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The Java Developers Almanac 1.4Order this book from Amazon. |
e421. Listening for Changes to Preference Values in a Preference NodeAPreferenceChangeEvent is fired when a preference is added,
changed, or removed from a preference node. This event is only
guaranteed to fire if the listener and modifier are in the same
application. This event is not fired if the node is removed.
See also e422 Determining When a Preference Node Is Added or Removed. // Retrieve the user preference node for the package java.lang Preferences prefs = Preferences.userNodeForPackage(String.class); // Register the listener prefs.addPreferenceChangeListener(new PreferenceChangeListener() { public void preferenceChange(PreferenceChangeEvent evt) { // Get the node that changed Preferences node = evt.getNode(); // Get the affected key. // Note: it is not possible to tell if the key was new // or its value was changed. String key = evt.getKey(); // Get the new value; if the new value is null, // the preference was removed String newValue = evt.getNewValue(); } }); // Add a preference prefs.put("key", "a string"); // Modify the preference prefs.put("key", "a new string"); // Remove the preference prefs.remove("key");
© 2002 Addison-Wesley. |