extjs form 动态添加组件

var win=Ext.getCmp(this.extid+'_showStartWin');
        if(!win){
    		win=Ext.create("base.source.project.demonstration.build.buildapply.view.BuildApplyPublicityStartWin",{id:this.extid+'_showStartWin',billstate:'edit',title:"列入计划"});
    	}
	    var formPanel = win.down("form");
    	    for(var i in records){
    	    	var record =  records[i].data;
    	    	var projectName = record.projectName;
    	    	var projectCode = record.projectCode;
    	    	var item= Ext.create('Ext.form.Panel', {
						    width: 750,
						    bodyPadding: 10,
						    renderTo: Ext.getBody(),
						    items:  [{layout:'hbox',
								     border:false,
								     defaults:{margins:'0 0 8 0'} ,
								     items:[{xtype:'hidden',name: 'projectCode',value:projectCode},
								     	    {xtype: 'textfield',name: 'projectName',fieldLabel: '工程名称',readOnly:true,fieldStyle:readOnlyCls,flex:1.5,value:projectName},
						                    {xtype: 'textfield',name: 'planLink',fieldLabel: '链接地址',maxLength:150,width:500,flex:3,afterLabelTextTpl:required,allowBlank:false}]
								     }]
						});
                formPanel.add(item);
           }
            formPanel.doLayout();
            win.show();