The document discusses the GUI internals of qooxdoo, including its two-pass rendering process of measurement and arrangement. It describes how layout managers compute size hints and do rendering. The queueing system manages widget jobs, state changes, decorator updates, layout computation, DOM flushing, and disposer work. Events are centrally managed with custom dispatchers and support bubbling, capturing, and normalized mouse/keyboard input. Styles and attributes are normalized and synchronized to the DOM.

1. GUI Internals of
qooxdoo
Webinale 2008, Germany
Fabian Jakobs

2. Fabian Jakobs
• Software Developer at 1&1 Internet AG
Since 2007

3. Rendering Process
• Recursive Operation with Two Passes
• Measurement Pass
• Arrangement Pass

4. Size Hints
• Preferred Dimension of a Widget
• Developer can Override Them

5. Layout Managers
• Implement Basically Two Methods to:
• Compute the Size Hint
• Do the Actual Rendering

6. Queuing
• Widget Jobs
• State Changes
• Decorator Updates
• Layout Compution
• DOM Element Flush
• Disposer Work

7. Events
• Central Managment of Events
• Custom Dispatchers
• Bubbling and Capturing Phase
• Normalized Mouse and Keyboard Support
• Capable Focus Sub System

8. DOM Flush
• Normalization of Styles and Attributes
• Managed Synchronization to the DOM
• Connection to the Event System

9. Questions?