Top-Level DesignFragment, Activity, and Scalable DesignVisual Editing of User InterfacesStarting with a Blank SlateLaying Out the FragmentsLay Out Fragments Using the Visual EditorMultiple LayoutsFolding and Unfolding a Scalable UIDecisions about Screen Size and ResolutionDelegating to Fragment ClassesMaking Activity, Fragment, Action Bar, and Multiple Layouts Work TogetherAction BarTabs and FragmentsThe Other Activity