Getting two signals inside one slot

[viniltc]

Hi All,

I'm a bit confused getting two signals inside one slot

void Program::nextBtn()
{
    m_currentBtn++;
    if(m_currentBtn > btnGrp->buttons().size())
    {
        m_currentBtn = 0;
    }

    emit buttonChanged(m_currentBtn);  // signal 1
}

void Program::changeValue(int value)
{

    CurPoint1->setY(value);
    CurPoint2->setY(value);
    update();

    emit pulseWidthValue(adjust_PW_range(CurPoint1->y())); // signal 2

}

At present , I do connect:

connect(ui->btn_nextPhase, &QPushButton::clicked, this, &Program::nextBtn);
connect(this, &Program::buttonChanged, this, &Program::paintBtn);

to get value of buttonChanged signal inside paintBtn slot.

But now I need value from pulseWidthValue signal as well inside paintBtn slot..

How do I modify the paintBtn definition to get both the signal values?

Or is there better workaround to this problem?

[mrjj]

Hi
You can simply add the extra parameter to the signal and slot definitions
and emit it with the new value
emit buttonChanged(m_currentBtn, adjust_PW_range(CurPoint1->y()) );
make sure also change paintBtn so it has this extra paramter.

[viniltc]

@mrjj Hi, thanks a lot for your feedback.

I could not find what's the issue with the following scenario that not works:

Not Working - Run time error: One signal implimentation

void nextBtn();
void paintBtn(int id, int pwvalue);

signals:
        void buttonChanged(int id, int pwvalue);

// connections
 connect(ui->btn_nextPhase, &QPushButton::clicked, this, &Program::nextBtn);
 connect(this, &Program::buttonChanged, this, &Program::paintBtn);

void Program::nextBtn()
{
    m_currentBtn++;
    if(m_currentBtn > btnGrp->buttons().size())
    {
        m_currentBtn = 0;
    }

    emit buttonChanged(m_currentBtn, adjust_PW_range(CurPoint1->y()));
}


void Program::paintBtn(int id, int pwvalue)
{
    ui->label_7->setText(QString::number(pwvalue));
}

Working scenario: Two signals

void changeValue(int value );
void nextBtn(int pwvalue);
void paintBtn(int id, int pwvalue);

signals:
        void buttonChanged(int id, int pwvalue);
        void pulseWidthValue(int pwvalue);


 connect(ui->btn_nextPhase, &QPushButton::clicked, this, &ProgramPalmerGrasp::nextBtn);

    connect(this, &Program::buttonChanged, this, &Program::paintBtn);
    connect(this, &Program::pulseWidthValue, this, &Program::nextBtn);


void Program::changeValue(int value)
{

    CurPoint1->setY(value);
    CurPoint2->setY(value);
    update();

    emit pulseWidthValue(adjust_PW_range(CurPoint1->y())); 

}


void Program::nextBtn(int pwvalue)
{
    m_currentBtn++;
    if(m_currentBtn > btnGrp->buttons().size())
    {
        m_currentBtn = 0;
    }

     emit buttonChanged(m_currentBtn, pwvalue);
}

void Program::paintBtn(int id, int pwvalue)
{
    ui->label_7->setText(QString::number(pwvalue));
}

[JonB]

@viniltc said in Getting two signals inside one slot:

Not Working - Run time error: One signal implimentation

What run time error message?

[viniltc]

@JonB , It just stops the application. Even the debug terminal crashes, I cant spot where exactly is the issue ..

[viniltc]

The debug took long time to point at:

emit buttonChanged(m_currentBtn, adjust_PW_range(CurPoint1->y()));

Throws the following message:

[mrjj]

Hi
I would guess on that
emit buttonChanged(m_currentBtn, adjust_PW_range(CurPoint1->y()));

When you call this, you have not yet ALLOCATED CurPoint1

so it crashes.

Make sure its valid at this point in time.

[JonB]

@viniltc
And further to @mrjj, if you run your app from within the debugger it should break on that exception, and give you a stack trace showing you are executing expressionCurPoint1->y().