Provides a simple button that animates the View to the user's location when clicked. The view rotates according to the direction where the tracked device is heading towards. While tracking, the default button looks like the following:
You can use the view's DefaultUI to add widgets to the view's user interface via the ui property on the view. The snippet below demonstrates this.
The Track widget is not supported on insecure origins. To use it, switch your application to a secure origin, such as HTTPS. Note that localhost is considered "potentially secure" and can be used for easy testing in browsers that supports Window.isSecureContext (currently Chrome and Firefox).
As of version 4.2, the Track Button no longer displays in non-secure web apps. At version 4.1 this only applied to Google Chrome.
For additional information regarding this, visit the ArcGIS blog, Increased web API security in Google Chrome.
Known Limitation
The Track widget does not work concurrently with the Locate widget. Only one of the widgets can be used at a time.
let trackWidget = new Track({
view: view
});
view.ui.add(trackWidget, "top-left");
Constructors
-
new Track(properties)
-
Parameter:properties Objectoptional
See the properties for a list of all the properties that may be passed into the constructor.
Example:// typical usage let track = new Track({ view: view });
Property Overview
Name | Type | Summary | Class | |
---|---|---|---|---|
String|HTMLElement | more details The ID or node representing the DOM element containing the widget. | more details | Widget | |
String | more details The name of the class. | more details | Accessor | |
Object | more details The HTML5 Geolocation Position options for locating. | more details | Track | |
Boolean | more details Indicates whether the widget will automatically navigate the view to the user's position when a geolocation result is found. | more details | Track | |
GoToOverride | more details This function provides the ability to override either the MapView goTo() or SceneView goTo() methods. | more details | Track | |
Graphic | more details The graphic used to show the user's location in the view. | more details | Track | |
String | more details The widget's default CSS icon class. | more details | Track | |
String | more details The unique ID assigned to the widget when the widget is created. | more details | Widget | |
String | more details The widget's default label. | more details | Track | |
Number | more details Indicates the scale to set on the view when navigating to the position of the geolocated result once a location is returned from the track event. | more details | Track | |
Boolean | more details Indicates whether the widget is watching for new positions. | more details | Track | |
Boolean | more details Indicates whether the widget will automatically rotate to user's direction. | more details | Track | |
MapView|SceneView | more details | more details | Track | |
TrackViewModel | more details The view model for this widget. | more details | Track | |
Boolean | more details Indicates whether the widget is visible. | more details | Widget |
Property Details
-
-
The ID or node representing the DOM element containing the widget. This property can only be set once. The following examples are all valid use cases when working with widgets.
Examples:// Create the HTML div element programmatically at runtime and set to the widget's container const basemapGallery = new BasemapGallery({ view: view, container: document.createElement("div") }); // Add the widget to the top-right corner of the view view.ui.add(basemapGallery, { position: "top-right" });
// Specify an already-defined HTML div element in the widget's container const basemapGallery = new BasemapGallery({ view: view, container: basemapGalleryDiv }); // Add the widget to the top-right corner of the view view.ui.add(basemapGallery, { position: "top-right" }); // HTML markup <body> <div id="viewDiv"></div> <div id="basemapGalleryDiv"></div> </body>
// Specify the widget while adding to the view's UI const basemapGallery = new BasemapGallery({ view: view }); // Add the widget to the top-right corner of the view view.ui.add(basemapGallery, { position: "top-right" });
-
Since: ArcGIS API for JavaScript 4.7
-
The name of the class. The declared class name is formatted as
esri.folder.className
.
-
geolocationOptions Object
-
The HTML5 Geolocation Position options for locating. Refer to Geolocation API Specification for details.
- Default Value:{ maximumAge: 0, timeout: 15000, enableHighAccuracy: true }
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goToLocationEnabled Boolean
-
Indicates whether the widget will automatically navigate the view to the user's position when a geolocation result is found. Set to
false
to disable this behavior, leaving full control to the developer.- Default Value:true
-
goToOverride GoToOverrideSince: ArcGIS API for JavaScript 4.8
-
This function provides the ability to override either the MapView goTo() or SceneView goTo() methods.
