Base class for objects that provide named properties with optional getter/setter control and the ability to watch for property changes
The class also provides the functionality to auto-magically manage getters and setters for object attributes/properties.
Getters and Setters should follow the format of _xxxGetter or _xxxSetter where the xxx is a name of the attribute to handle. So an attribute of "foo" would have a custom getter of _fooGetter and a custom setter of _fooSetter.
See the dojo/Stateful reference documentation for more information.
require(["dojo/Stateful", function(Stateful) {
var obj = new Stateful();
obj.watch("foo", function(){
console.log("foo changed to " + this.get("foo"));
});
obj.set("foo","bar");
});
Used across all instances a hash to cache attribute names and their getter and setter names.
Internal helper for directly changing an attribute value.
Directly change the value of an attribute on an object, bypassing any accessor setter. Also handles the calling of watch and emitting events. It is designed to be used by descendant class when there are two values of attributes that are linked, but calling .set() is not appropriate.
| Parameter | Type | Description |
|---|---|---|
| name | String | The property to set. |
| value | Mixed | The value to set in the property. |
Internal helper for directly changing an attribute value.
Private function that does a get based off a hash of names
| Parameter | Type | Description |
|---|---|---|
| name | undefined | |
| names | undefined | Hash of names of custom attributes |
Helper function for get() and set(). Caches attribute name values so we don't do the string ops every time.
| Parameter | Type | Description |
|---|---|---|
| name | undefined |
Get a property on a Stateful instance.
Get a named property on a Stateful object. The property may potentially be retrieved via a getter method in subclasses. In the base class this just retrieves the object's property.
| Parameter | Type | Description |
|---|---|---|
| name | String | The property to get. |
The property value on this Stateful instance.
require(["dojo/Stateful", function(Stateful) {
var stateful = new Stateful({foo: 3});
stateful.get("foo") // returns 3
stateful.foo // returns 3
});
Set a property on a Stateful instance
Sets named properties on a stateful object and notifies any watchers of the property. A programmatic setter may be defined in subclasses.
| Parameter | Type | Description |
|---|---|---|
| name | String | The property to set. |
| value | Object | The value to set in the property. |
The function returns this dojo.Stateful instance.
require(["dojo/Stateful", function(Stateful) {
var stateful = new Stateful();
stateful.watch(function(name, oldValue, value){
// this will be called on the set below
}
stateful.set(foo, 5);
set() may also be called with a hash of name/value pairs, ex:
stateful.set({
foo: "Howdy",
bar: 3
});
});
This is equivalent to calling set(foo, "Howdy") and set(bar, 3)
Watches a property for changes
| Parameter | Type | Description |
|---|---|---|
| name | String |
Optional Indicates the property to watch. This is optional (the callback may be the only parameter), and if omitted, all the properties will be watched |
| callback | Function | The function to execute when the property changes. This will be called after the property has been changed. The callback will be called with the |this| set to the instance, the first argument as the name of the property, the second argument as the old value and the third argument as the new value. |
An object handle for the watch. The unwatch method of this object can be used to discontinue watching this property:
var watchHandle = obj.watch("foo", callback);
watchHandle.unwatch(); // callback won't be called now