extjs - Preselect items in EXT JS 4.2 Grid -

i trying preselect items in ext grid based on value of 1 of items in data store.

in data store fetch 7 items, last item grab 'installed' boolean , use preselect items in grid.

here code have far not working...

ext.require([   'ext.grid.*',   'ext.data.*',   'ext.selection.checkboxmodel' ]);  ext.onready(function(){ ext.quicktips.init();  var sb = $('#sb_id').val();  // data store var data =  ext.create('ext.data.jsonstore', {     autoload: true,     fields: [ 'name', 'market', 'expertise', 'id', 'isfull', 'isprimary', 'installed'],     proxy: {         type: 'ajax',         url: '/opslibrary/getlibraryjsonedit',         extraparams: {             sb_id: sb         },         actionmethods: 'post'     },     sorters: [{         property: 'market',         direction: 'asc'     }, {         property: 'expertise',         direction: 'asc'     }] });  data.on('load',function(records){     ext.each(records,function(record){          var recs = [];         ext.each(record, function(item, index){              console.log(item.data);             if (item.data['installed'] == true) {                 console.log('hi!');                 recs.push(index);             }         });         //data.getselectionmodel().selectrows(recs);     }) });  // selection model var selmodel = ext.create('ext.selection.checkboxmodel', {     columns: [         {xtype : 'checkcolumn', text : 'active', dataindex : 'id'}     ],     listeners: {         selectionchange: function(value, meta, record, row, rowindex, colindex){             var selectedrecords = grid4.getselectionmodel().getselection();             var selectedparams = [];              // clear input , reset vars             $('#selected-libraries').empty();             var record = null;             var isfull = null;             var isprimary = null;              // loop through selected records             for(var = 0, len = selectedrecords.length; < len; i++){                 record = selectedrecords[i];                  // full library checked?                 isfull = record.get('isfull');                  // primary library?                 isprimary = record.get('isprimary');                  // build data object                 selectedparams.push({                     id: record.getid(),                     full: isfull,                     primary: isprimary                 });             }             // json encode object , set hidden input             $('#selected-libraries').val(json.stringify(selectedparams));         }} }); 

i trying use on.load method once store populated go , preselect items not having luck.

im python guy , don't around js sorry noobness.

any appreciated.

thanks again!

you should able like:

//create selmodel instance above data.on('load', function(st, recs) {     var installedrecords = ext.array.filter(recs, function(rec) {         return rec.get('installed');     });      //selmodel instance     selmodel.select(installedrecords); }); 

select can take array of records.
http://docs.sencha.com/extjs/4.2.1/#!/api/ext.selection.model-method-select

//data.getselectionmodel().selectrows(recs); 

didn't work because store's don't have reference selection models other way around. can selection model grid doing grid.getselectionmodel() or can use selmodel instance created

var selmodel = ext.create('ext.selection.checkboxmodel', {