Created attachment 31789 [details]
A simple NBM file (around 4Kb) that installs a custom property editor for colors

Created attachment 31790 [details]
Source code for previous NBM file (around 7Kb)

I've attached a simple NBM that registers globally a PropertyEditor for Colors.
You can reproduce the issue by opening a form, selecting the background color
(use the text field for setting the color: I've not extended ExPropertyEditor,
so the ColorChooser does not set the color). Then close the form and open it
again: the PropertyEditor cannot be loaded.

Updated version to current, as this happens in NB6.0M1 too.

By the way, NB 6.0 M1 does not correctly report the exception, and the form
editor is not properly initialized.

Yes, we should fix this and load the globally registered property editors.

However you can make it work already now (in 5.0/5.5). You need to include the 
following snippet in the layer.xml file (enter your concrete package name where 
your property editor resides):

  <folder name="org-netbeans-modules-form">
    <folder name="classloader">
        <folder name="system">
            <file name="MyModuleClasses.txt">
            com.me.mypackage.**
            </file>
        </folder>
    </folder>
  </folder>


Note you should not register the property editor for common types like Color 
for which NetBeans have its own editors registered. You override the original 
property editor and break it for the whole IDE.

Fixed in trunk.

/cvs/form/src/org/netbeans/modules/form/GandalfPersistenceManager.java
new revision: 1.168; previous revision: 1.167

Note if you wanted an _additional_ editor for Color or other common type, you 
could make it available via the editor search path (in PropertyEditorManager).

Regarding...
  <folder name="org-netbeans-modules-form">
    <folder name="classloader">
        <folder name="system">
            <file name="MyModuleClasses.txt">
            com.me.mypackage.**
            </file>
        </folder>
    </folder>
  </folder>

Seems to work correctly, but if I extend ExPropertyEditor then
   public void attachEnv(PropertyEnv propertyEnv)
is never invoked :-(, so I think the change to GandalfPersistenceManager is the
way to go. I'll try that as soon as possible (1/2 weeks)

Regarding overriding NetBeans' property editors... I'm registering through
FormPropertyEditorManager (I'm cheating, I know) so the user can choose which
editor to use (from the combobox). That way I avoid overriding NetBeans'
built-in editors.

Thanks for the change,
Antonio

If you use FormPropertyEditorManager then you definitely need to register your 
name space in the xml. My fix is related only to use of 
java.beans.PropertyEditorManager (which is independent on form module).

I see no reason why your ExPropertyEditor should not work. Please double-check, 
or send us a test case. We also use ExPropertyEditor impls and they work fine. 
If your class is correctly loaded and the property editor displayed, then 
attachEnv should be called.

Just note that attachEnv might be called _after_ getCustumEditor, which might 
be confusing.

Hi,

My fault: attachEnv is being called, but if I invoke
FormPropertyEditorManager.registerEditor then the property is not modified when
using the custom editor.

The solution seems to be registering the editor through the XML snippet in
layer.xml. I don't seem to need to invoke neither
FormPropertyEditorManager.registerEditor *nor*
PropertyEditorManager.registerEditor. The XML snippet itself registers the
editor properly.

So, to summarize:
  - For common types just register the PropertyEditor using the XML snippet. Do
not use either FormPropertyEditorManager *nor* PropertyEditorManager to register
the Property Editor. The Form Editor will include the new PropertyEditor and
will *not* override existing editors. The user may still use any other older
(previously registered) editor.

So I assume this is the preferred way to enhance the Form Editor with new
PropertyEditors for common types.

I may be able to attach some simple module with a custom color editor. Shall I
do so? Just for the records?

Thanks,
Antonio

Yes please - if you can. Thanks

I was too fast stating that things were solved for me. The fact is that I was
opening a pre-existing project, with a form file that was referencing the
property editor. This is issue seems to be somewhat difficult to test. I suggest
following the next steps:

a) Clean & build the module. Cleaning is important!
b) Run the module. 
c) Create a *new* Java project (do not open a previous one as I was doing, since
the .form files may alter the test).
d) Create a new Form, and change the background color by pressing the [...]
button in the property.
e) Select the MyCustomColorEditor from the drop down box.
   e.1.) If the module Installer registers the editor using
PropertyEditorManager.registerEditor then a single MyCustomColorEditor is shown,
that works, and all the rest of editors are gone.
   e.2.) If the module Installer register the editor using
FormPropertyEditorManager.registerEditor then MyCustomColorEditor is shown
*twice*, and all the rest of editors are still there. None of the
MyCustomColorEditors (two of them) seems to work. The editor appears twice
depending on the XML snippet in layer.xml
f) Close the form. (The form is saved to a .form file)
g) Open the form again. The form is read from the .form file. 
    g.1) If the editor was registered from step e.1) then everything works.
    g.2.) If the editor was registered from step e.2) then the form may be
loaded only if the XML snippet is in place in layer.xml


I'll be attaching the source code for the test in a minute. Please contact me if
 I've not explained myself correctly.

Cheers,
Antonio

Created attachment 32847 [details]
Source code for tests, with a working getCustomEditor