# Class Ext.dd.ScrollManager

Package: | Ext.dd
Defined In: | ScrollManager.js
Class: | ScrollManager
Extends: | Object

Provides automatic scrolling of overflow regions in the page during drag operations.

The ScrollManager configs will be used as the defaults for any scroll container registered with it, but you can also override most of the configs per scroll container by adding a `ddScrollConfig` object to the target element that contains these properties: hthresh, vthresh, increment and frequency. Example usage:

    var el = Ext.get('scroll-ct');
    el.ddScrollConfig = {
        vthresh: 50,
        hthresh: -1,
        frequency: 100,
        increment: 200
    };
    Ext.dd.ScrollManager.register(el);

Note: This class uses "Point Mode" and is untested in "Intersect Mode".
This class is a singleton and cannot be created directly.

## Public Properties

Property | Defined By
--- | ---
| animDuration : Number The animation duration in seconds - MUST BE less than Ext.dd.ScrollManager.frequency! (defaults to .4) | ScrollManager
| animate : Boolean True to animate the scroll (defaults to true) | ScrollManager
| frequency : Number The frequency of scrolls in milliseconds (defaults to 500) | ScrollManager
| hthresh : Number The number of pixels from the right or left edge of a container the pointer needs to be to trigger scrolling (defaul... The number of pixels from the right or left edge of a container the pointer needs to be to trigger scrolling (defaults to 25) | ScrollManager
| increment : Number The number of pixels to scroll in each scroll increment (defaults to 50) | ScrollManager
| vthresh : Number The number of pixels from the top or bottom edge of a container the pointer needs to be to trigger scrolling (defaul... The number of pixels from the top or bottom edge of a container the pointer needs to be to trigger scrolling (defaults to 25) | ScrollManager

## Public Methods

Method | Defined By
--- | ---
| refreshCache() : void Manually trigger a cache refresh. Manually trigger a cache refresh. Parameters: None. Returns: void | ScrollManager
| register( `Mixed/Array el` ) : void Registers new overflow element(s) to auto scroll Registers new overflow element(s) to auto scroll Parameters: `el` : Mixed/Array The id of or the element to be scrolled or an array of either Returns: void | ScrollManager
| unregister( `Mixed/Array el` ) : void Unregisters overflow element(s) so they are no longer scrolled Unregisters overflow element(s) so they are no longer scrolled Parameters: `el` : Mixed/Array The id of or the element to be removed or an array of either Returns: void | ScrollManager

## Public Events

This class has no public events.