/// <summary>
/// Updates the measurements and message shown on the popup based on the in-progress
/// geometry, including the passed-in point
/// </summary>
/// <param name="mapPoint"></param>
private void updateMeasurements(MapPoint mapPoint)
{
if (_currentDrawVertices != null)
{
double length = 0d;
double area = 0d;
string measurement1 = null;
string measurement2 = null;
switch (AssociatedObject.DrawMode)
{
case DrawMode.Freehand:
// Copy the set of vertices and add the passed-in point to it
PointCollection tmpPts = _currentDrawVertices.Clone();
tmpPts.Add(mapPoint.Clone());
// Check whether a polyline or polygon is being drawn
FreehandDrawMode freehandeMode = AttachedProperties.GetFreehandDrawMode(AssociatedObject);
if (freehandeMode == FreehandDrawMode.Polyline)
{
// Get the length of the line and update the measurement text
Polyline line = new Polyline()
{
SpatialReference = _currentDrawVertices[0].SpatialReference
};
line.Paths.Add(tmpPts);
length = line.Length();
measurement1 = string.Format(Strings.LengthLabelFormat, getLengthString(length));
}
else if (freehandeMode == FreehandDrawMode.Polygon)
{
// Close the polygon by duplicating the first vertex and adding it to the end
tmpPts.Add(tmpPts[0].Clone());
Polygon polygon = new Polygon {
SpatialReference = _currentDrawVertices[0].SpatialReference
};
polygon.Rings.Add(tmpPts);
// Get the perimeter of the polygon and update the measurement text
length = polygon.Perimeter();
measurement1 = string.Format(Strings.PerimeterLabelFormat, getLengthString(length));
}
break;
case DrawMode.Polyline:
// Create a line containing the segement of the polyline currently being drawn.
// First, get the most recently drawn point
tmpPts = new PointCollection();
tmpPts.Add(_currentDrawVertices[_currentDrawVertices.Count - 1].Clone());
// Add the passed-in point
tmpPts.Add(mapPoint.Clone());
// Create a polyline with the points
Polyline polyline = new Polyline()
{
SpatialReference = _currentDrawVertices[0].SpatialReference
};
polyline.Paths.Add(tmpPts);
// Calculate the length and update the segment measurement text
length = polyline.Length();
measurement1 = string.Format(Strings.SegmentLengthLabelFormat, getLengthString(length));
// If there already two or more points in the polyline, calculate total length as well
if (_currentDrawVertices.Count > 1)
{
// Copy the current set of vertices and add the passed-in point
tmpPts = _currentDrawVertices.Clone();
tmpPts.Add(mapPoint.Clone());
// Create a polyline with the points
polyline = new Polyline()
{
SpatialReference = _currentDrawVertices[0].SpatialReference
};
polyline.Paths.Add(tmpPts);
// Get the length
length = polyline.Length();
}
// Update measurement text showing the total length of the line
measurement2 = string.Format(Strings.TotalLengthLabelFormat, getLengthString(length));
break;
case DrawMode.Rectangle:
// Create an envelope from the initial point and the passed-in piont
Envelope env = new Envelope(_currentDrawVertices[0], mapPoint)
{
SpatialReference = mapPoint.SpatialReference
};
// Get the perimeter and area of the envelope
length = env.Perimeter();
area = env.Area();
// Update the measurement text
measurement1 = string.Format(Strings.PerimeterLabelFormat, getLengthString(length));
measurement2 = string.Format(Strings.AreaLabelFormat, getAreaString(area));
break;
case DrawMode.Circle:
case DrawMode.Ellipse:
// Get the initial (center) point and the current point
tmpPts = new PointCollection();
tmpPts.Add(_currentDrawVertices[0].Clone());
//tmpPts.Add(_currentDrawVertices[_currentDrawVertices.Count - 1].Clone());
tmpPts.Add(mapPoint.Clone());
// Create a line with the points
polyline = new Polyline()
{
SpatialReference = _currentDrawVertices[0].SpatialReference
};
polyline.Paths.Add(tmpPts);
// Calculate the length of the line. This is the radius.
length = polyline.Length();
// For circles, this info is sufficient to calculate perimeter anda area
if (AssociatedObject.DrawMode == DrawMode.Circle)
{
// Calculate perimeter (circumference) and area
double circumference = 2 * length * Math.PI;
area = Math.PI * Math.Pow(length, 2);
// Display measures
measurement1 = string.Format(Strings.PerimeterLabelFormat, getLengthString(circumference));
measurement2 = string.Format(Strings.AreaLabelFormat, getAreaString(area));
}
else // Ellipse
{
// insufficient info for perimeter & area, so just display radius
measurement1 = string.Format(Strings.RadiusLabelFormat, getLengthString(length));
}
break;
case DrawMode.Polygon:
// Can only calculate perimeter and area if there are already two or more
// vertices in the polygon
if (_currentDrawVertices.Count > 1)
{
// Copy the existing vertices and add the passed-in point
tmpPts = _currentDrawVertices.Clone();
tmpPts.Add(mapPoint.Clone());
// Create a polygon from the points
Polygon p = new Polygon()
{
SpatialReference = mapPoint.SpatialReference
};
p.Rings.Add(tmpPts);
// Calculate the perimeter as well as the area
length = p.Perimeter();
area = p.Area();
// Update measurement text
measurement1 = string.Format(Strings.PerimeterLabelFormat, getLengthString(length));
measurement2 = string.Format(Strings.AreaLabelFormat, getAreaString(area));
}
break;
default:
break;
}
// Update the draw popup with the measurement text
if (measurement1 != null)
{
PopupText = _drawInstructions + "\n" + measurement1;
}
if (measurement2 != null)
{
PopupText += "\n" + measurement2;
}
}
}
/// <summary>
/// Sets the freehand drawing mode of the Draw object
/// </summary>
public static void SetFreehandDrawMode(Draw draw, FreehandDrawMode mode)
{
draw.SetValue(FreehandDrawModeProperty, mode);
}
/// <summary>
/// Sets the freehand drawing mode of the Draw object
/// </summary>
public static void SetFreehandDrawMode(Draw draw, FreehandDrawMode mode)
{
draw.SetValue(FreehandDrawModeProperty, mode);
}
