extjs 表格复选框禁用,该怎么处理

extjs 表格复选框禁用

JScript code

//-------------------------------------Grid为单行选择模式       //var sm = new Ext.grid.RowSelectionModel({ singleSelect: true });       //---------------------------------------Grid为带复选框的模式       var sm = new Ext.grid.CheckboxSelectionModel({ dataIndex: "QY_ZHILBOID" });       //---------------------------------------列头       var cm = new Ext.grid.ColumnModel([            new Ext.grid.RowNumberer({ header: "", width: 20, sortable: true }),            sm,            { header: "煤矿<br/>&nbsp", dataIndex: "MINGC_MK", width: 100, sortable: true },{ header: "批次<br/>&nbsp", dataIndex: "PICH", windh: 30 }