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97 lines
2.5 KiB
TypeScript
97 lines
2.5 KiB
TypeScript
/**
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* Contains the VirtualArray class, which is an advanced array like class that helps loading items on demand.
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* @module "data/virtual-array"
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*/ /** */
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import * as observable from "../observable";
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import * as observableArray from "../observable-array";
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/**
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* Provides event args for "changed" event.
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*/
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export interface ChangedData<T> extends observableArray.ChangedData<T> {
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//
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}
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/**
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* Change types (Add, Delete, Update, Splice).
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*/
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export class ChangeType extends observableArray.ChangeType {
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//
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}
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/**
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* Advanced array like class that helps loading items on demand.
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*/
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export class VirtualArray<T> extends observable.Observable {
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/**
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* String value used when hooking to change event.
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*/
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public static changeEvent: string;
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/**
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* String value used when hooking to itemsLoading event.
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*/
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public static itemsLoadingEvent: string;
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constructor(arrayLength?: number);
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/**
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* Gets or sets length for the virtual array.
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*/
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length: number;
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/**
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* Gets or sets load size for the virtual array.
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*/
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loadSize: number;
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/**
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* Returns item at specified index.
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*/
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getItem(index: number): T;
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/**
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* Sets item at specified index.
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*/
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setItem(index: number, value: T): void;
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/**
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* Loads items from an array starting at index.
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*/
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load(index: number, items: T[]): void;
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/**
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* A basic method signature to hook an event listener (shortcut alias to the addEventListener method).
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* @param eventNames - String corresponding to events (e.g. "propertyChange"). Optionally could be used more events separated by `,` (e.g. "propertyChange", "change").
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* @param callback - Callback function which will be executed when event is raised.
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* @param thisArg - An optional parameter which will be used as `this` context for callback execution.
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*/
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on(eventNames: string, callback: (data: observable.EventData) => void, thisArg?: any);
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/**
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* Raised when still not loaded items are requested.
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*/
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on(event: "itemsLoading", callback: (args: ItemsLoading) => void, thisArg?: any);
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/**
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* Raised when a change occurs.
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*/
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on(event: "change", callback: (args: ChangedData<T>) => void, thisArg?: any);
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}
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/**
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* Event args for "itemsLoading" event.
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*/
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export interface ItemsLoading extends observable.EventData {
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/**
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* Start index.
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*/
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index: number;
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/**
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* Number of items to load.
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*/
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count: number;
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}
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