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Maps API for JavaScript

China specific
Maps API for JavaScript Developer's Guide

H.util.ContextItem

Class Summary

Extends: H.util.EventTarget

This class represents contextual information/action.

[ For full details, see the Class Details ]

Property Summary

Table 1. Properties
Properties

static SEPARATOR : {H.util.ContextItem}

This constant represents the separator for the context item.

Method Summary

Table 2. Methods
Methods

getLabel () : {string}

This method retrieves the label of the context item.

setLabel (label) : {H.util.ContextItem}

This method sets the context item label.

isDisabled () : {boolean}

This method retrieves a value indicating whether the given context item is disabled or not.

setDisabled (disabled) : {H.util.ContextItem}

This method enables/disables the context item.

addEventListener (type, handler, opt_capture, opt_scope)

This method adds a listener for a specific event.

removeEventListener (type, handler, opt_capture, opt_scope)

This method removes a previously added listener from the EventTarget instance.

dispatchEvent (evt)

This method dispatches an event on the EventTarget object.

dispose ()

This method removes listeners from the given object. Classes that extend EventTarget may need to override this method in order to remove references to DOM Elements and additional listeners.

addOnDisposeCallback (callback, opt_scope)

This method adds a callback which is triggered when the EventTarget object is being disposed.

Class Description

This class represents contextual information/action.

Example 

// Enable map events such as "contextmenu"
var events = new H.mapevents.MapEvents(map);

// Show default controls as well as the Context Menu control
var ui = H.ui.UI.createDefault(map, defaultLayers, 'en-US');

// Add 'Zoom in' context menu item
map.addEventListener('contextmenu', function(e) {
  e.items.push(new H.util.ContextItem({
  label: 'Zoom in',
  callback: function() {
    map.setZoom(map.getZoom() + 1);
  }
  }));
});

Constructor Details

H.util.ContextItem(opt_options)

Parameters:
 
opt_options:
{H.util.ContextItem.Options=} [optional]
 
An object containing the initialization properties

Property Details

static SEPARATOR: {H.util.ContextItem}

This constant represents the separator for the context item.

Method Details

getLabel () : {string}

This method retrieves the label of the context item.

Returns:
 
{string}
The label of the context item

setLabel (label) : {H.util.ContextItem}

This method sets the context item label.

Parameters:
 
label:
{string}
 
A new label for the context item
Returns:
 
{H.util.ContextItem}
An object representing the given context item

isDisabled () : {boolean}

This method retrieves a value indicating whether the given context item is disabled or not.

Returns:
 
{boolean}
true if the item is disabled, false otherwise

setDisabled (disabled) : {H.util.ContextItem}

This method enables/disables the context item.

Parameters:
 
disabled:
{boolean}
 
true to disable and false to enabled the context item
Returns:
 
{H.util.ContextItem}
An object representing the given context item

addEventListener (type, handler, opt_capture, opt_scope)

This method adds a listener for a specific event.

Note that to prevent potential memory leaks, you must either call removeEventListener or dispose on the given object when you no longer need it.

Parameters:
 
type:
{string}
 
The name of the event
handler:
{!Function}
 
An event handler function
opt_capture:
{boolean=} [optional]
 
true indicates that the method should listen in the capture phase (bubble otherwise)
opt_scope:
{Object=} [optional]
 
An object defining the scope for the handler function

removeEventListener (type, handler, opt_capture, opt_scope)

This method removes a previously added listener from the EventTarget instance.

Parameters:
 
type:
{string}
 
The name of the event
handler:
{!Function}
 
A previously added event handler
opt_capture:
{boolean=} [optional]
 
true indicates that the method should listen in the capture phase (bubble otherwise)
opt_scope:
{Object=} [optional]
 
An oject defining the scope for the handler function

dispatchEvent (evt)

This method dispatches an event on the EventTarget object.

Parameters:
 
evt:
{(H.util.Event | string)}
 
An object representing the event or a string with the event name

dispose ()

This method removes listeners from the given object. Classes that extend EventTarget may need to override this method in order to remove references to DOM Elements and additional listeners.

addOnDisposeCallback (callback, opt_scope)

This method adds a callback which is triggered when the EventTarget object is being disposed.

Parameters:
 
callback:
{!Function}
 
The callback function.
opt_scope:
{Object=} [optional]
 
An optional scope for the callback function