Defining commands in plugins

A plugin can register custom commands by using the following code in the plugin:

def register_commands():
    @command.command("What is your name?")
    def ask_the_name(name):
        print name

    from qgiscommand import command
except ImportError:

The ImportError check is there so no error is raised to the user when the Command Bar plugin is not installed. If the Command Bar plugin is installed the command module will be imported and the register_commands function is called. You can register your custom command by following the API guide.