private TouchEvent CreateTouchEvent(TouchEventArgs args, TouchEvent.TouchEventAction action)
{
return new TouchEvent
{
Action = action,
Id = args.Id,
TranslatedPosition = new Vector2(args.Location.X, args.Location.Y),
NonTranslatedPosition = new Vector2(args.Location.X, args.Location.Y),
TimeStamp = DateTime.Now
};
}
private void OnHandlerOnTouchUp(object sender, TouchEventArgs touchEventArgs)
{
_queuedEvents.Add(CreateTouchEvent(touchEventArgs, TouchEvent.TouchEventAction.Up));
}
private void OnHandlerOnTouchDown(object sender, TouchEventArgs args)
{
_queuedEvents.Add(CreateTouchEvent(args, TouchEvent.TouchEventAction.Down));
}
/// <summary>
/// Decode the message and create a collection of event arguments
/// </summary>
/// <remarks>
/// One Windows message can result a group of events
/// </remarks>
/// <returns>An enumerator of thr resuting events</returns>
/// <param name="hWnd">the WndProc hWnd</param>
/// <param name="msg">the WndProc msg</param>
/// <param name="wParam">the WndProc wParam</param>
/// <param name="lParam">the WndProc lParam</param>
private IEnumerable<TouchEventArgs> DecodeMessage(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam, float dpiX, float dpiY)
{
// More than one touchinput may be associated with a touch message,
// so an array is needed to get all event information.
int inputCount = User32.LoWord(wParam.ToInt32()); // Number of touch inputs, actual per-contact messages
TOUCHINPUT[] inputs; // Array of TOUCHINPUT structures
inputs = new TOUCHINPUT[inputCount]; // Allocate the storage for the parameters of the per-contact messages
try
{
// Unpack message parameters into the array of TOUCHINPUT structures, each
// representing a message for one single contact.
if (!User32.GetTouchInputInfo(lParam, inputCount, inputs, Marshal.SizeOf(inputs[0])))
{
// Get touch info failed.
throw new Exception("Error calling GetTouchInputInfo API");
}
// For each contact, dispatch the message to the appropriate message
// handler.
// Note that for WM_TOUCHDOWN you can get down & move notifications
// and for WM_TOUCHUP you can get up & move notifications
// WM_TOUCHMOVE will only contain move notifications
// and up & down notifications will never come in the same message
for (int i = 0; i < inputCount; i++)
{
TouchEventArgs touchEventArgs = new TouchEventArgs(HWndWrapper, dpiX, dpiY, ref inputs[i]);
yield return touchEventArgs;
}
}
finally
{
User32.CloseTouchInputHandle(lParam);
}
}
