QFlags questions

[elcuco]

This is my fist time using QFlags and something is not working here. I am probably missing something very stupid and I need a second eye...

4428

Edit:
code is simple enough to put inline as well...


#include <QCoreApplication>
#include <QFlags>
#include <QDebug>

class foobar{
public:
enum MyFlag{
flag1, flag2, flag3
};
Q_DECLARE_FLAGS(MyFlags, MyFlag)

MyFlags m_state;

void setFlag( MyFlag f, bool enable){
if (enable)
m_state &= !f;
else
m_state |= f;
}

void toggleFlag( MyFlag f ){
setFlag( f, !m_state.testFlag(f) );
}

bool getFlag( MyFlag f){
return m_state.testFlag(f);
}
};

int main()
{
foobar f;
qDebug() << "Flags state" << f.getFlag( foobar::flag1 );
f.toggleFlag(foobar::flag1);
qDebug() << "Flags state" << f.getFlag( foobar::flag1 );
}

[wysota]

I think the enum should have proper values (i.e. powers of 2 - 1, 2, 4, 8, etc.) so that flags don't interfere with each other. You might also want Q_DECLARE_OPERATORS_FOR_FLAGS if something doesn't compile.

[elcuco]

'Ok, new version. Now I get the correct value (false) by default. This was done by the new default values of flags. still, after "toggle", I don't see the flags changing state:


#include <QCoreApplication>
#include <QFlags>
#include <QDebug>

class foobar{
public:
enum MyFlag{
flag1 = 1,
flag2 = 2,
flag3 = 4
};
Q_DECLARE_FLAGS(MyFlags, MyFlag)

MyFlags m_state;

void setFlag( MyFlag f, bool enable){
if (enable)
m_state &= !f;
else
m_state |= f;
}

void toggleFlag( MyFlag f ){
setFlag( f, !m_state.testFlag(f) );
}

bool getFlag( MyFlag f){
return m_state.testFlag(f);
}
};
Q_DECLARE_OPERATORS_FOR_FLAGS(foobar::MyFlags)


int main()
{
foobar f;
qDebug() << "Flags state" << f.getFlag( foobar::flag1 );
f.toggleFlag(foobar::flag1);
qDebug() << "Flags state" << f.getFlag( foobar::flag1 );
}

This is a run:


[elcuco@pinky ~/src/qt4-bugs/testing-flags] make && ./testing-flags
g++ -c -pipe -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fstack-protector --param=ssp-buffer-size=4 -m32 -march=i686 -mtune=atom -fasynchronous-unwind-tables -Wall -W -D_REENTRANT -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -I/usr/lib/qt4/mkspecs/linux-g++ -I. -I/usr/include/QtCore -I/usr/include/QtGui -I/usr/include -I. -I. -o testing-flags.o testing-flags.cpp
g++ -Wl,-O1 -o testing-flags testing-flags.o -lQtGui -lQtCore -lpthread
Flags state false
Flags state false

edit:
arg.ssf?!#@ ?!@$!@$ .... there is a bug in the "toggle" method, this is why it was not working. Finding and fixing it is left to the reader as en exercise. Thanks wysota!

[wysota]

Lol.... ! != ~ ;)