticalMask) == (gesture.Direction & Directionality.VerticalMask))
).ToList();
if (!interest.Any())
{
//Check for match on the dominant axis
var horizontaldirection = gesture.HorizontalDistance < gesture.VerticalDistance
? Directionality.None :gesture.Direction & Directionality.HorizontalMask;
var verticaldirection = gesture.HorizontalDistance < gesture.VerticalDistance
? gesture.Direction & Directionality.VerticalMask
: Directionality.None;
//Swap in the new direction so the user knows what the final match was
gesture.Direction = horizontaldirection | verticaldirection;
interest =interestedview.Interests.Where(x =>x.GestureType == gesture.GestureType &&
(x.Direction & Directionality.HorizontalMask)== horizontaldirection &&
(x.Direction & Directionality.VerticalMask) == verticaldirection).ToList();
}
//Winnow out the swipe gestures to match on either a perfect direction match (ie Up,Left) or based on the dominant axis
//Is there one or more interest int this gesture?
if (!interest.Any()) return false;
var final = interest.First();
//Finish setting up our gestureresult
gesture.Origin=new Point(Math.Max(gesture.Origin.X-interestedview.View.X,0),Math.Max(gesture.Origin.Y-interestedview.View.Y,0));
SatisfyInterest(final,gesture);
return true;
}
