View source for Plasma/shellPackage

There will be two shell packages (with the same PackageStructure)  loaded on the shell: a "global" one that will provide fallback files, while another package will be loaded specific of the device form factor. Files will be searched for in the formfactor package, then if not found will be searched for in the "global" package.

=Package filesystem=
Package Type in desktop file: Plasma/Shell

 contents/components/
 contents/views/
 contents/layout.js -> file
 contents/defaults ->file

==contents/components/==
Shell UI components - named files
	AppletError.qml
	CompactApplet.qml
	Configuration.qml
	WidgetExplorer.qml

''TODO'': this folder goes away, every named file gets its own directory

==contents/views/==
Each view (panel view or desktop view) will load a qml file that will "contain the containment", it will have the form
	<containment type>.qml
Where <containment type> is allowed to be '''Desktop''' or '''Panel'''

==contents/layout.js==
The default layout JavaScript file supports a similar API to Plasma1 desktop scripting.
The manipulation of Applet geometry will change a bit, see [[#Applet_geometry_manipulation_from_scripts|Applet geometry manipulation from scripts]]

==contents/defaults==

Default settings
	ContainmentActions
	Default containment for each type
	Default toolbox

Example defaults config file

 [Desktop]
 Containment=org.kde.desktop
 ToolBox=org.kde.standardtoolbox
 [Desktop][ContainmentActions]
 Ctrl;LeftButton=org.kde.standardmenu
 MiddleButton=org.kde.paste
  
 [Panel]
 Containment=org.kde.panel
 ToolBox=org.kde.standardtoolbox
 [Panel][ContainmentActions]
 Ctrl;LeftButton=org.kde.standardmenu
 
 [Theme]
 Theme=air-mobile

Layout package details
In metadata.desktop:
X-Plasma-ContainmentCategories=<containment type>

Applet geometry setting
Containment geometry strategies:
	* None
	* Indexed
	* Grid
	* Free
	* Grouped

=Applet geometry manipulation from scripts=
==QML part==
 Item {
     property int appletPlacementStrategy: “indexed”
  
     Connections {
   	    target: parent
            onIndexedPlacementRequest: {
                parameters: applet, index
            }
            onGridPlacementRequest: {
                parameters: applet, x, y
            }
            onFreePlacementRequest: {
                parameters: applet, point
            }
     }
    [...]
 }

==C++ part in ScriptEngine==
 PlacementStrategy ContainmentInterface::placementStrategy() const
 {
      // look up the appletPlacementStrategy property and return it
 }
 [...]
 void ContainmentInterface::requestIndexedPlacement(Applet *applet, int index)
 {
        if (placementStrategy() == IndexedStrategy) {
            emit indexedPlacementRequest(applet, index);
        }
 }