QDebug & QFlags - pretty text?

Dariusz

Hey

One of the odd ones... so if I add a macro to my enum class to treat it as flag using qt system. How can I then configure its print to be more "pretty" ?

enum class testX {
    flagA,
    flagB,
    flagC
};
Q_DECLARE_FLAGS(amazing, testX)
Q_DECLARE_OPERATORS_FOR_FLAGS(amazing)

inline QDebug operator<<(QDebug &stream, const testX &flag){
    stream<<"LEL2";
    return stream;
}
inline QDebug operator<<(QDebug &stream, const amazing &flag){
    stream<<"LEL";
    return stream;
}

The example above + this code yeld this result :

    amazing f;
    f = testX::flagA | testX::flagC;
    qDebug() << f; /// QFlags(0x1|0x4|0x20)  < how to make this pretty? - also why do I get 3 items and not 2? (its print from different test but using 2 items as well - values here will beoff)
    qDebug() << testX::flagA; /// gives correct LEL2 output from overload above

TIA

Looks like adding :

Q_DECLARE_METATYPE(testX)
Q_DECLARE_METATYPE(amazing)

Have helped a bit, at least with QVariant conversions... also my qDebug gets called properly on
inline QDebug operator<<(QDebug &stream, const amazing &flag){}

but when I try :

inline QDebug operator<<(QDebug &stream, const amazing &flag) {
    stream << "(";
    switch (flag) {
        case testX::flagA: {
            stream << "flagA ";
        }
}

I get error with
value of type xx is not implicitly convertible to QFlags::int(aka int)
and I have no idea what to do with it O_o.

Seems like doing

inline QDebug operator<<(QDebug &stream, const amazing &flag) {
    stream << "(";
        if(flag.testFlag(testX::flagA) {
            stream << "flagA ";
        }

Sorta works... but I'm getting weird flags.. do I need to number each item in my enum 1/2/4/8/16 etc etc? /// seems to be the case... also there seem to be a limit... I cant have 100+ flags :- (

jsulm

@Dariusz said in QDebug & QFlags - pretty text?:

I cant have 100+ flags :- (

Why do you want to have so many flags in one property?
"do I need to number each item in my enum 1/2/4/8/16" - yes, if you want to combine several flags in one variable. Flags use OR to set a flag, AND to unset the flag. This is why each flag must have its own bit in a the integer value:

// Set flag 0x01 with some other flags already set
01010000 OR 00000001 = 01010001
// Unset same flag keeping other flags
01010001 AND 11111110 = 01010000

"but I'm getting weird flags" - what do you mean by that?

israelins85

try:

inline QDebug operator<<(QDebug &stream, const amazing &flag) {
    if (!flag) {
        return stream << testX(0x00);
    }

    amazing l_copy = flag;
    testX l_bit = testX(0x01);

    stream.noquote().nospace() << "(";

    forever {
        if (l_copy.testFlag(l_bit)) {
            stream.noquote().nospace() << l_bit;
            l_copy.setFlag(l_bit, false);
            if (!l_copy) break;
            stream.noquote().nospace() << "|";
        }
        l_bit = testX(qint32(l_bit) << 1);
    }

    stream.noquote().nospace() << ")";

    return stream;
}