Base message handling for real time data plot communications. More...
#include <rtmessage.h>
Public Member Functions | |
| virtual | ~RTMessage () |
| Virtual destructor. | |
| virtual void | setMessage (QByteArray &buffer)=0 |
| Called to fill out the send buffer with the contained message. More... | |
| virtual int | readMessage (const QByteArray &buffer)=0 |
| Called to read incoming data from the given buffer. More... | |
| virtual QStringList | headings () const =0 |
| Request the list of headings for the plot. More... | |
| virtual unsigned | populateValues (std::vector< double > &values) const =0 |
| Request the latest values. More... | |
Detailed Description
Base message handling for real time data plot communications.
Implementations support reading and writing messages for real-time plot communications. There are two key implementations; RTStringMessage and RTBinaryMessage.
For sending, only setMessage() is called. For reading, the sequence is:
readMessage()to populate this instance with data from the message buffer.populateValues()to get the latest values.headings()to determine the headings
The headings() stops once a valid set of headings is returned. This is to support string based messaging where the number of headings is not given in advance, but stops requesting headings once known.
Member Function Documentation
|
pure virtual |
Request the list of headings for the plot.
- Returns
- The headings or an empty list if not yet known.
Implemented in RTBinaryMessage, and RTStringMessage.
|
pure virtual |
Request the latest values.
Uses a std::vector, not QVector because the former can be cleared without reallocation (at the time of writing).
- Parameters
-
values Resized and populated to the latest values set.
- Returns
- The number of values available.
Implemented in RTBinaryMessage, and RTStringMessage.
|
pure virtual |
Called to read incoming data from the given buffer.
- Parameters
-
buffer The buffer to read from.
- Returns
- The number of bytes read on success, negative on error. Zero if nothing to read.
Implemented in RTBinaryMessage, and RTStringMessage.
|
pure virtual |
Called to fill out the send buffer with the contained message.
- Parameters
-
buffer The buffer to write to.
Implemented in RTBinaryMessage, and RTStringMessage.
The documentation for this class was generated from the following file:
