Grouping field to grid sencha gxt2

For those who have trouble making grouping on the grid. Please create a global variable for the initial declaration: Example:

private GroupingStore storeGrouping

Then in the initial grid section is added :

storeGrouping.groupBy("name_grouping");

At the bottom then added :

	final ColumnModel cm = new ColumnModel(config);  

	GroupingView view = new GroupingView();  
	view.setForceFit(true);  

	view.setGroupRenderer(new GridGroupRenderer() {  
		public String render(GroupColumnData data) {  
			String f = cm.getColumnById(data.field).getHeader();  
			String l = data.models.size() == 1 ? "Item" : "Items";  
			return f + ": " + data.group + " (" + data.models.size() + " " + l + ")";  
		}  
	});  

	EditorGrid<SaveItem> grid = new EditorGrid<SaveItem>(store, cm);  
	grid.setView(view);  
	grid.setBorders(true);

In order for the datagrid to be grouped and sorted by the beginning or alphabetical order numbers at the beginning