lib/Ext/Container.js
function(component) {
        if (Ext.isObject(component)) {
            component = component.getItemId();
        }

        return this.getItems().get(component);
    }
function(component) {
        if (Ext.isObject(component)) {
            component = component.getItemId();
        }

        return this.getItems().get(component);
    }
Examines this container's `{@link #property-items}` property
and gets a direct child component of this container.
@param {String/Number} component This parameter may be any of the following:

- {String} : representing the `itemId`
or `{@link Ext.Component#getId id}` of the child component.
- {Number} : representing the position of the child component
within the `{@link #property-items}` property.

For additional information see {@link Ext.util.MixedCollection#get}.
@return {Ext.Component} The component (if found).