protected override void OnPreviewMouseMove(MouseEventArgs e)
{
if (this.IsMouseCaptured)
{
// Get the new mouse position.
Point mouseDragCurrentPoint = e.GetPosition(this.ScrollBoard);
// Determine the new amount to scroll.
Point delta = new Point(
(mouseDragCurrentPoint.X > this.mouseDragStartPoint.X) ?
-(mouseDragCurrentPoint.X - this.mouseDragStartPoint.X) :
(this.mouseDragStartPoint.X - mouseDragCurrentPoint.X),
(mouseDragCurrentPoint.Y > this.mouseDragStartPoint.Y) ?
-(mouseDragCurrentPoint.Y - this.mouseDragStartPoint.Y) :
(this.mouseDragStartPoint.Y - mouseDragCurrentPoint.Y));
// Scroll to the new position.
ScrollBoard.ScrollToHorizontalOffset(this.scrollStartOffset.X + delta.X);
ScrollBoard.ScrollToVerticalOffset(this.scrollStartOffset.Y + delta.Y);
}
base.OnPreviewMouseMove(e);
}
// Panning MemoBoard
void OnPanMemoBoard(object sender, PanUpdatedEventArgs e)
{
AbsoluteLayout PannedObject = (AbsoluteLayout)sender;
switch (e.StatusType)
{
case GestureStatus.Started:
StatusLabel.Text = "Panning MemoBoard";
break;
case GestureStatus.Running:
PannedObject.TranslationX
= memoBoard.Offset.X + e.TotalX * PannedObject.Scale;
PannedObject.TranslationY
= memoBoard.Offset.Y + e.TotalY * PannedObject.Scale;
break;
case GestureStatus.Completed:
// Store the translation applied during the pan
memoBoard.Offset.X = PannedObject.TranslationX;
memoBoard.Offset.Y = PannedObject.TranslationY;
// Update Display Position
memoBoard.Display.X = memoBoard.OffsetMax.X - PannedObject.TranslationX;
memoBoard.Display.Y = memoBoard.OffsetMax.Y - PannedObject.TranslationY;
// If dx1, dy1 > 0, memoBoard should be expanded to Left and Up
double dx1 = PannedObject.TranslationX - memoBoard.OffsetMax.X;
double dy1 = PannedObject.TranslationY - memoBoard.OffsetMax.Y;
// If dx2, dy2 > 0, memoBoard should be expanded to Right and Down
double dx2 = memoBoard.Display.X + memoBoard.OriginalW
- PannedObject.WidthRequest;
double dy2 = memoBoard.Display.Y + memoBoard.OriginalH
- PannedObject.HeightRequest;
//- (PannedObject.TranslationY + PannedObject.Height);
Label2.Text = PannedObject.TranslationY.ToString();
//Label3.Text = string.Format("(dx, dy) = ( {0:0.00} , {1:0.00} )", dx, dy);
//Label2.Text = string.Format("e.Totoal X, Y = ( {0:0.00} , {1:0.00} )",
// e.TotalX, e.TotalY);
// Expand MemoBoard
if (dx1 > 0) // expand to Left
{
PannedObject.WidthRequest = PannedObject.Width + dx1;
memoBoard.Display.X = 0;
#if BoxDisplay
// Green BoxView
box3.TranslationX = PannedObject.WidthRequest - 10;
#endif
}
else // dx1 <= 0
{
#if BoxDisplay
// Green BoxView
box3.TranslationX = PannedObject.Width - 10;
#endif
if (dx2 > 0) // expand to Right
{
PannedObject.WidthRequest =
memoBoard.Display.X + memoBoard.OriginalW;
}
}
if (dy1 > 0) // expand to Up
{
PannedObject.HeightRequest = PannedObject.Height + dy1;
memoBoard.Display.Y = 0;
#if BoxDisplay
// Green BoxView
box3.TranslationY = PannedObject.HeightRequest - 10;
#endif
}
else // dy1 <= 0
{
#if BoxDisplay
// Green BoxView
box3.TranslationY = PannedObject.Height - 10;
#endif
//if (PannedObject.TranslationY + PannedObject.Height
//< memoBoard.Display.Y + memoBoard.OriginalH)
if (dy2 > 0) // expand to Down
{
PannedObject.HeightRequest =
memoBoard.Display.Y + memoBoard.OriginalH;
}
}
#if BoxDisplay
// Red BoxView
box1.TranslationX = memoBoard.Display.X;
box1.TranslationY = memoBoard.Display.Y;
// Blue BoxView
box2.TranslationX = memoBoard.Display.X + memoBoard.OriginalW - 15;
box2.TranslationY = memoBoard.Display.Y + memoBoard.OriginalH - 15;
#endif
//Label2.Text = string.Format("MemoBoard Size = ( {0:0.0} , {1:0.0} )",
// PannedObject.Width, PannedObject.Height);
Label3.Text = string.Format("Display X, Y = ( {0:0.0} , {1:0.0} )",
