Give

Statusbar plugin for easy drag & drop data sending via Bluetooth.

Version:

0.8.0

Author:

Dénes Mátételki <denes.matetelki@gmail.com>

Date:

2008

Plot summary

After analizing the data exchange services of the current devices used in mobile communication, came the idea of an application, which uses the possibilities of Bluetooth. Due to the survey, most of the mobile devices has Bluetooth capabilities, but no WLAN or 3G.

The idea is to accomplish the following use-cases: Two people meet with devices of Bluetooth capabilities so WLAN or internet is not needed, since at most places, for example at a railway station, free wlan connection is not always present, and most of the devices don't have 3G adapters. At the device of the data exchange initiative person, the application is running, however it is not necessary for the data receiver's device, to have the application installed.

The target device is the N800 series of Nokia, which is a linux-based internet tablet and has Bluetooth and WLAN adapters. The data exchange initiative person owns a device of this kind, with the application, Give.

The project focuses on two services:

• Sending data, providing compatibility with as much application as possible, by using standards. Applications provided by the vendor have high priority.
• Sharing internet access to devices which has Bluetooth adapter but no 3G or WLAN capabilities.

The data exchange in this case is not a server-client or a sharing type, the data provider initiates the transaction, "gives" the information to the destination.

The name comes from here, Give.

The icon shows a hand, offering, "giving" an apple.

Services

• Sending text OK
• Sending file(s) OK
• Sending calendar event OK with dates, compiled with --enable-dnd=yes
• Sending business card OK
• E-mail sending TODO patch modest to produce complete e-mail at drag & drop
• Sharing internet access. TODO The device doesn't act as a server, just client.

The application has been accomplished as a statusbar-plugin, represented by an icon in the top-rigth status line, which can always be seen. The choice come down to this because an icon, visible all the time, always available for a drag & drop destination.

So for the sake of the fastest data sending, data objects are selected with drag & drop, by dropping the data object to the application icon, to by-pass the time spent in context-sensitive menus.

Objects

The project separeted into four projects.

• The project itself is a hildon-statusbar-plugin, which means it is an icon, in the statusbar area which interacts with user actions and shows the some state of system. The icon is a GTK+ drag & drop destination, and the actions to be taken upon a data drop is described in the drag & drop object.
• The drag & drop object examines the recieved data, converts it into file or files, according to its nature. For example, a contact will be send as a VCard, a calendar event as an VCal event, and so on. For VCard data manipulation, an EBook connection has been defined. The data transfer has been done with the Bluetooth object. Also, the state of the device's Bluetooth is checked, and if it's turned off, a dialog appears, asking for permission of the user to turn it on.
• The EBook interacts with the Evolution Data Server's EBook component, for data queries, and VCard representations of the contacts.
• The Bluetooth object is responsible for the data transfer. It uses a convenient D-Bus call, which invokes the Hildon Connectivity's Bluetooth rutines. They pops up a dialog to select a visible Bluetooth device as the destination of the sending, doing the data transfer and handling the success or failure cases.

Object relations

The objects are not derived from each other, they are encapsulated.

The _GiveStatusbarPlugin derives from StatusbarItem which derives directly from GObject, like _give_drag_and_drop, _give_bluetooth and _give_ebook.

The encapsulation is like the following:

give_statusbar_plugin
   +----give_drag_and_drop
            +----give_bluetooth
            +----give_ebook

Installation

./autogen.sh
./configure --enable-ltc=yes --enable-ltf=yes
make
make install

The two configure options are: enable log to console and enable log to file.

Keywords

Nokia Internet Tablet, maemo, Bluetooth, drag & drop, IP over Bluetooth, PAN.

Screenshot

A screenshot of the menu of Give

Todos left

• Patch modest.
• Solve the pand error.
• Look for memory leaks.

Known bugs

• Selecting Control Panel -> Panels -> Statusbar -> selecting Give's checkbox off, then close Panels menu. Open again and the desktop craches. Object registration issue?

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