Arguments' type and number agreements when used in connect

[tomy]

Hi all,

Just to explore new stuff, I'd like button 2 to be disabled when button 1 is pressed and enabled when it's released.

int main(int argc, char *argv[])
{
  QApplication app(argc, argv);

  QWidget* window = new QWidget;
  QPushButton* button1 = new QPushButton("Button 1", window);
  QPushButton* button2 = new QPushButton("Button 2", window);

  QHBoxLayout* layout = new QHBoxLayout;
  layout->addWidget(button1);
  layout->addWidget(button2);

  window->setLayout(layout);


  QObject::connect(button1, &QPushButton::pressed, button2, 
  &QPushButton::setDisabled);
  QObject::connect(button1, &QPushButton::released, button2, 
  &QPushButton::setEnabled);
  window->show();

  return app.exec();
}

Here it won't run due to inconsistency in the arguments number (setEnabled/Disabled takes a bool in the absence of one sent by pressed/relased).

How to solve this, if possible using QObject::connect?

[Christian Ehrlicher]

@tomy said in Arguments' type and number agreements when used in connect:

How to solve this, if possible using QObject::connect?

By using a lambda as receiver.

[mrjj]

Hi
Just in case you wonder :)

    QObject::connect(button1, &QPushButton::pressed, this, [button2]() {
        button2->setDisabled(true);
    });

    QObject::connect(button1, &QPushButton::released, this, [button2]() {
        button2->setDisabled(false);
    });

[J.Hilk]

Slight modification to @mrjj code, as the code example is contained inside main, which makes using this as reference pointer impossible.

QObject::connect(button1, &QPushButton::pressed, button2, [button2]()->void {
        button2->setDisabled(true);
    });

    QObject::connect(button1, &QPushButton::released, button2, [button2]()->void {
        button2->setDisabled(false) ;
    });

[tomy]

@J.Hilk
Thanks. I myself also used button2, since it's the original receiver of the signal. Or simply, it's our target.