PRB: GETPEM Function Doesn't Work on Object Contained in Class

ID: Q141632

3.00b WINDOWS kbprg kbprb

The information in this article applies to:

Microsoft Visual FoxPro for Windows, version 3.0b

SYMPTOMS

Using the GETPEM() function to return any property, event, or method from any object contained within a class doesn't work unless that object is a class (other than the object's base class) unto itself.

CAUSE

When the GETPEM() function receives a class name as its first parameter, it only retrieves the event and method code associated with this class. It does not return the program code of any contained object.

RESOLUTION

To examine the properties, events, or methods of any contained object of a parent class, use the Class Designer or Class Browser.

STATUS

This behavior is by design.

MORE INFORMATION

The GETPEM() function is new to Microsoft Visual FoxPro version 3.0b. GETPEM() requires two arguments. The first argument should refer to either the object or class that contains the property, event, or method. The second argument should refer to the property, event, or method.

Steps to Reproduce Behavior

1. Create a new form and place a command button on it. In the Init event of

   the form, add this code:

   This.Command1.SetFocus

2. In the Click event of the command button, add this code:

   ThisForm.Release

3. On the File menu, click Save as Class. In the Name field, enter pemclass

   and in the File field, enter Test.

4. Exit the Form Designer. On the Tools menu, click Options, and then click

   the Forms tab. Under Template Classes, select the Form check box and
   locate the Test.vcx file. Highlight it, and click OK. Click the OK
   button on the Options page to save the change.

5. Create a new form, and note that the pemclass is now the template.

   Without making any changes, save the form as pemform. Then close it, and
   use the DO FORM command to run the form.

6. On the Tools menu, click Debug Window. Resize it so that there is

   sufficient area on both sides.

7. In the left side of the Debug window, type:

   GETPEM("pemclass","init")

   On the right side of the Debug window, the following should be
   displayed:

   This.Command1.SetFocus

NOTE: When trying to see the code under the Click event of the command button, you must realize that the Click event belongs to the command button. Therefore, you are not able to use pemclass as the left side of the argument in the GETPEM() function. The only way to get to the command button is to use object referencing from the top down. In the left side of the Debug window, type:

   GETPEM(_Screen.ActiveForm.Command1,"Click")

On the right side of the Debug window, you will see "", but you know there is a ThisForm.Release command. Because the command was put in at the class level, the only thing that is returned with the GETPEM() function is the code that was inserted at the object (or form) level, which is a null string.

There is no syntax that can be used with the GETPEM() function that can return the ThisForm.Release code from the Click event of the command button in the above example. However, if a class were created based on the command button (for example, mybutton) and the Click event at that class level contained code, then it would be possible to use this:

   GETPEM("mybutton","click")

Additional reference words: 3.00b VFoxWin KBCategory: kbprg kbprb KBSubcategory: FxprgClassoop

Keywords          : FxprgClassoop 
Version           : 3.00b
Platform          : WINDOWS