Inherits QMap< QString, QDBusVariant >.
Mapping type generated from the specification. Convertible with QMap<QString, QDBusVariant>, but needed to have a discrete type in the Qt type system.
 
Mapping representing a class of channels that can be requested
  from a connection manager, can be handled by a user interface,
  are supported by a contact, etc.
Classes of channel are identified by the fixed values of
  a subset of their properties.
Channel classes SHOULD always include the keys
    ChannelInterface::ChannelType   
  and
    ChannelInterface::TargetHandleType   .
  (One exception is that   ChannelTypeContactSearchInterface channels do not have TargetHandleType
  None in their requestable channel classes, for
  historical reasons.)