1fpdfsdk/pwl is a Widget Library for AcroForms. 2 3CPWL_Wnd is the base class that widget classes extend. The derived widget 4classes are controllers for each widget. The hierarchy is: 5 6* CPWL_Wnd 7 * CPWL_Button 8 * CPWL_CheckBox 9 * CPWL_PushButton 10 * CPWL_RadioButton 11 * CPWL_Caret 12 * CPWL_EditCtrl 13 * CPWL_Edit 14 * CPWL_ListBox 15 * CPWL_CBListBox (combo box) 16 * CPWL_ScrollBar 17 18Widgets are rendered to Appearance Streams, with the case all centralized in 19CPDFSDK_AppStream. 20 21