gridpanel - Download file on row click, in extjs4 -

i have grid panel column if click downalod file associate row. in extjs 2 define new renderer function return return string format of url this:

function downaloadfile(value, metadata, record, rowindex, colindex, store) if (record.data.id){       return string.format('<b><a href="<c:url value='/filedownload.action?id={0}'/>" title="<fmt:message key='button.table.file.download.tooltip'/>"><img src="<c:url value="/icons/icon_download.gif"/>"/></a></b>',record.data.id); } 

this syntax not rigth in extjs4.2 because string.format ext.string.format when made change nothig happens.

i try use new actioncolumn in column definition in way:

{                         xtype:'actioncolumn',                         text: "download",                          width:80,                         items: [{                                 sortable: false,                                  align:'center',                                 iconcls: 'download_icon',                                 hreftarget: '_blank',                                 handler: function(grid, rowindex, colindex) {                                     var rec = reportpanel.getstore().getat(rowindex);                                     return ext.string.format('<b><a href="<c:url value='/filedownload.action?id={0}'/>" title="download.tooltip"></a></b>',rec.id);                                 }                         }]                 } 

but wrong because javascript debugger doesn't made type of error. in advance.

the handler property of actioncolumn (witch renders icon, or series of icons in grid cell, , offers scoped click handler each icon) documented as:

a function called when icon clicked.

consider using templatecolumn (witch renders value processing model's data using configured xtemplate) instead , passing tpl property.