Question

I created 2 rows of push buttons, each row is inside a QHBoxLayout.

I create the buttons in the code:

static const char* buttonText = "23456789TJQKA";
for (int ii = 0; buttonText[ii]; ii++)
{
    QPushButton* pushButton = new QPushButton(this);
    pushButton->setText(QString(buttonText[ii]));
    ui->horizontalLayout_1->addWidget(pushButton);
}
for (int ii = 0; buttonText[ii]; ii++)
{
    QPushButton* pushButton = new QPushButton(this);
    pushButton->setText(QString(buttonText[ii]));
    ui->horizontalLayout_2->addWidget(pushButton);
}

The problem is that they can’t shrink (when the user resizes the dialog) beyond that size, even though their text would fit in a much smaller width. If I create the buttons manually in the resource editor instead of in the code, they can have smaller width than that.

Answer 1

This happens because the minimumSizeHint of the QPushButton does not allow the QLayout to resize it :

The default implementation of minimumSizeHint() returns an invalid
size if there is no layout for this widget, and returns the layout’s
minimum size otherwise. Most built-in widgets reimplement
minimumSizeHint().

QLayout will never resize a widget to a size smaller than the minimum
size hint unless minimumSize() is set or the size policy is set to
QSizePolicy::Ignore. If minimumSize() is set, the minimum size hint
will be ignored.

The simple solution is to set the minimum width explicitly:

static const char* buttonText = "23456789TJQKA";
for (int ii = 0; buttonText[ii]; ii++)
{
   QPushButton* pushButton = new QPushButton(this);
   pushButton->setMinimumWidth(5);
   pushButton->setText(QString(buttonText[ii]));
   ui->horizontalLayout_1->addWidget(pushButton);
}
for (int ii = 0; buttonText[ii]; ii++)
{
   QPushButton* pushButton = new QPushButton(this);
   pushButton->setMinimumWidth(5);
   pushButton->setText(QString(buttonText[ii]));
   ui->horizontalLayout_2->addWidget(pushButton);
}