TImageEnView.OnMeasure

Declaration

property OnMeasure: TIEMeasureEvent;

Description

Occurs whenever the user is measuring using miMeasureLength, miMeasureRect, miMeasurePath or miMeasureEllipse.
It is useful to assign styling to the ruler layer, or to display the current measurement value.

Parameter	Description
Sender	The TImageEnView control
MeasureType	What is being measured, e.g. iemLength or iemRectArea, iemEllipseArea
MeasureLayer	The layer that displays the measurement. Will be a TIELineLayer if MeasureLayer = iemLength, TIEPolylineLayer for MeasureLayer = iemPath, TIEAngleLayer for MeasureLayer = iemAngle, or TIETextLayer for iemRectArea or iemEllipseArea
Value	The current value of the measurement (e.g. the length of the line or area of the ellipse)
Units	The current units of the measurement. This value can be modified

Example

procedure TForm1.ImageEnView1Measure(Sender: TObject; MeasureType: TIEMeasureType; MeasureLayer: TIELayer; Len: Double; var Units: TIEUnits);
begin
  // MEASURE LENGTHS
  if MeasureLayer is TIELineLayer then
    with TIELineLayer( MeasureLayer ) do
    begin
      LineColor := clWhite;
      LineWidth := 3;
      LabelFont.Color := clBlue;
    end
  else
  // MEASURE AREAS
  if MeasureLayer is TIETextLayer then
    with TIETextLayer( MeasureLayer ) do
    begin
      BorderColor := clBlack;
      BorderWidth := 3;
      FillColor    := clSilver;
      Font.Color   := clBlue;
      Transparency := 128;
    end;
end;

TImageEnView.OnMeasure