private void MinuteGrab_MouseMove(object sender, MouseEventArgs e)
{
if (MinuteGrabMouseIsDown)
{
// Use positions relative to the hours display (centre is fixed with clock centre).
var mousePosition = e.GetPosition(EllipseHoursAm);
// Use the position to calculate the angle and hence required time
var a = GetAngle(mousePosition, EllipseHoursAm.Width / 2, EllipseHoursAm.Height / 2);
var minute = a / MinuteHandDegreesPerMinute;
minute = Math.Round(minute);
// The current Minute will be in the range 0 to 59
// Work out whether to transition up or down an hour
var displayMinute = DisplayTime.Minute;
if (displayMinute < 15 && minute > 45)
{
// Drag transition back an hour
minute = minute - MinutesInHour;
}
else if (displayMinute > 45 && minute < 15)
{
// Drag transition forward an hour
minute = minute + MinutesInHour;
}
DisplayTime = DisplayTime.AddMinutes(minute - DisplayTime.Minute);
}
}
private void HourGrab_MouseMove(object sender, MouseEventArgs e)
{
if (hourGrabMouseIsDown)
{
// Use positions relative to the hours display (centre is fixed with clock centre).
var mousePosition = e.GetPosition(EllipseHoursAm);
// Use the position to calculate the angle and hence required time
var a = GetAngle(mousePosition, EllipseHoursAm.Width / 2, EllipseHoursAm.Height / 2);
var hour = a / HourHandDegreesPerHour;
var minutes = Math.Round(hour * 60 % 60);
hour = Math.Floor(hour);
// The current hour will be in the range 0 to 11 (i.e. morning).
// The current display time could be morning or afternoon and if the
// display time is near midnight this could be a transition to another day.
var dayOffset = 0;
var displayHour = DisplayTime.Hour;
if (displayHour < 3 && hour > 9)
{
// Drag transition back a day
dayOffset = -1;
hour += HoursPerRevolution; // Adjust time to afternoon
}
else if (displayHour > 21 && hour < 3)
{
// Drag transition forward a day
dayOffset = 1;
}
else if (displayHour > 9 && displayHour < 12 &&
hour < 3)
{
// Drag transition between morning and afternoon
hour += HoursPerRevolution;
}
else if (displayHour >= 12)
{
// Dragging in the afternoon
// Add 12 hours if not transition to am!
if (!(displayHour < 15 && hour > 9))
{
hour += HoursPerRevolution;
}
}
DisplayTime = DisplayTime.AddHours(hour - DisplayTime.Hour);
DisplayTime = DisplayTime.AddMinutes(minutes - DisplayTime.Minute);
if (dayOffset != 0)
{
DisplayTime = DisplayTime.AddDays(dayOffset);
}
}
}
private void EllipseMinutes_MouseDown(object sender, MouseButtonEventArgs e)
{
mouseDownPoint = e.GetPosition(sender as IInputElement);
// Use the down position to calculate the angle and hence required time
var a = GetAngle(mouseDownPoint, EllipseMinutes.Width / 2, EllipseMinutes.Height / 2);
var minutes = (int)Math.Round(a / MinuteHandDegreesPerMinute);
DisplayTime = DisplayTime.AddMinutes(minutes - DisplayTime.Minute);
// Now treat as a drag
MinuteGrabMouseIsDown = true;
Mouse.Capture(MinuteHandle);
}