This inheritance list is sorted roughly, but not completely, alphabetically:

[detail level 12]

CApplication	Main class of the app
CDBPlaylist::BasedOn
CClient	abstract class for FSClient, YandexClient, AppClient. Designed to work with File dervied clases. Do all the real job getting data.
CAppClient
CFSClient
CYandexClient
CContext
CDatabaseManager	The DatabaseManager class
CDBPlaylist	DataBasePlaylist - playlist representation in database
CDBTrack	The DataBaseTrack - track representation in Database
CDebug	Draw messages with ncurses or print them in debug file
CDialogBundle	DialogElement Bundle; Abstract class. Create and switches a sequence of DialogElements
CNewElementsDialogBundle	sequence of DialogElements that aims to add new tracks(metadata) to application's data.
CDialogElement	Abstract class. Visual element designed to process some user input in a dialog format
CConfirmDialogElement	Used to Confirm some information. Usually the only data/input that changes is mHorizontalChoice
CLineEditDialogElement	Has line that user able to edit. Goal of this Dialog is simply get some text line data from user
CListDialogElement< ElementPtr >	The ListDialogElement class
CElementSelector< ElementPtr >	The ElementSelector class - class to select & draw list of elements
CElementSelectorState	The ElementSelectorState - struct to store element selector state
CEvent
CFile	Abstract class for FsFile, YaFile and AppFile
CAppFile
CFsFile
CYaFile
CHorizontalOptionChoice	part of the DialogElement. Most or all of the dialogs has this horizontal option choice at the bottom of the window
CHotKeyComponent	class to handle pre defined bindings
CConfirmDialogElement::LocalBounds	Bounds for some of the class visual objects
CLineEditDialogElement::LocalBounds	Bounds for some of the class visual objects
CListDialogElement< ElementPtr >::LocalBounds
CMainWindow	The MainWindow class
CMusicPlayer	class to play music, change music volume, fastforward/rewind, etc
CPlaylistDao	Database class to manipulate playlist related data
CProgressBar
CRect< T >
CSubWindow	The SubWindow class
CAppFilesSW	AppFilesSW = Application Files Subwindow
CDialogSW	operates with Dialog Bundles
CLocalFilesSW	The LocalFilesSW class; Local Files SubWindow is responsible for navigating in local filesystem, open folders, selecting tracks, etc
CPlayerSW	The PlayerSW class; Player SubWindow class is responsible for selecting tracks to play now
CPlayerStatusSW	The PlayerStatusSW class; Player Status SubWindow responsible for current track information, like track progress, track name, etc
CYandexFilesSW	The YandexFilesSW class; Yandex Files SubWindow is responsible for navigating in yandex music "filesystem"
CSWEvent	SubWindow Event
CSWHolder	Does not own SubWindows It's only responsible for Positions, Size, Resize events and what SubWindow to display
CSWManager	SubWindowManager is a SubWindow's and SWHolder's manager
CTime
CTrackDao	Database class to manipulate tracks related data
CVector2< T >
CXmlParser	A convenient class to parse xml keybindings. Uses opensource rapidxml libarary (xml lib is probably from there https://github.com/Fe-Bell/RapidXML)