Custome destructor in C++

[Ahti]

I am developing an app in which I start a timer in constructor and stop it in destructor but I get an error namely:

'class Example' has no member named 'level'.

My Code:

Example.h

class Example: public QObject
{
    Q_OBJECT

    public:

        explicit Example(QObject *parent = 0);    
        ~Example();
    ... 
}

Example.cpp:

Example::Example(QObject *parent) : QObject(parent)
{
    timer = new QTimer(this);
    connect(timer, SIGNAL(timeout()),this,SLOT(update_func()));
    timer->start(1000);
}

Example::~Example(){
    timer->stop();
}

please help.

[SGaist]

Hi,

Do you have any "level" variable somewhere that you are calling ?

[Ahti]

@SGaist yes in header this:

Q_PROPERTY(int level READ level WRITE set_level NOTIFY level_changed)

[SGaist]

Did you properly declare all the methods and implement the slot and getter ?

[Ahti]

@SGaist I think so:

void Example::set_level(int level){
    if (level != g_level){
        g_level = level;
        emit level_changed(g_level);
    }
}

void Example::update_func(){
    int level = get_level();
    if (level != INVALID){
        set_level(level);
    }
}

int Example::cur_level(){
    return g_level;
}

[SGaist]

You declared the getter method to be level. I don't see that method anywhere in your code.

[Ahti]

@SGaist What Is a getter ?

[JKSH]

@Ahti said in Custome destructor in C++:

What Is a getter ?

In your header, you wrote this:

Q_PROPERTY(int level READ level WRITE set_level NOTIFY level_changed)

You're saying that you have these functions:

• Getter method (READ): level()
• Setter method (WRITE): set_level()
• Signal (NOTIFY): level_changed()

You told Qt that your getter is called level(), but it is actually called cur_level().

[Ahti]

@JKSH @SGaist Please answer this question https://forum.qt.io/topic/104014/how-to-update-qml-control-periodically-from-c-code/2