AreaMeasurement2DViewModel

Property Overview

Property Details

geodesicDistanceThreshold Number

When the coordinate system is projected (other than web mercator) then perimeters less than this threshold will be computed planimetrically. Otherwise areas will be computed geodetically.

Default Value:100000

Example:

// To set the threshold at 10 km
let measurementWidget = new AreaMeasurement2D({
  viewModel: {
    view: view,
    geodesicDistanceThreshold: 10000
  }
});

measurement Objectreadonly

The area and perimeter of the measurement polygon in square meters and meters respectively.

Properties:

area Number The area (m²).

perimeter Number The perimeter (m).

geometry Polygon Measurement area.

Example:

// After creating and adding the AreaMeasurement2D widget
let measurementWidget = new AreaMeasurement2D({
  view: view
});
view.ui.add(measurementWidget, "top-right");

// Raw measurements (in meters) can be accessed from this property
measurementWidget.watch("viewModel.measurement", function(measurement) {
  console.log(
     "Area: ", measurement.area,
     "Perimeter: ", measurement.perimeter
  );
});

measurementLabel Objectreadonly

This property returns the locale specific representation of the area and perimeter. Areas and perimeters are rounded to two decimal places. Areas are sourced from the measurement property (in square meters) and converted to the user defined units/system.

Properties:

area Number The area (m²).

perimeter Number The perimeter (m).

Example:

// After creating and adding the AreaMeasurement2D widget
let measurementWidget = new AreaMeasurement2D({
  view: view
});
view.ui.add(measurementWidget, "top-right");

// Measurement labels can be accessed from this property
measurementWidget.watch("viewModel.measurementLabel", function(label) {
  console.log(
     "Area: ", label.area,
     "Perimeter: ", label.perimeter
  );
});

state Stringreadonly

The ViewModel's state.

Value	Description
disabled	not ready yet
ready	ready for measuring
measuring	measuring has started
measured	measuring has finished

Possible Values:"disabled"|"ready"|"measuring"|"measured"

Default Value:disabled

Example:

// To display the state of the AreaMeasurement2D widget
let measurementWidget = new AreaMeasurement2D({
  view: view
});
measurementWidget.watch("viewModel.state", function(state){
  console.log("Current state: ", state);
});

unit SystemOrAreaUnit

Unit system (imperial, metric) or specific unit used for displaying the area values. Possible values are listed in unitOptions.

Example:

// To create the AreaMeasurement2D widget that displays area in square US feet
let measurementWidget = new AreaMeasurement2D({
  viewModel: {
    view: view,
    unit: "square-us-feet"
  }
});

// To display the current measurement unit
console.log('Current unit: ', measurementWidget.viewModel.unit);

unitOptions SystemOrAreaUnit[]

List of available units and unit systems (imperial, metric) for displaying the area values. By default, the following units are included: metric, imperial, square-inches, square-feet, square-us-feet, square-yards, square-miles, square-meters, square-kilometers, acres, ares, hectares. Possible unit values can only be a subset of this list.

Example:

// To display the available units to the console
let measurementWidget = new AreaMeasurement2D({
  view: view
});
console.log('All units: ', measurementWidget.viewModel.unitOptions.join(", "));

view MapView

The view from which the widget will operate.

Example:

// To create the AreaMeasurement2D widget with the view property
let measurementWidget = new AreaMeasurement2D({
  viewModel: {
    view: view
  }
});

Method Overview

Method Details

clear()

Since: ArcGIS API for JavaScript 4.16

Clears the current measurement.

start()

Since: ArcGIS API for JavaScript 4.16

Starts a new measurement.

Example:

const areaMeasurement2DViewModel = new AreaMeasurement2DViewModel({
  view: view,
  unit: "square-yards"
});

await areaMeasurement2DViewModel.start();