Add a custom MIME type for all users

Petr Kovar pknbe@volny.cz Add a custom MIME type for all users

To add a custom MIME type for all users on the system and register a default application for that MIME type, you need to create a new MIME type specification file in the /usr/share/mime/packages/ directory and a .desktop file in the /usr/share/applications/ directory.

Add a custom <sys>application/x-newtype</sys> MIME Type for All Users

Create the /usr/share/mime/packages/application-x-newtype.xml file:



  
    new mime type
    
  
]]>

The sample application-x-newtype.xml file above defines a new MIME type application/x-newtype and assigns file names with the .xyz extension to that MIME type.

Create a new .desktop file named, for example, myapplication1.desktop, and place it in the /usr/share/applications/ directory:

[Desktop Entry]
Type=Application
MimeType=application/x-newtype
Name=My Application 1
Exec=myapplication1

The sample myapplication1.desktop file above associates the application/x-newtype MIME type with an application named My Application 1, which is run by a command myapplication1.

As root, update the MIME database for your changes to take effect:

# update-mime-database /usr/share/mime

As root, update the application database:

# update-desktop-database /usr/share/applications

To verify that you have successfully associated *.xyz files with the application/x-newtype MIME type, first create an empty file, for example test.xyz:

$ touch test.xyz

Then run the gio info command:

$ gio info test.xyz | grep "standard::content-type" standard::content-type: application/x-newtype

To verify that myapplication1.desktop has been correctly set as the default registered application for the application/x-newtype MIME type, run the gio mime command:

$ gio mime application/x-newtype Default application for “application/x-newtype”: myapplication1.desktop Registered applications: myapplication1.desktop Recommended applications: myapplication1.desktop