qooxdoo is on par with the desktop GUI toolkits such as QT, Java Swing, and so on. It provides a whole lot of off-the-shelf widgets for the GUI development. The good thing with the qooxdoo framework is the demo browser application, where you can see the behavior of each widget even without setting up the qooxdoo environment.
Similar to the feed reader application, demo browser is another application that comes with the qooxdoo framework. You can use this application to see the behavior of different widgets and select the widget that you want to use in your application. This application demonstrates various widgets, and it displays the widgets under neat categorizations such as widget, layout, UI, and so on.
In addition to the demo browser application, the qooxdoo framework provides another application called playground. As the playground application is linked with the demo browser, you can select the widget that you want to use in the demo browser, take that widget to the playground, change the code, run it, and see the behavior.
This makes it easy to select the widget in the demo browser; try it in the playground before actually trying it in your application. You can access the online version of these applications for the current qooxdoo version. You can also set these applications locally in your network if you download the qooxdoo framework. We will explore the online version of these applications in this section.