下拉ComboBoxGrid

   /**1.
   2.  * 下拉ComboBoxGrid
   3.  * 
   4.  * @xtype 'combogrid' 
   5.  */

ComboBoxGrid = Ext.extend(Ext.form.ComboBox, {

    gridHeight: 180,
    listAlign: 'tr-br',
    listWidth: 300,
    store: new Ext.data.SimpleStore({
        fields: [],
        data: [[]]
    }),
    resizable: false,
    // Default 
    editable: false,
    mode: 'local',
    triggerAction: 'all',
    maxHeight: 500,
    selectedClass: '',
    onSelect: Ext.emptyFn,
    emptyText: '--\u8bf7\u9009\u62e9--',
    assertValue: function () {
        this.el.dom.value = this.str==null?"":this.str;
    },

    /**
    * ---------------------------------- 
    * 单击GRID事件
    * ----------------------------------
    */
    gridClk: function (grid, rowIndex, e) {
        this.str="";
        for(var i=0;i<grid.getStore().data.items.length;i++)
        if ((grid.getStore().data.items[i].data.start!=null && grid.getStore().data.items[i].data.start!="") || (grid.getStore().data.items[i].data.end!=null && grid.getStore().data.items[i].data.end!="")) {
            this.str+=grid.getStore().data.items[i].data[this.displayField]+",";
        }
        this.str=this.str.substring(0,this.str.length-1);
       
       this.setRawValue(this.str);
//        this.setValue(grid.getStore().getAt(rowIndex).data[this.valueField]);
//        this.setRawValue(grid.getStore().getAt(rowIndex).data[this.displayField]);
//          this.setValue(grid.getStore().getAt(rowIndex).data[this.valueField]);
//        this.setValue(grid.getRecord(rowIndex).data[this.valueField]);
//        this.collapse();
       
        this.fireEvent('gridselected',  grid.getStore().getAt(rowIndex));

    },

    initLayout: function () {
        this.grid.autoScroll = true;
        this.grid.height = this.gridHeight;
        this.grid.containerScroll = false;
        this.grid.border = false;

        this.listWidth = this.grid.width + 3;
    },
    /**
    * Init
    */
    initComponent: function () {
        ComboBoxGrid.superclass.initComponent.call(this);
        this.initLayout();
        this.tplId = Ext.id();
        // overflow:auto" 
        this.tpl = '<div id="' + this.tplId + '" style="height:' + this.gridHeight
                 + ';overflow:hidden;"></div>';

        //Add Event 
        this.addEvents('gridselected');
    },

    /**
    * ------------------ 
    *  Listener 
    * ------------------
    */
    listeners: {
        'expand': {
            fn: function () {
                if (!this.grid.rendered && this.tplId) {
                    //this.initComponent(); 
                    this.initLayout();

                    this.grid.render(this.tplId);
                    this.store = this.grid.store;

                    this.store.reload();
                    if (this.store.getCount() == 0) {
                        this.store.add(new Ext.data.Record([{}]));
                    }

                    //this.grid.store.reload(); 
                    this.grid.on('rowclick', this.gridClk, this);
                }
                this.grid.show();
                //this.grid.on('rowclick', this.gridClk, this);
            }
            //single : true 
        },

        'render': {
            fn: function () {

            }
        },
        'beforedestroy': {
            fn: function (cmp) {
                this.purgeListeners();
                this.grid.purgeListeners();
            }
        },
       
        'collapse': {
            fn: function (cmp) {
                /**
                *  防止当store的记录为0时不出现下拉的状况
                */
                //debugger
                if (this.grid.store.getCount() == 0) {
                    this.store.add(new Ext.data.Record([{}]));
                }
                this.grid.stopEditing();
                this.gridClk(this.grid);
                //this.spuperclass.collapse.call(cmp);
            }
        }
    }

});

/**
* --------------------------------- 
* register:'combotree' 
* ---------------------------------
*/
Ext.reg('combogrid', ComboBoxGrid);