How to make sure that a form is only opened once?

Question

Is it possible to make sure a user only can open one instance of a specific form, for instance CustTrans from CustTable? Modal form is not an option. Some sort of Singleton pattern?

Answer 1

You can use the global cache for this, more info on MSDN: http://msdn.microsoft.com/en-us/library/aa891830.aspx. However a lot of the time the use of the global cache is a sign of bad design.

You can use the global cache to implement a singleton pattern as demonstrated here: http://www.axaptapedia.com/Singleton_pattern

Also consider alternative solutions to your problem, for example the one used on inventory journals. When you open the lines for a journal, it is marked as "in use" so no one else can open that particular journal.

Side note: I believe what you are trying to achieve is a bit of an anti-pattern. Dynamics AX uses dynalinks to link forms together. All of this functionality will be lost if you implement this.