MIDP-OVM for Naked Objects Framework

Introduction

MIDP-OVM is an User Interface plugin which makes possible to run applications written for Naked Objects framework in a MIDP 2.0 capable mobile phone or other MIDP device. Existing Naked Objects applications can be run on a MIDP phone just by changing one line in a configuration file of the application.

In Naked Objects framework Object Viewing Mechanism (OVM) is independent of applications and applications are independent of OVMs. This makes possible to run Naked Objects applications with very different OVMs targeted to different devices or environments just by switching the OVM. And one OVM can be used with all Naked Objects applications. This way huge amounts of code can be saved when developing applications for multiple devices.

MIDP-OVM has reached 1.4 milestone with usability in the focus. MIDP-OVM is based on NO-framework version 1.2.2.

Screenshots & Videos

These screenshots are taken from Nokia 6630. Application below is an example application coming with Naked Objects framework - Orders. It has been extended a bit to test all the new features of MIDP-OVM.

Main menu of extended Orders application

A Video demonstrating Orders-application running on Nokia 6630 over 3G network from 400MHz linux server.

midp-ovm-1.4.mpeg (mpeg1, 320x240, 5 mins, 11.6 MB)

Version history

27.2.2005 version 1.4

Contains new features mainly concentrated on usability improvements. Created by Hanna Sirviö, Aki Heikkinen, Aki Pöyry and Juha Häikiö in another student project for VTT Technical Research Centre of Finland, Oulu.
Associations can now also be created and replaced using a list of all instances assignable to the class of the association instead of the clipboard. Such a list (a Choice View) will be brought up whenever no applicable instance is found on the clipboard, and if there is one on the clipboard, the user is allowed to decide whether to use the list or the object on the clipboard. About-directives are respected and unsuitable choices presented prefixed with an asterisk.
If the user attempts to create an association vetoed by an About-directive, an error message with the description provided in the About is shown.
A special way to create instances of association classes was implemented, f. ex. an item may now be added to an order by providing a product. The user may add associations to particular fields using objects of arbitrary classes defined by the application programmer. A InternalCollection subclass named IntermediaryCollection handling these mappings is provided. The intermediary collection can also be directly used with any other OVM to provide the same functionality. See section "Customising the MIDP-OVM" in readme.txt for more information.
The Naked Object View is now more compact and hopefully more consistent between different devices.
The separate Create Naked Object View and Edit Naked Object View were replaced with a possibility to edit value fields of naked objects directly in the Naked Object View. Changes are auto-saved when the user navigates outside the view.
Renderers for Naked Objects Framework Date and Time using the MIDP editors for such values are provided.
Progress indicators have been improved significantly. They convey more information of what activity is going on between the Client and the Server, and are also now used consistently throughout the application.
When a naked object is put to the clipboard, a pop-up message showing what was put on the clipboard is presented to the user.
The delete object -command was moved from Naked Object View to Class View.
Bug fix: invoking the select action (e.g. pushing the Nokia 6630 joystick inwards) on an instance in a Class View no longer puts the instance on the clipboard but opens a Naked Object View of it instead.
Bug fix: immediately issuing commands without moving the cursor to an item other than the first one in the view after entering a Naked Object View no longer has unpredictable results.

31.1.2005 version 1.0

Created by Maria Siniaalto, Andreas Brodt, Vili Törmänen and Jussi Liikka in a student project for VTT Technical Research Centre of Finland.
complete rewrite of the 0.1.1 version
now works in a real MIDP 2.0 phone (Nokia 6600 and 6630 models tested)
can now create and edit objects
can associate and dissociate objects by using clipboard as a replacement for drag-and-drop
can invoke zero and one parameter methods
supports creating application specific custom views for objects

22.9.2004 version 0.1.1

The MIDP-OVM was actualized in co-operation of VTT Technical Research Centre of Finland and the Department of Electrical and Information Engineering of the University of Oulu. The project was carried out by a group of three Information Engineering students, Teemu Tokoka, Outi Kenttä and Maria Siniaalto as the project assignment for the Advance Software Engineering Project during the summer 2004. The first version was able to browse Naked Objects, but not edit them.

Downloads

Version 1.4 - public version is available only via GPL license, other licenses can be negotiated.

midpovm-1.4.zip

Version 1.0 - public version is available only via GPL license, other licenses can be negotiated.

midpovm-1.0.zip

Version 0.1.1 - published on a dual licencing basis, GPL and FreeBSD licenses.

midpovm-0.1.1-package.zip - Includes APIs, source and binaries.

midpovm-0.1.1-src.zip - The source.

Contact information

Heikki Keränen (heikki dot keranen at vtt dot fi)

Links

Page updated 27.2.2006