Updating MIDlets on Series 40 phones (Known Issue)
The Nokia-Update JAD attribute should be used to update MIDlets.
Series 40 devices support a Nokia-specific JAD attribute called "Nokia-Update" which can be used to provide a URL for the update location of the MIDlet. When the URL in this attribute points to a JAR file, the update process (which the user can start from the Options menu) will create a new MIDlet instead of overwriting and updating the existing MIDlet.
The recommended solution is that the Nokia-Update attribute in the JAD file should not point to JAR URLs, but instead it should point to a JAD URL. For starters, all signed MIDlets need a new JAD (to get a new signature), and invariably a new JAD is needed (for new permissions, version number etc.) so it is bad practice to put a JAR URL in this attribute.
Note: If the Nokia-Update attribute in the JAD file is blank, the Update menu item in the Series 40 UI is disabled, which means that it is not possible to update the MIDlet.
Note 2: If this attribute does not exist in the JAD file and the MIDlet is downloaded OTA to the device, the system automatically adds this attribute for the MIDlet in question using the download URL.
How to reproduce
- Create a MIDlet with the update URL (attribute called Nokia-Update) in the JAD pointing directly to a JAR file.
- Install a MIDlet via PC Suite using both JAD and JAR files.
- Update the MIDlet
A new MIDlet will be created instead of the MIDlet being overwritten and updated.
Always use URLs to the JAD file in the Nokia-Update attribute.