Example:// The following snippet uses the Search widget but can be applied to any // widgets that support the goToOverride property. search.goToOverride = function(view, goToParams) { goToParams.options.duration = updatedDuration; return view.goTo(goToParams.target, goToParams.options); };
-
The graphic used to show the user's location in the view.
Example:let trackWidget = new Track({ view: view, // Assigns the track widget to a view graphic: new Graphic({ symbol: { type: "simple-marker" } // Overwrites the default symbol used for the // graphic placed at the location of the user when found }) });
-
iconClass StringSince: ArcGIS API for JavaScript 4.7
-
The widget's default CSS icon class.
-
The unique ID assigned to the widget when the widget is created. If not set by the developer, it will default to the container ID, or if that is not present then it will be automatically generated.
-
label StringSince: ArcGIS API for JavaScript 4.7
-
The widget's default label.
-
scale NumberSince: ArcGIS API for JavaScript 4.7
-
Indicates the scale to set on the view when navigating to the position of the geolocated result once a location is returned from the track event. If a scale value is not explicitly set, then the view will navigate to a default scale of
2500
. For 2D views the value should be within the effectiveMinScale and effectiveMaxScale.- Default Value:null
Example:mapView.watch("scale", function (currentScale){ console.log("scale: %s", currentScale); }); mapView.when(function(){ // Create an instance of the Track widget let track = new Track({ view: mapView, scale: 5000 }); // and add it to the view's UI mapView.ui.add(track, "top-left"); track.start(); track.on("track", function(trackEvent){ console.log(trackEvent); console.log("track: %s", mapView.scale); }) });
-
tracking Booleanreadonly
-
Indicates whether the widget is watching for new positions.
- Default Value:false
-
useHeadingEnabled BooleanSince: ArcGIS API for JavaScript 4.6
-
Indicates whether the widget will automatically rotate to user's direction. Set to
false
to disable this behavior.- Default Value:true
-
viewModel TrackViewModelautocast
-
The view model for this widget. This is a class that contains all the logic (properties and methods) that controls this widget's behavior. See the TrackViewModel class to access all properties and methods on the widget.
-
Indicates whether the widget is visible.
If
false
, the widget will no longer be rendered in the web document. This may affect the layout of other elements or widgets in the document. For example, if this widget is the first of three widgets associated to the upper right hand corner of the view UI, then the other widgets will reposition when this widget is made invisible. For more information, refer to the CSS display value of"none"
.- Default Value:true
Example:// Hides the widget in the view widget.visible = false;
Method Overview
Name | Return Type | Summary | Class | |
---|---|---|---|---|
String | more details A utility method used for building the value for a widget's | more details | Widget | |
more details Destroys the widget instance. | more details | Widget | ||
Boolean | more details Emits an event on the instance. | more details | Widget | |
Boolean | more details Indicates whether there is an event listener on the instance that matches the provided event name. | more details | Widget | |
Boolean | more details
| more details | Widget | |
Boolean | more details
| more details | Widget | |
Boolean | more details
| more details | Widget | |
Object | more details Registers an event handler on the instance. | more details | Widget | |
more details Adds one or more handles which are to be tied to the lifecycle of the object. | more details | Accessor | ||
more details This method is primarily used by developers when implementing custom widgets. | more details | Widget | ||
Object | more details This method is primarily used by developers when implementing custom widgets. | more details | Widget | |
more details Renders widget to the DOM immediately. | more details | Widget | ||
more details This method is primarily used by developers when implementing custom widgets. | more details | Widget | ||
more details When executed, the widget will start tracking the user's location. | more details | Track | ||
more details Stops tracking the user's location when executed. | more details | Track | ||
Promise | more details
| more details | Widget |
Method Details
-
Since: ArcGIS API for JavaScript 4.7
-
A utility method used for building the value for a widget's
class
property. This aids in simplifying CSS class setup.Parameter:repeatable The class names.
Returns:Type Description String The computed class name. - See also:
Example:// .tsx syntax showing how to set CSS classes while rendering the widget render() { const dynamicIconClasses = { [CSS.myIcon]: this.showIcon, [CSS.greyIcon]: !this.showIcon }; return ( <div class={classes(CSS.root, CSS.mixin, dynamicIconClasses)} /> ); }
-
destroy()inherited
-
Destroys the widget instance.
