public override bool DispatchTouchEvent(MotionEvent e) { var index = e.ActionIndex; var action = e.ActionMasked; var pointerId = e.GetPointerId(index); switch (action & MotionEventActions.Mask) { case MotionEventActions.PointerDown: MultiTouchGesture?.Invoke(this, EventArgs.Empty); break; case MotionEventActions.Up: if ((DateTime.Now - _downTime).TotalMilliseconds < 200) { SingleTapGesture?.Invoke(this, EventArgs.Empty); } break; } switch (action) { case MotionEventActions.Down: _downTime = DateTime.Now; if (_velocityTracker == null) { _velocityTracker = VelocityTracker.Obtain(); } else { // Reset the velocity tracker back to its initial state. _velocityTracker.Clear(); } if (IfVelocityTrackerIsNull()) { return(true); } _velocityTracker.AddMovement(e); break; case MotionEventActions.Move: if (IfVelocityTrackerIsNull()) { return(true); } _velocityTracker.AddMovement(e); _velocityTracker.ComputeCurrentVelocity(Sensitivity); TryExportVelocity(_velocityTracker.GetXVelocity(pointerId), _velocityTracker.GetYVelocity(pointerId)); break; case MotionEventActions.Up: case MotionEventActions.Cancel: if (IfVelocityTrackerIsNull()) { return(true); } _velocityTracker.Recycle(); _velocityTracker = null; break; } return(true); }
public virtual bool OnTouchEvent(Android.Views.MotionEvent ev) { switch (ev.Action) { case MotionEventActions.Down: { mVelocityTracker = VelocityTracker.Obtain(); if (null != mVelocityTracker) { mVelocityTracker.AddMovement(ev); } else { Log.Info(LOG_TAG, "Velocity tracker is null"); } mLastTouchX = GetActiveX(ev); mLastTouchY = GetActiveY(ev); mIsDragging = false; break; } case MotionEventActions.Move: { float x = GetActiveX(ev); float y = GetActiveY(ev); float dx = x - mLastTouchX, dy = y - mLastTouchY; if (!mIsDragging) { // Use Pythagoras to see if drag length is larger than // touch slop mIsDragging = FloatMath.Sqrt((dx * dx) + (dy * dy)) >= mTouchSlop; } if (mIsDragging) { mListener.OnDrag(dx, dy); mLastTouchX = x; mLastTouchY = y; if (null != mVelocityTracker) { mVelocityTracker.AddMovement(ev); } } break; } case MotionEventActions.Cancel: { // Recycle Velocity Tracker if (null != mVelocityTracker) { mVelocityTracker.Recycle(); mVelocityTracker = null; } break; } case MotionEventActions.Up: { if (mIsDragging) { if (null != mVelocityTracker) { mLastTouchX = GetActiveX(ev); mLastTouchY = GetActiveY(ev); // Compute velocity within the last 1000ms mVelocityTracker.AddMovement(ev); mVelocityTracker.ComputeCurrentVelocity(1000); float vX = mVelocityTracker.GetXVelocity(0), vY = mVelocityTracker .GetYVelocity(0); // If the velocity is greater than minVelocity, call // listener if (Math.Max(Math.Abs(vX), Math.Abs(vY)) >= mMinimumVelocity) { mListener.OnFling(mLastTouchX, mLastTouchY, -vX, -vY); } } } // Recycle Velocity Tracker if (null != mVelocityTracker) { mVelocityTracker.Recycle(); mVelocityTracker = null; } break; } } return(true); }
public override bool OnTouchEvent(MotionEvent e) { if (mVelocityTracker == null) { mVelocityTracker = VelocityTracker.Obtain(); } mVelocityTracker.AddMovement(e); MotionEventActions action = e.Action; if (action == MotionEventActions.Down) { x = e.GetX(); if (IsSlided()) { dispatched = DispatchTouchEventToView(GetChildAt(0), e); } else { dispatched = DispatchTouchEventToView(GetChildAt(1), e); } } else if (action == MotionEventActions.Move) { if (dispatched) { if (IsSlided()) { DispatchTouchEventToView(GetChildAt(0), e); } else { DispatchTouchEventToView(GetChildAt(1), e); } } else { float dx = e.GetX() - x; View view = this.GetChildAt(1); int left = (int)(view.Left + dx); if (left >= 0) { view.Layout(left, view.Top, view.Width + left, view.Top + view.Height); } } x = e.GetX(); } else if (action == MotionEventActions.Cancel || action == MotionEventActions.Up) { if (dispatched) { if (IsSlided()) { DispatchTouchEventToView(GetChildAt(0), e); } else { DispatchTouchEventToView(GetChildAt(1), e); } } else { mVelocityTracker.ComputeCurrentVelocity(1000); int velocityX = (int)mVelocityTracker.GetXVelocity(0); if (velocityX > VELOCITY_X_SPEED) { SetSlided(true); } else if (velocityX < -VELOCITY_X_SPEED) { SetSlided(false); } else { View view = GetChildAt(1); if (view.Left >= view.Width / 2) { SetSlided(true); } else { SetSlided(false); } } if (mVelocityTracker != null) { try { mVelocityTracker.Recycle(); } catch { } } } } else if (!IsSlided()) { DispatchTouchEventToView(GetChildAt(1), e); } return(true); }