BasemapLayerList
require(["esri/widgets/BasemapLayerList"], function(BasemapLayerList) { /* code goes here */ });esri/widgets/BasemapLayerListThe BasemapLayerList widget provides a way to display a list of Basemap layers and switch on/off their visibility. Base layers and reference layers are divided into separate sections. When editing is enabled, layers can be reordered by dragging and dropping between the lists and the title can be edited.
BasemapLayerList is very similar to our LayerList widget. See below samples for code inspiration:
Sample - LayerList widget
Sample - LayerList widget with actions
var basemapLayerList = new BasemapLayerList({
view: view
});
// Adds the widget below other elements in the top left corner of the view
view.ui.add(basemapLayerList, {
position: "top-left"
});Constructors
- new BasemapLayerList(properties)
- Parameter:properties Objectoptional
See the properties for a list of all the properties that may be passed into the constructor.
Example:// typical usage var BasemapLayerList = new BasemapLayerList({ view: view });
Property Overview
| Name | Type | Summary | Class | |
|---|---|---|---|---|
| Collection<ListItem> | A collection of ListItems representing the baseLayers. more details | more details | BasemapLayerList | |
| Function | Specifies a function that accesses each ListItem representing a base layer. more details | more details | BasemapLayerList | |
| String | The current basemap's title. more details | more details | BasemapLayerList | |
| String|HTMLElement | The ID or node representing the DOM element containing the widget. more details | more details | Widget | |
| String | The name of the class. more details | more details | Accessor | |
| Boolean | When | more details | Widget | |
| Boolean | Indicates whether the basemap’s title, layer order and layer grouping can be edited by the user. more details | more details | BasemapLayerList | |
| String | The widget's default CSS icon class. more details | more details | iconClass | |
| String | The unique ID assigned to the widget when the widget is created. more details | more details | Widget | |
| String | The widget's default label. more details | more details | BasemapLayerList | |
| Collection<ListItem> | A collection of ListItems representing the referenceLayers. more details | more details | BasemapLayerList | |
| Function | Specifies a function that accesses each ListItem representing a reference layer. more details | more details | BasemapLayerList | |
| Collection<ListItem> | A collection of selected ListItems representing basemap layers selected by the user. more details | more details | BasemapLayerList | |
| Boolean | Option for enabling status indicators, which indicate whether or not each layer is loading resources. more details | more details | BasemapLayerList | |
| MapView|SceneView | A reference to the MapView or SceneView. more details | more details | BasemapLayerList | |
| BasemapLayerListViewModel | The view model for this widget. more details | more details | BasemapLayerList |
Property Details
- baseItems Collection<ListItem>
A collection of ListItems representing the baseLayers.
- baseListItemCreatedFunction Function
Specifies a function that accesses each ListItem representing a base layer. Each list item's modifiable properties can be updated within. Actions can be added to list items using the actionsSections property of the ListItem.
Example:var bmLayerList = new BasemapLayerList({ view: view, editingEnabled: true, baseListItemCreatedFunction: function(event){ baseListItem = event.item; if(baseListItem.title === "World Imagery_01"){ // clean up title baseListItem.title = "World Imagery"; // open the baseList item baseListItem.open = true; } } })
- basemapTitle String
The current basemap's title.
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.
When
true, this property indicates whether the widget has been destroyed.
- editingEnabled Boolean
Indicates whether the basemap’s title, layer order and layer grouping can be edited by the user. Any edits made will only be shown locally and will not be saved.
- Default Value:false
Example:// to enable editing basemapLayerList.editingEnabled = true;
- iconClass Stringinner
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 String
The widget's default label.
- referenceItems Collection<ListItem>
A collection of ListItems representing the referenceLayers.
- referenceListItemCreatedFunction Function
Specifies a function that accesses each ListItem representing a reference layer. Each list item's modifiable properties can be updated within. Actions can be added to list items using the actionsSections property of the ListItem.
- selectedItems Collection<ListItem>readonly
A collection of selected ListItems representing basemap layers selected by the user.
- statusIndicatorsVisible Boolean
Option for enabling status indicators, which indicate whether or not each layer is loading resources.
- Default Value:true
Example:// enable status indicators for all layers listed in BasemapLayerList basemapLayerList.statusIndicatorVisible = true;
- viewModel BasemapLayerListViewModel
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 BasemapLayerListViewModel class to access all properties and methods on the widget.
Method Overview
| Name | Return Type | Summary | Class | |
|---|---|---|---|---|
| String | A utility method used for building the value for a widget's | more details | Widget | |
Destroys the widget instance. more details | more details | Widget | ||
| Boolean | Emits an event on the instance. more details | more details | Widget | |
| Boolean | Indicates whether there is an event listener on the instance that matches the provided event name. more details | more details | Widget | |
| Object | Registers an event handler on the instance. more details | more details | Widget | |
Widget teardown helper. more details | more details | Widget | ||
This method is primarily used by developers when implementing custom widgets. more details | more details | Widget | ||
| Object | This method is primarily used by developers when implementing custom widgets. more details | more details | Widget | |
Renders widget to the DOM immediately. more details | more details | Widget | ||
This method is primarily used by developers when implementing custom widgets. more details | more details | Widget | ||
Triggers the trigger-action event and executes the given action or action toggle. more details | more details | BasemapLayerList |
Method Details
A utility method used for building the value for a widget's
classproperty. This aids in simplifying CSS class setup.Parameter:repeatable The class names.
Returns:Type 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.
Parameters:type StringThe name of the event.
event ObjectoptionalThe event payload.
Returns:Type Description Boolean trueif 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.
Registers an event handler on the instance. Call this method to hook an event with a listener.
Parameters:A event type, or an array of event types, to listen for.
listener FunctionThe function to call when the event is fired.
Returns:Type Description Object Returns an event handler with a remove()method that can 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(handles)inherited
Widget teardown helper. Any handles added to it will be automatically removed when the widget is destroyed.
Parameter:handles 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.
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.
- triggerAction(action, item)
Triggers the trigger-action event and executes the given action or action toggle.
Parameters:action ActionButton|ActionToggleThe action to execute.
item ListItemAn item associated with the action.
Event Overview
| Name | Type | Summary | Class | |
|---|---|---|---|---|
{action: ActionButton,ActionToggle,item: ListItem} | Fires after the user clicks on an action or action toggle inside the BasemapLayerList widget. more details | more details | BasemapLayerList |
Event Details
- trigger-action
Fires after the user clicks on an action or action toggle inside the BasemapLayerList widget. This event may be used to define a custom function to execute when particular actions are clicked.
- Properties:
- action ActionButton|ActionToggle
The action clicked by the user.
item ListItemAn item associated with the action.