The HeatmapSlider widget is intended for authoring and exploring data-driven visualizations in any layer that can be rendered with a HeatmapRenderer. At a minimum you must set the stops property of the widget. The stops are used to render a color gradient on the track of the slider.
See the image below for a summary of the configurable options available on this slider.
The fromRendererResult method can be used to conveniently create this slider from the result of the createRenderer method.
const params = {
layer: layer,
basemap: map.basemap,
view: view
};
let rendererResult = null;
heatmapRendererCreator
.createRenderer(params)
.then(function(response) {
rendererResult = response;
layer.renderer = response.renderer;
const slider = slider.fromRendererResult(rendererResult);
colorSlider.container = "slider";
})
.catch(function(error) {
console.log("there was an error: ", error);
});
This slider should be used to update the colorStops in a HeatmapRenderer. It is the responsibility of the app developer to set up event listeners on this slider to update the renderer's color stops.
// when the user slides the handle(s), update the renderer
// with the updated color stops
slider.on(["thumb-change", "thumb-drag"], function() {
const renderer = layer.renderer.clone();
renderer.colorStops = slider.stops;
layer.renderer = renderer;
});
Constructors
-
new HeatmapSlider(properties)
-
Parameterproperties Objectoptional
See the properties for a list of all the properties that may be passed into the constructor.
Exampleconst slider = new HeatmapSlider({ stops: [ { color: "rgba(63, 40, 102, 0)", ratio: 0 }, { color: "#472b77", ratio: 0.083 }, { color: "#4e2d87", ratio: 0.166 }, { color: "#563098", ratio: 0.249 }, { color: "#5d32a8", ratio: 0.332 }, { color: "#6735be", ratio: 0.415 }, { color: "#7139d4", ratio: 0.498 }, { color: "#7b3ce9", ratio: 0.581 }, { color: "#853fff", ratio: 0.664 }, { color: "#a46fbf", ratio: 0.747 }, { color: "#c29f80", ratio: 0.83 }, { color: "#e0cf40", ratio: 0.913 }, { color: "#ffff00", ratio: 1 } ] });
Property Overview
Name | Type | Summary | Class |
---|---|---|---|
String|HTMLElement | The ID or node representing the DOM element containing the widget. more details | Widget | |
String | The name of the class. more details | Accessor | |
String | The unique ID assigned to the widget when the widget is created. more details | Widget | |
String | The HeatmapSlider widget's default label. more details | HeatmapSlider | |
HeatmapColorStop[] | The colorStops of the HeatmapRenderer to associate with the slider. more details | HeatmapSlider | |
HeatmapSliderViewModel | The view model for the Heatmap widget. more details | HeatmapSlider | |
Boolean | 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" });
-
The name of the class. The declared class name is formatted as
esri.folder.className
.
-
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 Stringreadonly
-
The HeatmapSlider widget's default label.
-
stops HeatmapColorStop[]
-
The colorStops of the HeatmapRenderer to associate with the slider.
Examplesslider.stops = [ { color: "rgba(63, 40, 102, 0)", ratio: 0 }, { color: "#472b77", ratio: 0.083 }, { color: "#4e2d87", ratio: 0.166 }, { color: "#563098", ratio: 0.249 }, { color: "#5d32a8", ratio: 0.332 }, { color: "#6735be", ratio: 0.415 }, { color: "#7139d4", ratio: 0.498 }, { color: "#7b3ce9", ratio: 0.581 }, { color: "#853fff", ratio: 0.664 }, { color: "#a46fbf", ratio: 0.747 }, { color: "#c29f80", ratio: 0.83 }, { color: "#e0cf40", ratio: 0.913 }, { color: "#ffff00", ratio: 1 } ];
slider.stops = layer.renderer.colorStops;
-
viewModel HeatmapSliderViewModel
-
The view model for the Heatmap widget. This class contains all the logic (properties and methods) that controls this widget's behavior. See the esri/widgets/smartMapping/HeatmapSlider/HeatmapliderViewModel class to access all properties and methods on the HeatmapSlider 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 |
---|---|---|---|
Adds one or more handles which are to be tied to the lifecycle of the object. more details | Accessor | ||
String | A utility method used for building the value for a widget's | Widget | |
Destroys the widget instance. more details | Widget | ||
Boolean | Emits an event on the instance. more details | Widget | |
HeatmapSlider | A convenience function used to create a HeatmapSlider widget instance from the result of the heatmapRendererCreator.createRenderer() method. more details | HeatmapSlider | |
Boolean | Indicates whether there is an event listener on the instance that matches the provided event name. more details | Widget | |
Boolean | Returns true if a named group of handles exist. more details | Accessor | |
Boolean |
| Widget | |
Boolean |
| Widget | |
Boolean |
| Widget | |
Object | Registers an event handler on the instance. more details | Widget | |
Adds one or more handles which are to be tied to the lifecycle of the widget. more details | Widget | ||
This method is primarily used by developers when implementing custom widgets. more details | Widget | ||
Removes a group of handles owned by the object. more details | Accessor | ||
Object | This method is primarily used by developers when implementing custom widgets. more details | Widget | |
Renders widget to the DOM immediately. more details | Widget | ||
This method is primarily used by developers when implementing custom widgets. more details | Widget | ||
Promise |
| Widget |
Method Details
-
addHandles(handleOrHandles, groupKey)inheritedSince: ArcGIS Maps SDK for JavaScript 4.25
-
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.when( () => !view.updating, () => { wkidSelect.disabled = false; }, { once: true } ); this.addHandles(handle); // Destroy the object this.destroy();
ParametershandleOrHandles WatchHandle|WatchHandle[]Handles marked for removal once the object is destroyed.
groupKey *optionalKey identifying the group to which the handles should be added. All the handles in the group can later be removed with Accessor.removeHandles(). If no key is provided the handles are added to a default group.
