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InstanceCache

Package | mx.charts.chartClasses
Class | public class InstanceCache
Inheritance | InstanceCache Object

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

InstanceCache is a utility that governs the task of creating and managing a set of n object instances, where n changes frequently.

Public Properties

| Property | Defined By
--- | --- | ---
|  | count : int The number of items currently required in the cache. | InstanceCache
|  | creationCallback : Function A callback invoked when new instances are created. | InstanceCache
|  | discard : Boolean = false Determines if unneeded instances are discarded. | InstanceCache
|  | factory : IFactory A factory that generates the type of object to cache. | InstanceCache
|  | format : TextFormat A TextFormat to apply to any instances created. | InstanceCache
|  | hide : Boolean = true Determines if unneeded instances should be hidden. | InstanceCache
|  | insertPosition : int [write-only] The position of the instance in the parent's child list. | InstanceCache
|  | instances : Array [read-only] The Array of cached instances. | InstanceCache
|  | properties : Object A hashmap of properties to assign to new instances. | InstanceCache
|  | remove : Boolean = false Determines if unneeded instances should be removed from their parent. | InstanceCache

Public Methods

| Method | Defined By
--- | --- | ---
|  | InstanceCache(type:Object, parent:Object = null, insertPosition:int = -1, moduleFactory:IFlexModuleFactory = null) Constructor. | InstanceCache

Property Detail

count | property

`count:int`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

The number of items currently required in the cache.

Implementation
`public function get count():int`
`public function set count(value:int):void`

creationCallback | property |

`public var creationCallback:Function`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

A callback invoked when new instances are created. This callback has the following signature:

          function creationCallback(newInstance:Object, cache:InstanceCache):void;

discard | property |

`public var discard:Boolean = false`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

Determines if unneeded instances are discarded. If set to `true`, extra elements are discarded when the cache count is reduced. Otherwise, extra elements are kept in a separate cache and reused when the count is increased.

factory | property |

`factory:IFactory`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

A factory that generates the type of object to cache. Assigning to this discards all current instances and recreate new instances of the correct type.

Implementation
`public function get factory():IFactory`
`public function set factory(value:IFactory):void`

format | property |

`format:TextFormat`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

A TextFormat to apply to any instances created. If set, this format is applied as the current and default format for the contents of any instances created. This property is only relevant if the factory generates TextField instances.

Implementation
`public function get format():TextFormat`
`public function set format(value:TextFormat):void`

hide | property |

`public var hide:Boolean = true`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

Determines if unneeded instances should be hidden. If `true`, the `visible` property is set to `false` on each extra element when the cache count is reduced, and set to `true` when the count is increased.

This property is only relevant when the factory generates DisplayObjects. Setting this property to `true` for other factory types generates a run-time error.

insertPosition | property |

`insertPosition:int` [write-only]

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

The position of the instance in the parent's child list.

Implementation
`public function set insertPosition(value:int):void`

instances | property |

`instances:Array` [read-only]

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

The Array of cached instances. There may be more instances in this Array than currently requested. You should rely on the `count` property of the instance cache rather than the length of this Array.

Implementation
`public function get instances():Array`

properties | property |

`properties:Object`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

A hashmap of properties to assign to new instances. Each key/value pair in this hashmap is assigned to each new instance created. The property hashmap is assigned to any existing instances when set.

The values in the hashmap are not cloned; object values are shared by all instances.

Implementation
`public function get properties():Object`
`public function set properties(value:Object):void`

remove | property |

`public var remove:Boolean = false`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

Determines if unneeded instances should be removed from their parent. If `true`, the `removeChild()` method is called on the parent for each extra element when the cache count is reduced.

This property is only relevant when the factory generates DisplayObjects. Setting this property to `true` for other factory types generates a run-time error.

Constructor Detail

InstanceCache | () | Constructor

`public function InstanceCache(type:Object, parent:Object = null, insertPosition:int = -1, moduleFactory:IFlexModuleFactory = null)`

Language Version : | ActionScript 3.0

Product Version : | Flex 3

Runtime Versions : | Flash Player 9, AIR 1.1

Constructor.

Parameters

| `type:Object` — The type of object to construct. This can be either a Class or an IFactory.
| `parent:Object` (default = `null`)`` — An optional DisplayObject to add new instances to.
| `insertPosition:int` (default = `-1`)`` — Where in the parent's child list to insert instances. Set to -1 to add the children to the end of the child list.
| `moduleFactory:IFlexModuleFactory` (default = `null`)`` — The context for using embedded fonts and for finding the style manager that controls the styles for this component.

Wed Nov 15 2017, 09:50 AM +01:00