variable as object

rktech

  for (int i =1 ;i<5;i++) {
             QString s = QString::number(i);
             ui->("modra"+s)->setAutoDefault(false);
             ui->("modra"+s)->setIcon(QPixmap::fromImage(image));
             ui->("modra"+s)->setIconSize(image.rect().size());
             ui->("modra"+s)->resize(image.size());
       }

I have buttons modra1-modra4. Image image is defined. Is that any way to use i from for cycle to change corresponding button properities?
Thanks
rktech

Christian Ehrlicher

You can search for objects by the object name: QObject::findChild()

rktech

I think, that this is not what I asked. I need a way to create ui->modra1->... if i == 1 and ui->modra2->... if i == 2 ...

Chris Kawa

What @Christian-Ehrlicher said is right. Your example code using it would look like this:

for (int i =1 ;i<5;i++) {
             QString name = "modra" + QString::number(i);
             QPushButton* button = findChild<QPushButton*>(name);
             button->setAutoDefault(false);
             button->setIcon(QPixmap::fromImage(image));
             button->setIconSize(image.rect().size());
             button->resize(image.size());
       }

Kent-Dorfman

huh!? what's wrong with arrays of objects instead of discrete names for each indexed button?

Vector<QPushbutton*> buttonVector(5, nullptr);  // 5 element container
for (auto&  i: buttonVector) { // c++17; access to each element
    i = new QPushButton;
}
// at this point you have a vector of QPushbutton* that are 
// each initialized with a QPushbutton

// direct access by index
// arguably more efficient than searching by char-array name
buttonVector[3]->setIcon(image.rect().size());
buttonVector[1]->resize(image.size);

jsulm

@rktech said in variable as object:

I need a way to create ui->modra1->... if i == 1 and ui->modra2->... if i == 2

This is not possible in C/C++ - variable names are compile time.