如何获取特定布局的所有QPushButton

Question

I would like to know how to get all QPushButtons of a specific Layout.

Here is my code (doesn't work)

QList<QPushButton *> step2PButtons = findChildren<QPushButton *>(step2Layout);
for (auto *button: step2PButtons )
    button->setEnabled(false);

I have the following error :

no matching function for call to 'MainWindow::findChildren(QVBoxLayout*&)'

I can get all the elements of my interface, but i cannot get elements of a specific layout.

Thanks for helping

Answer 1

How about this:

QList<QPushButton*> step2PButtons = step2Layout->findChildren<QPushButton*>();
for(auto it = step2PButtons.begin(); it != step2PButtons.end(); ++it)
    (*it)->setEnabled(false);

I'm guessing step2Layout is a pointer to a QVBoxLayout object.

It's a member function of QObject , which step2Layout is derived from. You're calling it from QMainWindow , and that's why you're getting all Window buttons.

Answer 2

The Quantum Physicist's answer is correct but one small detail is missing: when you create a layout with Qt Designer, if you look at the generated code you will see that it creates a "hidden" QWidget, parent to the layout:

QWidget *verticalLayoutWidget;
QVBoxLayout *verticalLayout;
[...]
verticalLayoutWidget = new QWidget(centralWidget);

Then the button that you think is child of the layout is actually not, it is child of this hidden widget.

pushButton = new QPushButton(verticalLayoutWidget);

If you replace step2Layout->findChildren<QPushButton*>(); by step2Layout->parentWidget()->findChildren<QPushButton*>(); you should get the buttons that are in your layout and can process them in the loop.