Prevent unnecessary recursion into a slection in the navigation

SVN: 27184

openbis-ipad/openBIS/openBIS/CISDOBMasterViewController.m

@@ -157,7 +157,7 @@
     CISDOBIpadEntity *object = [self.openBisModel objectAtIndexPath: indexPath];
     cell.textLabel.text = object.summaryHeader;
     cell.detailTextLabel.text = object.summary;
-    if ([object.childrenPermIds count] > 0) {
+    if ([self.openBisModel entityHasChildren: object]) {
         cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
     } else {
         cell.accessoryType = UITableViewCellAccessoryNone;

openbis-ipad/openBIS/openBIS/CISDOBOpenBisModel.h

@@ -52,7 +52,8 @@
 
 //! Select the object and return it
 - (CISDOBIpadEntity *)selectObjectAtIndexPath:(NSIndexPath *)indexPath;
-- (BOOL)selectionHasChildren; //!< Return YES if the selected object is a group (has children)
+- (BOOL)selectionHasChildren; //!< Return YES if the selected object has children in the selection context
+- (BOOL)entityHasChildren:(CISDOBIpadEntity *)entity; //!< Return YES if the entity has children in the selection context.
 
 // Actions
 - (BOOL)insertNewObjectOrError:(NSError **)error; //!< Return YES if operation succeeded

openbis-ipad/openBIS/openBIS/CISDOBOpenBisModel.m

@@ -82,7 +82,16 @@
 
 - (BOOL)selectionHasChildren
 {
-    return [_selectedObject.childrenPermIds count] > 0;
+    if (!_selectedObject) return NO;
+    return [self entityHasChildren: _selectedObject];
+}
+
+- (BOOL)entityHasChildren:(CISDOBIpadEntity *)entity
+{
+    // In this case we are already looking at the children. No need to allow circular recursion.
+    if (_parentModel && [entity isEqual: _parentModel.selectedObject]) return NO;
+    
+    return [entity.childrenPermIds count] > 0;
 }
 
 #pragma mark - Actions