memoBoard.Display.X, memoBoard.Display.Y);
// Shift MemoBoard to Left and Up
if (dx1 > 0)
{
memoBoard.OffsetMax.X = PannedObject.TranslationX;
ScrollBoard.ScrollToAsync(PannedObject.TranslationX,
ScrollBoard.ScrollY, false);
}
if (dy1 > 0)
{
memoBoard.OffsetMax.Y = PannedObject.TranslationY;
ScrollBoard.ScrollToAsync(ScrollBoard.ScrollX,
PannedObject.TranslationY, false);
}
//Label2.Text = string.Format("OffsetMax = ( {0:0.0} , {1:0.0} )",
// memoBoard.OffsetMax.X, memoBoard.OffsetMax.Y);
// Shift all Memos and Arrows
foreach (Memo memo in Memos)
{
if (dx1 > 0)
{
memo.Body.TranslationX += dx1;
}
if (dy1 > 0)
{
memo.Body.TranslationY += dy1;
}
memo.Offset.X = memo.Body.TranslationX;
memo.Offset.Y = memo.Body.TranslationY;
foreach (Arrow arrow in memo.Arrows)
{
if (dx1 > 0)
{
arrow.Body.TranslationX += dx1;
}
if (dy1 > 0)
{
arrow.Body.TranslationY += dy1;
}
UpdateArrow(arrow);
}
}
StatusLabel.Text = "";
break;
}
Label1.Text = string.Format("(X, Y) = ( {0:0.00} , {1:0.00} )",
PannedObject.TranslationX, PannedObject.TranslationY);
//Label2.Text = string.Format("e.Total = ( {0:0.00} , {1:0.00} )",
// e.TotalX, e.TotalY);
}
// Panning Memo, and Update the Memo and the Arrows linked it
void OnPanMemo(object sender, PanUpdatedEventArgs e)
{
ContentView PannedObject = (ContentView)sender;
Memo PannedMemo = (Memo)WhichObject(PannedObject);
switch (e.StatusType)
{
case GestureStatus.Started:
PannedObject.BackgroundColor = Color.Black;
StatusLabel.Text = "Panning Memo";
break;
case GestureStatus.Running:
PannedObject.TranslationX
= PannedMemo.Offset.X + e.TotalX * PannedObject.Scale;
PannedObject.TranslationY
= PannedMemo.Offset.Y + e.TotalY * PannedObject.Scale;
foreach (Arrow arrow in PannedMemo.Arrows)
{
UpdateArrow(arrow);
}
Label1.Text = string.Format("Memo Position (X, Y) = ( {0:0.0} , {1:0.0} )",
PannedObject.TranslationX, PannedObject.TranslationY);
Label2.Text = string.Format("Memo Moved (dX, dY) = ( {0:0.0} , {1:0.0} )",
e.TotalX, e.TotalY);
break;
case GestureStatus.Completed:
PannedObject.BackgroundColor = Color.Gray;
// Store the translation applied during the pan
PannedMemo.Offset.X = PannedObject.TranslationX;
PannedMemo.Offset.Y = PannedObject.TranslationY;
#if !MemoBoardPan
// If thie object is moved out of the ScrollBoard, expand the ScrollBoard
if (PannedMemo.Offset.X + PannedObject.Width > MemoBoard.Width) // expand to Right
{
MemoBoard.WidthRequest = MemoBoard.Width +
PannedMemo.Offset.X + PannedObject.Width - MemoBoard.Width + 10;
}
if (PannedMemo.Offset.Y + PannedObject.Height > MemoBoard.Height) // expand to
{
MemoBoard.HeightRequest = MemoBoard.Height +
PannedMemo.Offset.Y + PannedObject.Height - MemoBoard.Height + 10;
}
if (PannedMemo.Offset.X < 0)
{
double dx = (-PannedMemo.Offset.X) + 10;
MemoBoard.WidthRequest = MemoBoard.Width + dx;
ScrollBoard.ScrollToAsync(dx, ScrollBoard.ScrollY, false);
// Shift all Memos and Arrows
foreach (Memo memo in Memos)
{
memo.Body.TranslationX += dx;
memo.Offset.X = memo.Body.TranslationX;
foreach (Arrow arrow in memo.Arrows)
{
arrow.Body.TranslationX += dx;
UpdateArrow(arrow);
}
}
}
if (PannedMemo.Offset.Y < 0)
{
double dy = (-PannedMemo.Offset.Y) + 10;
MemoBoard.HeightRequest = MemoBoard.Height + dy;
ScrollBoard.ScrollToAsync(ScrollBoard.ScrollX, dy, false);
// Shift all Memos and Arrows
foreach (Memo memo in Memos)
{
memo.Body.TranslationY += dy;
memo.Offset.Y = memo.Body.TranslationY;
foreach (Arrow arrow in memo.Arrows)
{
arrow.Body.TranslationY += dy;
UpdateArrow(arrow);
}
}
}
#endif
StatusLabel.Text = "Pan Completed";
break;
// If this Memo is removed, Cancel event is raised
//case GestureStatus.Canceled:
// DisplayAlert("", "Canceled", "Ok");
// break;
}
}
