signals and control arrays

[zorro68]

I have programm an array with four Sliders (SLDpaso[i]). I connect each slider with the function setIsoValueInt like this:

connect(SLDpaso[i], SIGNAL(valueChanged(int)), this, SLOT(setIsoValueInt(int)));

connect(SLDpaso[i], SIGNAL(valueChanged(int)), this, SLOT(setIsoValueInt(int)));

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but in setIsoValueInt(int) function I want to know which slider I have used (which [i]). As you know, valueChanged(int) only emit the value of the slider, but not which slider has emitted the signal. How can I do that?

Thks.

PD:Sorry for my bad english

[Wizard]

Use QObject::sender() to identify source of signal.

[marcel]

Or you can use a QSignalMapper, it is safer than sender(). There is an example in the docs.

[zorro68]

I'm reading help about QObject::sender(). But how to, because I want to know the index of the slider but not its name (QObject::sender()->objectName).

thanks for your quick answer.

[marcel]

Whatever....

[Wizard]

You can find sender() in SLDpaso array, or use QSignalMapper. If you have a lot of sliders (more than 50) QSignalMapper may be faster

[zorro68]

I have read obout sender() function and I need more help. I have programm this:

for (int i=0;i<max_contorno;i++){
		connect(SLDpaso[i], SIGNAL(valueChanged(int)), this, SLOT(setIsoValueInt(int)));
}

for (int i=0;i<max_contorno;i++){
		connect(SLDpaso[i], SIGNAL(valueChanged(int)), this, SLOT(setIsoValueInt(int)));
}

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and in setIsoValueInt:

QSlider *SLDp = (QSlider *)sender();

QSlider *SLDp = (QSlider *)sender();

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But i dont know how to obtain the index of the Sliders array

[marcel]

There:

int sldIndex = -1;
for(int i = 0; i != max_contorno; ++i)
  if(SLDpaso[i] == SLDp) 
  {
     sldIndex = i;
     break;
  }

int sldIndex = -1;
for(int i = 0; i != max_contorno; ++i)
  if(SLDpaso[i] == SLDp) 
  {
     sldIndex = i;
     break;
  }

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So, you should test sldIndex to be a valid value.

Regards

[zorro68]

Marcel, this works fine. Thanks very very much.