Fix v2 for l-lin#1160: Cannot reinitialise DataTable.

Author: rhorenov

src/angular-datatables.renderer.js

@@ -190,14 +190,16 @@ function dtNGRenderer($log, $q, $compile, $timeout, DTRenderer, DTRendererServic
                     _destroyAndCompile();
                 }
                 $timeout(function() {
-                    _alreadyRendered = true;
-                    // Ensure that prerender is called when the collection is updated
-                    // See https://github.com/l-lin/angular-datatables/issues/502
-                    DTRendererService.preRender(renderer.options);
-                    var result = DTRendererService.hideLoadingAndRenderDataTable(_$elem, renderer.options);
-                    _oTable = result.DataTable;
-                    DTInstanceFactory.copyDTProperties(result, dtInstance);
-                    defer.resolve(dtInstance);
+                    if (!_oTable) {
+                        _alreadyRendered = true;
+                        // Ensure that prerender is called when the collection is updated
+                        // See https://github.com/l-lin/angular-datatables/issues/502
+                        DTRendererService.preRender(renderer.options);
+                        var result = DTRendererService.hideLoadingAndRenderDataTable(_$elem, renderer.options);
+                        _oTable = result.DataTable;
+                        DTInstanceFactory.copyDTProperties(result, dtInstance);
+                        defer.resolve(dtInstance);
+                    }
                 }, 0, false);
             }, true);
             return defer.promise;
@@ -229,6 +231,7 @@ function dtNGRenderer($log, $q, $compile, $timeout, DTRenderer, DTRendererServic
                 _newParentScope.$destroy();
             }
             _oTable.ngDestroy();
+            _oTable = null;
             // Re-compile because we lost the angular binding to the existing data
             _$elem.html(_staticHTML);
             _newParentScope = _parentScope.$new();