I have a strange PropertySelect problem. I have a CayenneForm with
some TextFields and some PropertySelects. The page also have a table
where users can list entries to edit. It is very much like
http://www.avoka.com:8080/click-examples/cayenne/cayenne-form-page.htm
Pressing the edit-link in the table works fine. It does a
form.setDataObject(theDataObject).
I want kind of the same functionality for the cancel-button in the
CayenneForm. If user does some editing and press cancel, the changes
are lost, but the entry is still up for editing. This how our users
want the cancel-button to work.. As this is kind of the same as the
edit-link, I have implemented this the following way:
public boolean onCancelClick() {
form.clearErrors();
form.getDataContext().rollbackChanges();
form.setDataObject(dataObject);
return true;
}
Should be almost the same thing as for the edit-button in the table
row. It is working for all fields except the PropertySelects. Those
are not reset to their original value, but set to blank.
I raised this issue on the list and it was confirmed. See
http://sourceforge.net/mailarchive/forum.php?thread_name=4A54D954-4067-4B74-ABCF-3419D6D06060%40pvv.ntnu.no&forum_name=click-user
Bug
Resolved
Major
strange PropertySelect problem
Added the following method to PropertySelect:
public void copyFrom(Object object) {
// TODO: super.copyFrom(object);
CayenneForm form = (CayenneForm) getForm();
Class doClass = form.getDataObjectClass();
String getterName = ClickUtils.toGetterName(getName());
try {
Method method = doClass.getMethod(getterName, null);
DataObject property = (DataObject) method.invoke(object, null);
if (property == null) {
setValue(null);
} else {
Object propPk = DataObjectUtils.pkForObject(property);
setValue(propPk.toString());
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
Added the following method to CayenneForm:
public void copyFrom(Object object) {
super.copyFrom(object);
final List fieldList = ClickUtils.getFormFields(this);
for (int i = 0; i < fieldList.size(); i++) {
Field field = (Field) fieldList.get(i);
// TODO: create Field.copyFrom(Object object) and make ClickUtils
// call it so that we do not need
// special handling here?
if (field instanceof PropertySelect) {
PropertySelect select = (PropertySelect) field;
select.copyFrom(object);
}
}
}
As you see, I prefer adding a method to all Fields to get rid of special cases controlled by if...instanceby..
I have seen the instanceby-if-sentence several times in click source. F.eks. ClickUtils.getFormFields that does not include Labels. Those special cases are likely to introduce bugs and makes it more difficult to expand the framework (yes, I know instanceof handles subclasses and such).