misc/tutorial/102_sorting.ngdoc

@@ -22,6 +22,9 @@ The sort is automatically recalculated when you edit a field (the edit feature c
 you change the data "behind the scenes" and want the sort to be recalculated, you can notify the grid that your
 data has changed by calling `gridApi.core.notifyDataChange( grid, uiGridUtils.dataChange.EDIT )`
 
+If you set a default sort, you can prevent the user from removing that sort by setting `suppressRemoveSort: true`
+for that column.  This will let the user change the direction of the sort, but take away the option to remove the sort.
+
 <example module="app">
   <file name="app.js">
     var app = angular.module('app', ['ngAnimate', 'ngTouch', 'ui.grid']);
@@ -67,7 +70,7 @@ data has changed by calling `gridApi.core.notifyDataChange( grid, uiGridUtils.da
               direction: uiGridConstants.ASC,
               priority: 0,
             },
-
+            suppressRemoveSort: true,
             sortingAlgorithm: function(a, b) {
               var nulls = $scope.grid2Api.core.sortHandleNulls(a, b);
               if( nulls !== null ) {
@@ -235,6 +238,17 @@ data has changed by calling `gridApi.core.notifyDataChange( grid, uiGridUtils.da
         gridTestUtils.expectCellValueMatch( 'grid2', 0, 0, 'Yvonne Parsons' );
         gridTestUtils.expectCellValueMatch( 'grid2', 1, 0, 'Velma Fry' );
       });
+
+      it('sort on second column can\'t be removed when cycle through header clicks', function () {
+        gridTestUtils.clickHeaderCell( 'grid2', 0 );
+        gridTestUtils.expectCellValueMatch( 'grid2', 0, 0, 'Cora Chase' );
+
+        gridTestUtils.clickHeaderCell( 'grid2', 1 );
+        gridTestUtils.expectCellValueMatch( 'grid2', 0, 0, 'Herring Pierce' );
+
+        gridTestUtils.clickHeaderCell( 'grid2', 1 );
+        gridTestUtils.expectCellValueMatch( 'grid2', 0, 0, 'Cora Chase' );
+      });
     });
 
   </file>  

src/js/core/factories/Grid.js

@@ -1496,7 +1496,7 @@ angular.module('ui.grid')
     var self = this;
 
     self.columns.forEach(function (col) {
-      if (col !== excludeCol) {
+      if (col !== excludeCol && !col.colDef.suppressRemoveSort) {
         col.sort = {};
       }
     });

test/unit/core/factories/Grid.spec.js

@@ -686,6 +686,36 @@ describe('Grid factory', function () {
 
       expect( column.sort.direction ).toEqual(uiGridConstants.ASC);
     });
+
+    it( 'if another column has a sort, that sort should be removed', function() {
+      var priorColumn = new GridColumn({ name: 'b', sort: { direction: uiGridConstants.ASC } }, 0, grid);
+      grid.columns.push( priorColumn );
+
+      grid.sortColumn( column, false );
+
+      expect( column.sort.direction ).toEqual(uiGridConstants.ASC);
+      expect( priorColumn.sort ).toEqual({});
+    });
+
+    it( 'if another column has a sort, and add is set to true, then that sort should not be removed', function() {
+      var priorColumn = new GridColumn({ name: 'b', sort: { direction: uiGridConstants.ASC } }, 0, grid);
+      grid.columns.push( priorColumn );
+
+      grid.sortColumn( column, true );
+
+      expect( column.sort.direction ).toEqual(uiGridConstants.ASC);
+      expect( priorColumn.sort ).toEqual({ direction: uiGridConstants.ASC });
+    });
+
+    it( 'if another column has a sort, and add is set to false, but that other column has suppressRemoveSort, then it shouldn\'t be removed', function() {
+      var priorColumn = new GridColumn({ name: 'b', sort: { direction: uiGridConstants.ASC }, suppressRemoveSort: true }, 0, grid);
+      grid.columns.push( priorColumn );
+
+      grid.sortColumn( column, false );
+
+      expect( column.sort.direction ).toEqual(uiGridConstants.ASC);
+      expect( priorColumn.sort ).toEqual({ direction: uiGridConstants.ASC });
+    });
   });