= Development =

[[PageOutline]]

== Structure ==
!ModRana consists of the main modrana.py "kernel", which handles the core functionality, like loading modules, managing the persistent options dictionary, providing platform-independent paths to essential modRana files and folders. It also handles modRana startup and shutdown.

Rest of the functionality is provided by "modules". All modules inherit the ranaModule base class. There are three types of modules:
 * '''device modules''' - provide platform/device adaptation
 * '''GUI modules''' - provide the GUI layer, are independent on the device modules
 * '''normal modules''' - provide various functionality independently on the platform and device modules (or more specifically should not depend on any specific GUI or device module)

Modules can be either file-modules (mod_foo.py) of folder-modules (mod_foo/mod_foo.py). Usually when a file-module grows to an unmaintainable size, it should be converted to a folder module and its functionality split to more files in its folder.
 
=== Modules ===

==== mod_location ====
Supports various location data providers and provides location data in a consistent format.

==== mod_online_services ====
Wraps various online services for use in modRana.

==== mod_messages ====
Handles messaging between modules.

===== Sending a message =====
All modules inherit the sendMessage(message) method from the base class.

===== Handling a message =====
If a module receives a message, its handleMessage(message, type, args) method is called

===== Message syntax =====
[prefix:]module_name:message[:optional_payload]
====== Plain messages ======
No prefix.

''Example:''

{{{
menu:reload
}}}
Is handled by the "menu" module (mod_menu.py).
message = "reload"[[br]]
type = None[[br]]
args = None

====== Message string ======
Has the '''ms''' prefix.

''Example:''

{{{
ms:route:reroute:fromStart
}}}
Is handled by the "reoute" module (mod_menu.py).
message = "reroute"[[br]]
type = "ms"[[br]]
args = "fromStart"

====== Message list ======
Has the '''ml''' prefix.
''Example:''

{{{
ml:storePOI:storePoint:12.3;45.6;Camelot
}}}
Is handled by the "storePOI" module (mod_menu.py).
message = "storePoint"[[br]]
type = "ml"[[br]]
args = ["12.3","45.6","Camelot"]
====== Message dict ======
Has the '''md''' prefix.

''Example:''

{{{
ml:storePOI:storePoint:lat=12.3;lon=45.6;name=Camelot
}}}
Is handled by the "storePOI" module (mod_menu.py).
message = "storePoint"[[br]]
type = "md"[[br]]
args = {"lat":"12.3","lon":"45.6","name":"Camelot"}

==== mod_menu ====
Menu structure representation and drawing. Currently mostly used by the GTK GUI.

==== mod_options ====
GTK GUI options menu structure.

==== mod_map_data ====
Batch tile download handling.

==== mod_log ====
Debug logging. Currently mostly concerned with redirecting stdout to a file, so that seldom ocuring errors can be easily loged.

==== mod_cron ====
Handles timers in a a graphics toolkit independent way. It currently supports GTK and Qt.

===== Adding a timer =====
addTimeout(self, callback, timeout, caller, description, args=[])
''callback'' - method that will be called by the timer[[br]]
''timeout'' - timeout in milliseconds[[br]]
''caller'' - instance of the calling module[[br]]
''description'' - a short string describing what the timer does[[br]]
''args'' - an optional list of arguments for the callback function[[br]]

The addTimeout method returns an id, that can be used to manipulate the the timer during its lifetime. If the callback method returns False (must be False, not "", 0, [] or similar), the timer is automatically canceled.


==== mod_ ====
==== mod_ ====
==== mod_ ====
==== mod_ ====


== Porting ==

[wiki:webos WebOS]

[wiki:android Android]

== Development notes ==

 [wiki:modranaIfrastructureImprovemetsEN modRana infrastructure improvements]

 [wiki:pyclutter_notes python-clutter notes]

 [wiki:pygame_touchpad running PyGame on the HP Touchpad]

 [wiki:voiceOutputLocalizationEN voice output localization]