Ext.require(['Ext.tree.*', 'Ext.data.*', 'Ext.window.MessageBox']);Ext.define("Ext.ux.comboboxtree", {extend : "Ext.form.field.Picker",requires : ["Ext.tree.Panel"],initComponent : function() {        var self = this;Ext.apply(self, {fieldLabel : self.fieldLabel,labelWidth : self.labelWidth// pickerAlign : "tl"//悬浮到其上面});self.callParent();    },createPicker : function() {        var self = this;        var store = Ext.create('Ext.data.TreeStore', {proxy : {type : 'ajax',?url : self.storeUrl},sorters : [{property : 'leaf',direction : 'ASC'}, {property : 'text',direction : 'ASC'}]                });self.picker = new Ext.tree.Panel({height : 300,autoScroll : true,floating : true,focusOnToFront : false,shadow : true,ownerCt : this.ownerCt,useArrows : true,store : store,rootVisible : false});self.picker.on({beforehide : function(p) {                        var records = self.picker.getView().getChecked(), names = [];Ext.Array.each(records, function(rec) {names.push(rec.get('text'));                                });// Ext.MessageBox.show({                        // title : 'Selected Nodes',                        // msg : names.join('
'),                        // icon : Ext.MessageBox.INFO                        // });                        // alert(names.join(','));self.setValue(names.join(','));p.setVisible(true);// 隐藏树}                });        return self.picker;    },alignPicker : function() {// override the original method because otherwise the height of        // the treepanel would be always 0var me = this, picker, isAbove, aboveSfx = '-above';        if (this.isExpanded) {picker = me.getPicker();            if (me.matchFieldWidth) {// Auto the height (it will be constrained by min and                // max width) unless there are no records to display.picker.setWidth(me.bodyEl.getWidth());            }            if (picker.isFloating()) {picker.alignTo(me.inputEl, "", me.pickerOffset);// ""->tl                // add the {openCls}-above class if the picker was                // aligned above                // the field due to hitting the bottom of the viewportisAbove = picker.el.getY() < me.inputEl.getY();me.bodyEl[isAbove ? 'addCls' : 'removeCls'](me.openCls+ aboveSfx);picker.el[isAbove ? 'addCls' : 'removeCls'](picker.baseCls+ aboveSfx);            }        }    }});Ext.onReady(function() {            var com = Ext.create("Ext.ux.comboboxtree", {storeUrl : 'check-nodes.json',width : 270,fieldLabel : '行政区划',labelWidth : 60,renderTo : 'tree-div'});        });http://www.sencha.com/forum/showthread.php?132328-CLOSED-ComboBox-using-Grid-instead-of-BoundList