-
A utility method used for building the value for a widget's
class
property. This aids in simplifying CSS class setup.Parameterrepeatable The class names.
ReturnsType Description String The computed class name. 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.
-
Emits an event on the instance. This method should only be used when creating subclasses of this class.
Parameterstype StringThe name of the event.
event ObjectoptionalThe event payload.
ReturnsType Description Boolean true
if a listener was notified
-
-
A convenience function used to create a HeatmapSlider widget instance from the result of the heatmapRendererCreator.createRenderer() method.
ParameterrendererResult HeatmapRendererResultThe result object from the heatmapRendererCreator.createRenderer() method.
ReturnsType Description HeatmapSlider Returns a HeatmapSlider instance. This will not render until you assign it a valid container. Examplelet params = { layer: layer, basemap: map.basemap, field: "POP", view: view }; heatmapRendererCreator .createRenderer(params) .then(function(response) { // set generated renderer on the layer and add it to the map rendererResult = response; layer.renderer = response.renderer; let slider = HeatmapSlider.fromHeatmapRendererResult(response); slider.container = "slider"; });
-
Indicates whether there is an event listener on the instance that matches the provided event name.
Parametertype StringThe name of the event.
ReturnsType Description Boolean Returns true if the class supports the input event.
-
Since: ArcGIS Maps SDK for JavaScript 4.25
-
Returns true if a named group of handles exist.
ParametergroupKey *optionalA group key.
ReturnsType Description Boolean Returns true
if a named group of handles exist.Example// Remove a named group of handles if they exist. if (obj.hasHandles("watch-view-updates")) { obj.removeHandles("watch-view-updates"); }
-
Since: ArcGIS Maps SDK 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.ReturnsType Description Boolean Indicates whether creating an instance of the class has been fulfilled (either resolved or rejected).
-
Since: ArcGIS Maps SDK 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.ReturnsType Description Boolean Indicates whether creating an instance of the class has been rejected.
-
Since: ArcGIS Maps SDK 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.ReturnsType 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.
ParametersAn event or an array of events to listen for.
listener FunctionThe function to call when the event fires.
ReturnsType 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. Exampleview.on("click", function(event){ // event is the event handle returned after the event fires. console.log(event.mapPoint); });
-
own(handleOrHandles)inheritedSince: ArcGIS Maps SDK for JavaScript 4.24
-
Adds one or more handles which are to be tied to the lifecycle of the widget. The handles will be removed when the widget is destroyed.
const handle = reactiveUtils.when( () => !view.updating, () => { wkidSelect.disabled = false; }, { once: true} ); this.own(handle); // Handle gets removed when the widget is destroyed.
ParameterhandleOrHandles WatchHandle|WatchHandle[]Handles marked for removal once the widget is destroyed.
-
postInitialize()inherited
-
This method is primarily used by developers when implementing custom widgets. Executes after widget is ready for rendering.
-
removeHandles(groupKey)inheritedSince: ArcGIS Maps SDK for JavaScript 4.25
-
Removes a group of handles owned by the object.
ParametergroupKey *optionalA group key or an array or collection of group keys to remove.
Exampleobj.removeHandles(); // removes handles from default group obj.removeHandles("handle-group"); obj.removeHandles("other-handle-group");
-
This method is primarily used by developers when implementing custom widgets. It must be implemented by subclasses for rendering.
ReturnsType 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.
-
Since: ArcGIS Maps SDK 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.Parameterscallback FunctionoptionalThe function to call when the promise resolves.
errback FunctionoptionalThe function to execute when the promise fails.
ReturnsType Description Promise Returns a new promise for the result of callback
.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 |
---|---|---|---|
{index: Number,oldValue: Number,type: "thumb-change",value: Number} |
Fires when a user changes the value of a thumb via arrow keys and keyboard editing of the label on the widget. more details |
HeatmapSlider | |
{index: Number,state: "start"|"drag",type: "thumb-drag",value: Number} |
Fires when a user drags a thumb on the widget. more details |
HeatmapSlider |
Event Details
-
thumb-change
-
Fires when a user changes the value of a thumb via arrow keys and keyboard editing of the label on the widget.
- Properties
-
index Number
The 0-based index of the thumb emitting the event.
oldValue NumberThe former value of the thumb before the change was made.
type StringThe type of the event.
The value is always "thumb-change".
value NumberThe value of the thumb when the event is emitted.
Exampleslider.on("thumb-change", function() { const renderer = layer.renderer.clone(); renderer.colorStops = slider.stops; layer.renderer = renderer; });
-
thumb-drag
-
Fires when a user drags a thumb on the widget.
- Properties
-
index Number
The 0-based index of the thumb emitting the event.
state StringThe state of the drag.
Possible Values:"start"|"drag"
type StringThe type of the event.
The value is always "thumb-drag".
value NumberThe value of the thumb when the event is emitted.
Exampleslider.on("thumb-drag", function() { const renderer = layer.renderer.clone(); renderer.colorStops = slider.stops; layer.renderer = renderer; });