I am building a preference page extending the FieldEditorPreferencePage class. This is the code (some obvious code not displayed):
public class PreferencePage extends FieldEditorPreferencePage implements IWorkbenchPreferencePage {
public static final String PREF_KEY_1 = "checkBoxPref";
public static final String PREF_KEY_2 = "filePref";
private FileFieldEditor pathField;
private BooleanFieldEditor yesOrNoField;
private Composite pathFieldParent;
@Override
public void init(IWorkbench workbench) {
setPreferenceStore(new ScopedPreferenceStore(InstanceScope.INSTANCE, Activator.PLUGIN_ID));
}
@Override
protected void createFieldEditors() {
this.yesOrNoField = new BooleanFieldEditor(PREF_KEY_1, "Check this box!", getFieldEditorParent());
this.pathFieldParent = getFieldEditorParent();
this.pathField = new FileFieldEditor(PREF_KEY_2, "Path:", this.pathFieldParent);
addField(this.yesOrNoField);
addField(this.pathField);
boolean isChecked = getPreferenceStore().getBoolean(PREF_KEY_1);
updatePathFieldEnablement(! isChecked);
}
/**
* Updates the fields according to entered values
*/
private void updatePathFieldEnablement(boolean enabled) {
this.pathField.setEnabled(enabled, this.pathFieldParent);
}
@SuppressWarnings("boxing")
@Override
public void propertyChange(PropertyChangeEvent event) {
if (event.getProperty().equals(FieldEditor.VALUE) && event.getSource() == this.yesOrNoField) {
updatePathFieldEnablement(! (boolean) event.getNewValue());
}
super.propertyChange(event);
}
}
The propertyChange method is there to enable/disable the FileFieldEditor depending on the BooleanFieldEditor value.
It works OK if I change the BooleanFieldEditor valeu by checking or unchecking it, but the propertyChange is not called when I hit the "Restore default values" button.
Do someone see a reason for that?
OK, I think I've got my response.
I went further in my investigation and I got to this code which seems suspect to me:
In class BooleanFieldEditor :
@Override
protected void doLoadDefault() {
if (checkBox != null) {
boolean value = getPreferenceStore().getDefaultBoolean(getPreferenceName());
checkBox.setSelection(value);
wasSelected = value;
}
}
and in class StringFieldEditor
@Override
protected void doLoadDefault() {
if (textField != null) {
String value = getPreferenceStore().getDefaultString(
getPreferenceName());
textField.setText(value);
}
valueChanged();
}
We can see that the FileFieldEditor (that inherits from StringFieldEditor) launches an PropertyChangeEvent to its listeners (valueChanged();
) but not the BooleanFieldEditor. I did not find any code indicating that BooleanFieldEditor are using another mechanism. I think this is a bug in jFace.
To get around this problem, I just had to override the FieldEditorPreferencePage#performDefaults
method and the result's fine.