The calling sequence for ALooperRoster::deliverMessage

1. ALooper::start()
  while runOnCallingThread is true
  call ALooper::loop()

2. ALooper::loop()
   call gLooperRoster.deliverMessage(event.mMessage);
   
   gLooperRoster is defined in ALooper.cpp as a global variable of ALooperRoster.
   
3. ALooperRoster::deliverMessage
   By calling handler->onMessageReceived(msg) to call the substruct's realization for onMessageReceived method
   eg: The onMessageReceived method of MyHandler struct

4. substruct of struct AHandler
(1)AHandlerReflector.h (frameworks\base\include\media\stagefright\foundation):struct AHandlerReflector : public AHandler {
(2)AHierarchicalStateMachine.h (frameworks\base\include\media\stagefright\foundation):struct AHierarchicalStateMachine : public AHandler {
(3)ARTPConnection.h (frameworks\base\media\libstagefright\rtsp):struct ARTPConnection : public AHandler {
(4)ARTPSession.h (frameworks\base\media\libstagefright\rtsp):struct ARTPSession : public AHandler {
(5)ARTSPConnection.h (frameworks\base\media\libstagefright\rtsp):struct ARTSPConnection : public AHandler {
(6)LiveSession.h (frameworks\base\media\libstagefright\include):struct LiveSession : public AHandler {
(7)MPEG2TSWriter.cpp (frameworks\base\media\libstagefright):struct MPEG2TSWriter::SourceInfo : public AHandler {
(8)MyHandler.h (frameworks\base\media\libstagefright\rtsp):struct MyHandler : public AHandler {
(9)MyTransmitter.h (frameworks\base\media\libstagefright\rtsp):struct MyTransmitter : public AHandler {
(10)NuPlayer.h (frameworks\base\media\libmediaplayerservice\nuplayer):struct NuPlayer : public AHandler {
(11)NuPlayerDecoder.h (frameworks\base\media\libmediaplayerservice\nuplayer):struct NuPlayer::Decoder : public AHandler {
(12)NuPlayerRenderer.h (frameworks\base\media\libmediaplayerservice\nuplayer):struct NuPlayer::Renderer : public AHandler {
(13)Sf2.cpp (frameworks\base\cmds\stagefright):struct Controller : public AHandler {
(14)UDPPusher.h (frameworks\base\media\libstagefright\rtsp):struct UDPPusher : public AHandler {