Desktop file format
Contents |
Maemo 5 - Fremantle
application.desktop files are read from directory:
/usr/share/applications/hildon/
application.desktop files consist of at least one Desktop Entry group, containing at least the fields Type and Name.
Maemo application.desktop files conform with the freedesktop.org desktop entry spec version 1.0.
These files are parsed by a number of different modules in Maemo: hildon-desktop reads them to display icons in the main application menu, and launch applications. libhildonmime reads the files to launch applications associated with a specific mime type.
Standard keys
Maemo recognises and parses a subset of all of the standard keys defined in the desktop spec. The following keys have a specific meaning in Maemo:
| Key | Type | Meaning | Required? |
|---|---|---|---|
| Type | string | Possible values are "Application", "Link" or "Directory". Only "Application" and "Directory" are parsed on Maemo. | Y |
| Name | string | The name of the Desktop Entry group - should be unique on the system | Y |
| Icon | string | Icon to display in file manager, menus, etc. If the name is an absolute path, the given file will be used. If the name is not an absolute path, the algorithm described in the Icon Theme Specification will be used to locate the icon. | N |
| Comment | string | Tooltip for the icon. Unused in touch interface. | N |
| NoDisplay | boolean | If this is set to true the icon will not be shown in the menu. This is useful for applications which are associated with a mime type, but are not intended for standalone use.
| N |
| Exec | string | The absolute path to the executable to be run when the desktop entry is selected. | N |
| Categories | string | This field is not used by hildon-desktop, but is used by 3rd party applications such as Catorise | N |
| MimeType | string | Parsed by libhildonmime, this field relates the mime type of a file to the applications which can be used to open it. | N |
Maemo extension keys
The following keys have a particular meaning on Maemo. None of these fields are required.
| Key | Type | Meaning |
|---|---|---|
| X-Text-Domain | string | The L10n domain from which the application name is translated (with dgettext) |
| X-Osso-Service | string | DBus service name - if specified hildon desktop will try to call the top_application method on this service rather than execute what is listed in the Exec field). |
| X-App-Loading-Image | ||
| X-Maemo-Prestarted | boolean | If true, the application will be started automatically at boot time |
| X-Maemo-Wm-Class | ||
| X-Maemo-Prestarted-Priority | nuber | Proprity for the application launch - lower means application is launched sooner |
| X-Maemo-Switcher-Icon | ||
| X-Maemo-Ignore-Lowmem | boolean | Ignore the low memory status when this application is launched. If this is absent, or set to false, an application will not be launched if there is insufficient memory available. |
| X-Maemo-Prestarted-Ignore-Load | boolean | If true, prestart the app as soon as possible without regards to load or memory limits |
| X-Osso-Service | string | The name of the DBus service to call to start this application on demand |
| X-Osso-URI-Actions | string | Used in version 1 of URL handler to indicate URI handlers which this application can deal with |
Note that while Maemo 5 (Fremantle) does not by default read the "Categories="-entry from the desktop file, enhanced menu applications like Catorise do. It is recommended that you add a Categories line to the .desktop file.
Categories=Office; Office or whatever Category is suitable
It is silently ignored in the standard application menu, but allows you to pre-define the location of your application in Catorise. A list of valid categories is found here.
The canonical source for the key types supported on Maemo for the application menu is the hildon-desktop module, and specifically the files src/launcher/hd-launcher-item.c and src/launcher/hd-launcher-app.c
URL handlers
There are a number of custom fields used in hildon-uri.c to handle custom URI groups.
OS 2008 - Chinook
Format of Maemo .desktop files
Below are the fields supported in hildon-desktop:
- Type
- Should be application
- Icon
- Name
- Categories
- not used on Maemo, but used in Ubuntu mobile
- Comment
- now unused, was used as second line of text in the startup menu in Bora
- Exec
- NoDisplay
- set to true to hide the entry in the menu
- StartupNotify
- set to false to disable the startup notification banner
- StartupWMClass
- used to override the expected window class name, default to the binary name
Some Maemo-specific extensions:
- X-Text-Domain
- set the L10n domain from which the application name is translated (with dgettext)
- X-Osso-Service
- a DBus service name - if specified hildon desktop will try to call the
top_applicationmethod on this service rather than execute what is listed in the Exec field).
(Credits to Johan Billen)
BTW: If your application needs the browser to do special URL handling, the desktop file needs to be extended accordingly.