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

        var dockedItems = this.getDockedItems(),
            ln = dockedItems.length,
            item, i;

        if (Ext.isNumber(component)) {
            return dockedItems[component];
        }

        for (i = 0; i < ln; i++) {
            item = dockedItems[i];
            if (item.id == component) {
                return item;
            }
        }

        return false;
    }
function(component) {
        if (Ext.isObject(component)) {
            component = component.getItemId();
        }

        var dockedItems = this.getDockedItems(),
            ln = dockedItems.length,
            item, i;

        if (Ext.isNumber(component)) {
            return dockedItems[component];
        }

        for (i = 0; i < ln; i++) {
            item = dockedItems[i];
            if (item.id == component) {
                return item;
            }
        }

        return false;
    }
Finds a docked item of this container using a reference, `id `or an `index` of its location
in {@link #getDockedItems}.
@param {String/Number} component The `id` or `index` of the component to find.
@return {Ext.Component/Boolean} The docked component, if found.