Some details about the initialization of a qooxdoo application.

1. Load HTML
2. Load the JavaScript files

1. Merge user settings from previously defined qx.Settings.
2. Load qooxdoo core (OO, Array, String, validation, Object, ...)
3. Load Logging module
4. Instantiate qx.Init
   1. attach event handler to onload, onbeforeunload and ununload

    qx.core.Init.getInstance().setApplication(my.namespace.Application);

qx.Init._onload:

1. looks up the default application component from the settings. The default is qx.component.init.InterfaceInitComponent.
2. delegates initialization of the framework to the application component

InterfaceInitComponent starts the three loading phases:

1. initialize
2. main
3. finalize

1. Instantiate qx.ui.core.ClientDocument. ClientDocument is the basic widget of all qooxdoo applications. It is the parent of all children inside your application. It also handles their resizing and focus navigation.
2. Instantiate qx.event.handler.EventHandler. The event handler themselves get not yet attached.
3. Call initialize of the user defined applications class

1. Call main of the user defined applications class.
2. Start preloading of images

This phase is started after the image preloader system has finished loading.

1. Flush global queues. This creates the DOM nodes of the widgets and applies styling.
2. Global event handler for mouse, key and focus events are registered.

1. Call finalize of the user defined applications class.

1. Load HTML
2. Load qooxdoo.js file
   1. Merge user settings from previously defined QxSettings.
   2. Load the debug console
   3. Create an application instance
3. Application Initialization (will be started on the “load” event of the window)

1. Print version and build information
2. Output available classes
3. Output client informations
4. Application starts objects “pre” method (which can be defined through the qooxdoo application developer)
5. Application fires “pre” event
6. Create an instance of QxClientWindow
   1. Registering unload event to dispose application before leaving the document.
   2. Create an instance of QxClientDocument and assigning “document” element
      1. Create an instance of QxFocusManager to handle the focus handling inside the client document, which behaves like a typical focus root.
   3. Create an instance of QxEventManager and assign events to this instance.
7. Remapping methods from QxParent to QxApplication so that the application behaves like the client document in some aspects (add or remove children, ...)

1. Application starts objects “main” method (which can be defined through the qooxdoo application developer)
2. Application fires “main” event

1. Wait for initially visible images to load

1. Application starts QxWidget queue flush
   1. Create DOM elements and assign styles, attributes and events
   2. Layout children using layout implementation of each parent
   3. Flush of display queue. Add created DOM elements to the tree in a heavily optimized way.

1. Application initializes “post” handling
   1. Application starts objects “post” method (which can be defined through the qooxdoo application developer)
   2. Application fires “post” event

1. Loading of initially invisible images