-
Since: ArcGIS API for JavaScript 4.5
-
Emits an event on the instance. This method should only be used when creating subclasses of this class.
Parameters:type StringThe name of the event.
event ObjectoptionalThe event payload.
Returns:Type Description Boolean true
if a listener was notified
-
Indicates whether there is an event listener on the instance that matches the provided event name.
Parameter:type StringThe name of the event.
Returns:Type Description Boolean Returns true if the class supports the input event.
-
Since: ArcGIS API for JavaScript 4.19
-
isFulfilled()
may be used to verify if creating an instance of the class is fulfilled (either resolved or rejected). If it is fulfilled,true
will be returned.Returns:Type Description Boolean Indicates whether creating an instance of the class has been fulfilled (either resolved or rejected).
-
Since: ArcGIS API for JavaScript 4.19
-
isRejected()
may be used to verify if creating an instance of the class is rejected. If it is rejected,true
will be returned.Returns:Type Description Boolean Indicates whether creating an instance of the class has been rejected.
-
Since: ArcGIS API for JavaScript 4.19
-
isResolved()
may be used to verify if creating an instance of the class is resolved. If it is resolved,true
will be returned.Returns:Type Description Boolean Indicates whether creating an instance of the class has been resolved.
-
Registers an event handler on the instance. Call this method to hook an event with a listener.
Parameters:An event or an array of events to listen for.
listener FunctionThe function to call when the event fires.
Returns:Type Description Object Returns an event handler with a remove()
method that should be called to stop listening for the event(s).Property Type Description remove Function When called, removes the listener from the event. Example:view.on("click", function(event){ // event is the event handle returned after the event fires. console.log(event.mapPoint); });
-
own(handleOrHandles)inheritedSince: ArcGIS API for JavaScript 4.24
-
Adds one or more handles which are to be tied to the lifecycle of the object. The handles will be removed when the object is destroyed.
// Manually manage handles const handle = reactiveUtils.whenOnce(() => !view.updating) .then(() => { wkidSelect.disabled = false; }); handle.remove(); // Assign a handle using own() this.own(reactiveUtils.whenOnce(() => !view.updating) .then(() => { wkidSelect.disabled = false; }));
Parameter:handleOrHandles WatchHandle|WatchHandle[]Handles marked for removal once the object is destroyed.
-
postInitialize()inherited
-
This method is primarily used by developers when implementing custom widgets. Executes after widget is ready for rendering.
-
This method is primarily used by developers when implementing custom widgets. It must be implemented by subclasses for rendering.
Returns:Type Description Object The rendered virtual node.
-
renderNow()inherited
-
Renders widget to the DOM immediately.
-
scheduleRender()inherited
-
This method is primarily used by developers when implementing custom widgets. Schedules widget rendering. This method is useful for changes affecting the UI.
-
start()
-
When executed, the widget will start tracking the user's location.
-
stop()
-
Stops tracking the user's location when executed.
-
Since: ArcGIS API for JavaScript 4.19
-
when()
may be leveraged once an instance of the class is created. This method takes two input parameters: acallback
function and anerrback
function. Thecallback
executes when the instance of the class loads. Theerrback
executes if the instance of the class fails to load.Parameters:callback FunctionoptionalThe function to call when the promise resolves.
errback FunctionoptionalThe function to execute when the promise fails.
Returns:Type Description Promise Returns a new promise for the result of callback
that may be used to chain additional functions.Example:// Although this example uses the BasemapGallery widget, any class instance that is a promise may use when() in the same way let bmGallery = new BasemapGallery(); bmGallery.when(function(){ // This function will execute once the promise is resolved }, function(error){ // This function will execute if the promise is rejected due to an error });
Event Overview
Name | Type | Summary | Class | |
---|---|---|---|---|
{position: Object} |
more details
Fires after the start() method is called and a position is found. |
more details | Track | |
{error: Error} |
more details
Fires after the start() method is called and an error is returned. |
more details | Track |
Event Details
-
track
-
Fires after the start() method is called and a position is found.
- Property:
-
position Object
Geoposition returned from the Geolocation API.