Try so:
$this->widget('zii.widgets.grid.CGridView', array(
'selectableRows'=>1,
'selectionChanged'=>'function(id){
var selected_tr = $.fn.yiiGridView.getSelection(id);
$("#"+id).find("tr#"+selected_tr).css("background-color", "red");
}',
'dataProvider'=>$dataProvider,
'columns'=>array(
'title',
array(
'name'=>'authorName',
'value'=>'$data->author->username',
),
array(
'class'=>'CButtonColumn',
),
),
));
Is that what you want?