The code can be modified as follows to add inline edit capability: set editor to 'textfield' for the Name column, set grid's selType to 'cellmodel', and instantiate CellEditing plugin.
_createGrid: function(stories) {
this.add({
xtype: 'rallygrid',
store: Ext.create('Rally.data.custom.Store', {
data: stories,
pageSize: 100
}),
columnCfgs: [
{
text: 'Formatted ID', dataIndex: 'FormattedID', xtype: 'templatecolumn',
tpl: Ext.create('Rally.ui.renderer.template.FormattedIDTemplate')
},
{
text: 'Name', dataIndex: 'Name', editor: 'textfield'
}
//other columns...
],
selType: 'cellmodel',
plugins: [
Ext.create('Ext.grid.plugin.CellEditing', {
clicksToEdit: 1
})
]
});
}
Please see documentation on Ext.grid.plugin.CellEditing here