Locking tab on the Class form

Information on this tab is used only for concrete classes that do not belong to a class group.

Select the Allow Locking box to cause the system to lock open instances of the class, that is, instances copied from the database into the clipboard using the Obj-Open method or similar methods.

For concrete classes that do belong to a class group, leave this tab blank. The Lock field on the Class Group form controls locking for all the classes in the group. See Concepts — Understanding object locking.

Field Description
Key Name Optional. Leave this array blank in all but rare circumstances. If this field is blank, the Keys properties from the General tab of this form is used to define a lock string.

In unusual situations, you can define a non-standard lock for the class by listing here the properties that together define the lock key. The value of these properties (rather than the properties on the General tab) are concatenated to form a lock key for the instance. The resulting value may at runtime apply to multiple open objects, locking not only this object but all other open objects (even objects of other classes) with the same completed lock key value.

Key Caption Optional. Not used.
Allow Locking? For concrete classes, select this box except in rare situations. Select to allow the system to lock open instances of the class when the Obj-Open or Obj-Open-By-Handle method specifies locking.

However, for concrete classes derived from the Rule- base class, leave cleared. To restrict updates to individual rules to one developer at a time, use rule check-out (by updating the RuleSet to allow checkout, and updating the Operator ID to enable checkout), not locks.

If this class is part of a class group, the Lock field on the class group form supersedes this Allow Locking? value.

If selected, a user cannot save or delete an instance within the scope of this class group unless that user holds a lock on the object. Typically, activities acquire locks when they open an instance to the clipboard.

Note: If Allow locking? is selected, then when you use the Obj-Open, Obj-Open-by-Handle or Obj-Refresh-and-Lock method in an activity to open an instance within the scope of this class group (with intent to update and save the instance), select the Lock check box parameter for the method.