Chain of Command–next() gotcha

Be careful when using Chain of Command not to place the next() call in a condition.

Here is an example.

Create a class extension for a form. Call the method init() but place it in an “if” condition. Something like this.

public void init()
{
  if (this.args() && this.args().record())
  {
    //do something before

    next init(); //this is inside the “if” condition

    //do something after
  }
}

The compiler will not error or give you a warning. However, at run time you will get a misleading error.

In my case I got this. “Error executing code: Wrong argument type for function.”

Having a look at Event viewer (Folder: AX-XppRuntime), it gave me a little more info. At least I know the class that was calling it. I searched for any customization.

I found an extension class PurchReqCreate_Extension. I was able to eye ball and figure out the problem. Taking next() outside the “if” condition.

Rewrote the same:

public void init()
{
  if (this.args() && this.args().record())
  {
    //do something before
  }

  next init();

}