One letter string into char and then bit-wise comparing

roboterprogrammer

Hello,

first thanks to the community to have helped me with qtcpserver, qtcpclient and sockets ....

now what i want do:
from the robot i send strings via tcpip to my qt-gui-program, and in some of those strings i have one statusbyte at the end:
qstring statusbyte = line.right(1)

in this byte, 6 bits tells me about robots status, so what i want to do after i got this byte, is to check it bitwise with the if-operator, and then i want to make signals to the gui, so the woman (in or company a lot of woman work at the machines... ) can see in gui about robots status.

how do i convert the one sign qstring in a byte and then how do i check its bits in qt-style?

thanks a lot and nice weekend

tucnak

Hi. You can send QByteArray insted of QString.
@
QByteArray data = QString("data that you want to transfer").toAscii();
QByteArray statusbyte = line.right(1);
QByteArray pack = data+statusbyte;

// and now to convert

QBitArray = pack.right(1);
QString data = pack.left( pack.size()-1 ); // without statusbyte

@

shanek

You can use at() or constData() to get array elements from a QString or QByteArray.

e.g.
QByteArray data("test stringX");
char status = data.at(data.length() - 1);
// status == 'X'

You can use QFlags or just the C++ integer & operator to test bits in the status byte.

roboterprogrammer

hi,

thanks for the advices,
now i have one char or qbytearray of dimension 1.

how do i check now if bit 3 is 0 or 1?
i would like to get a bool with testflag but it doesnt work fore me yet.
i dont unterstand exactly how to do it with qflags,
can s.o. give me an advice?
Q_DECLARE_OPERATORS_FOR_FLAGS(?)

thanks

andre

Did you actually create a QFlags type with the relevant enum?
Something like:

@
enum RobotStatusFlag {
StatusOne = 0x1,
StatusTwo = 0x2,
StatusThree = 0x4,
StatusFoo = 0x8,
StatusBar = 0x10
}
Q_DECLARE_FLAGS(RobotStatusFlag, RobotStatusFlags);

Q_DECLARE_OPERTORS_FOR_FLAGS(RobotStatusFlags);
@

That would allow you to do something like:
@
RobotStatusFlags status(data.at(data.length() -1);
if (status.testFlag(StatusFoo)) {
// do something foo-like
}
@

roboterprogrammer

thanks, that helped a lot!