Revision as of 06:09, 7 July 2011

This page is intended to serve as an ongoing development guide in relation to using QML as the engine for LinuxMCE's user interface. We shall outline relevant documents relating to QML as well as specifics for designing a skin. Please note, if you are reading this, then this is in fact an ongoing guide and as such information is apt to change. Personal notes are to be kept in the discussion area of this page, please post only code, links, or other relevant data to UI development. This message will self-destruct in 10 seconds.

QML KnowledgeBase

An Overview of what QML is http://labs.qt.nokia.com/2009/05/13/qt-declarative-ui/ A document on styling and whats important, skinning - http://developer.qt.nokia.com/wiki/QmlStyling

• http://developer.qt.nokia.com/wiki/JavaScript_programmer
• http://doc.qt.nokia.com/4.7-snapshot/qdeclarativeintroduction.html
• http://doc.qt.nokia.com/4.7-snapshot/qdeclarativeelements.html

Stay tuned to this development space

Downloads & Initial setup

• http://qt.nokia.com/downloads The SDK you will need. Previous releases will NOT work

Setting it up

I installed qt creator into home, although the default location is opt. Installing it into home will allow you get up and running right away but if installed into opt you will need to export some paths as described below.

via irc and TSCHAKeee

i literally just copy -ax /opt/QtSDK/Desktop/* to the core
either tarballing it up or otherwise
then export PATH=/opt/QtSDK/Desktop/Qt/473/gcc/bin:$PATH
then export LD_LIBRARY_PATH=/opt/QtSDK/Desktop/Qt/473/gcc/lib:$PATH
this can be placed in your .bash_profile
and you can then run qOrbiter

You should then be able to compile / run / hack on qOrbiter

Initial Findings

All research is being done against the current branch of code in the svn. The Big Idea(tm) is do the following: Create a new orbiter using qml as our ui both for its portability and skinning ease of use.

Initial experiments http://wiki.linuxmce.org/index.php/Qml http://forum.linuxmce.org/index.php?topic=11722.0

If you are interested in playing with skinning only you can find the skinning document QOrbiter Development Page.

UI

• Determine to what level we want QML to control the UI vs the c++ code.
• Provide a set of constant objects for UI designers to connect to for data
• Provide basic qml elements for some design objects. Think buttons specifically. These would be referred to as custom qml 'components'
• Develop a base template for styles to follow. This would allow changes to be made globally that would affect all qml objects loaded.
• determine animations sets for our custom qml objects

Following this idea further, its been decided to attempt to define the orbiter varables and data as a complex Data model. While the disadvantage is the complexity of the model, it will expose essentially a simple api to skin designers to access linuxMCE data in their skin, further removing programmatic responsibilities from the ui.

The initial work in this area includes

• creating the needed subclassed models from QAbstractListModel
• creating a purpose specific orbiter generator as the current orbiter gen does more than is needed and is too tightly coupled to the concept of deign_obj's something we wish to get away from.

C++

There will need be be considerable time invested into understanding and picking apart certain functions of the existing orbiter to determine relevance in any new orbiter. These include not just the orbiter itself, but datagrids and how it interacts with other plugins. We will need to translate the functionality to new methods because of the inherent difference in the two ui toolkits. Things such as screen handlers and the callback system will be replaced with the signal and slots mechanisms of Qt and so must be understood to be replaced.

• Datagrids - Custom DataModel has been implemented.
• Screen Handlers - Handled by native qt functions
• Mouse Handlers - Not needed as of yet