靜態unListen for a certain type of event.
The event type or array of event types.
The listener function.
可選opt_this: ObjectThe object to use as this in listener.
Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.
Listen once for a certain type of event.
The event type or array of event types.
The listener function.
可選opt_this: ObjectThe object to use as this in listener.
Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.
函數Removes an event listener using the key returned by on() or once().
Note that using the ol.Observable.unByKey static function is to
be preferred.
可選opt_values: { [k: string]: any }An object with key-value pairs.
Abstract base class; normally only used for creating subclasses and not instantiated in apps. Most non-trivial classes inherit from this.
This extends ol.Observable with observable properties, where each property is observable as well as the object as a whole.
Classes that inherit from this have pre-defined properties, to which you can
add your owns. The pre-defined properties are listed in this documentation as
'Observable Properties', and have their own accessors; for example,
ol.Map has a target property, accessed with getTarget() and
changed with setTarget(). Not all properties are however settable. There
are also general-purpose accessors get() and set(). For example,
get('target') is equivalent to getTarget().
The set accessors trigger a change event, and you can monitor this by
registering a listener. For example, ol.View has a center
property, so view.on('change:center', function(evt) {...}); would call the
function whenever the value of the center property changes. Within the
function, evt.target would be the view, so evt.target.getCenter() would
return the new center.
You can add your own observable properties with
object.set('prop', 'value'), and retrieve that with object.get('prop').
You can listen for changes on that property value with
object.on('change:prop', listener). You can get a list of all
properties with object.getProperties().
Note that the observable properties are separate from standard JS properties.
You can, for example, give your map object a title with
map.title='New title' and with map.set('title', 'Another title'). The
first will be a hasOwnProperty; the second will appear in
getProperties(). Only the second is observable.
Properties can be deleted by using the unset method. E.g. object.unset('foo').
Classdesc
Abstract base class; normally only used for creating subclasses and not instantiated in apps. Most non-trivial classes inherit from this.
This extends ol.Observable with observable properties, where each property is observable as well as the object as a whole.
Classes that inherit from this have pre-defined properties, to which you can add your owns. The pre-defined properties are listed in this documentation as 'Observable Properties', and have their own accessors; for example, ol.Map has a
targetproperty, accessed withgetTarget()and changed withsetTarget(). Not all properties are however settable. There are also general-purpose accessorsget()andset(). For example,get('target')is equivalent togetTarget().The
setaccessors trigger a change event, and you can monitor this by registering a listener. For example, ol.View has acenterproperty, soview.on('change:center', function(evt) {...});would call the function whenever the value of the center property changes. Within the function,evt.targetwould be the view, soevt.target.getCenter()would return the new center.You can add your own observable properties with
object.set('prop', 'value'), and retrieve that withobject.get('prop'). You can listen for changes on that property value withobject.on('change:prop', listener). You can get a list of all properties with object.getProperties().Note that the observable properties are separate from standard JS properties. You can, for example, give your map object a title with
map.title='New title'and withmap.set('title', 'Another title'). The first will be ahasOwnProperty; the second will appear ingetProperties(). Only the second is observable.Properties can be deleted by using the unset method. E.g. object.unset('foo').
參數: opt_values
An object with key-value pairs.
Fires
ol.ObjectEvent
Api