ExtJS4下拉树组件

/**
*下拉树类(Jelly)
*/
Ext.define('Redm.commons.TreeCombox', {
    extend: 'Ext.form.field.Picker',
    xtype: 'treecombox',
    triggerCls: Ext.baseCSSPrefix + 'form-arrow-trigger',
    config: {
        displayField: null,
        columns: null,
        rootVisible: true,
        selectOnTab: true,
        firstSelected: false,
        maxPickerWidth: 300,
        maxPickerHeight: 360,
        minPickerHeight: 100
    },
    editable: false,
    initComponent: function() {
        var me = this;
        me.callParent(arguments);
        this.addEvents('select');
        me.store.on('load', me.onLoad, me);

    },
    createPicker: function() {
        var me = this,
            picker = Ext.create('Ext.tree.Panel', {
                store: me.store,
                floating: true,
                hidden: true,
                width: me.maxPickerWidth,
                displayField: me.displayField,
                columns: me.columns,
                maxHeight: me.maxTreeHeight,
                shadow: false,
                rootVisible: me.rootVisible,
                manageHeight: false,
                listeners: {
                    itemclick: Ext.bind(me.onItemClick, me)
                },
                viewConfig: {
                    listeners: {
                        render: function(view) {
                            view.getEl().on('keypress', me.onPickerKeypress, me);
                        }
                    }
                }
            }),
            view = picker.getView();

        view.on('render', me.setPickerViewStyles, me);
        if (Ext.isIE9 && Ext.isStrict) {
            view.on('highlightitem', me.repaintPickerView, me);
            view.on('unhighlightitem', me.repaintPickerView, me);
            view.on('afteritemexpand', me.repaintPickerView, me);
            view.on('afteritemcollapse', me.repaintPickerView, me);
        }
        return picker;
    },
    setPickerViewStyles: function(view) {
        view.getEl().setStyle({
            'min-height': this.minPickerHeight + 'px',
            'max-height': this.maxPickerHeight + 'px'
        });
    },
    repaintPickerView: function() {
        var style = this.picker.getView().getEl().dom.style;
        style.display = style.display;
    },
    alignPicker: function() {
        var me = this,
            picker;

        if (me.isExpanded) {
            picker = me.getPicker();
            if (me.matchFieldWidth) {
                picker.setWidth(this.picker.getWidth());
            }
            if (picker.isFloating()) {
                me.doAlign();
            }
        }
    },
    onItemClick: function(view, record, node, rowIndex, e) {
        this.selectItem(record);
    },
    onPickerKeypress: function(e, el) {
        var key = e.getKey();

        if(key === e

补充：web前端 , JavaScript ,