How to set the widget has the default focus properties

[Qt_crazyer]

I want to have a default focus on a widget when the program is running. For example, I joined QLineEdit_1 and QLineEdit_2. When the program is running, the default focus is always displayed in QLineEdit_1 above, how to set QLineEdit_2 to get the focus firstly?
Thanks in advance for any advice.

[vivaladav]

Probably what you need is setFocusProxy.

If that doesn't work you can set the focus "manually" after the widget has been shown.

[Vinod Kuntoji]

@Qt_crazyer ,

Hi,

lineEdit2->setFocus();

[Qt_crazyer]

I have used this function. But it doesn't work.

study::study(QWidget *parent)
    : QMainWindow(parent)
{
    widget = new QWidget;
    l1 = new QLineEdit;
    l2 = new QLineEdit;
    m1 = new QLabel(tr("Label1"));
    m2 = new QLabel(tr("Lable2"));
    lay = new QHBoxLayout(widget);
    lay->addWidget(m1);
    lay->addWidget(l1);
    lay->addWidget(m2);
    lay->addWidget(l2);
    lay->setSpacing(10);
    lay->setMargin(10);
    l2->setFocus();
    this->setCentralWidget(widget);
}

Should this function be used here?

[Taz742]

@Qt_crazyer
Please try l2->setFocus(Qt::otherFocusReason);

[Qt_crazyer]

@Taz742
Yes, I have also tried this function, but it doesn't work. This is just a sample program, it is very simple. I do not understand why?...

[Taz742]

@Qt_crazyer
An other solution is to use a singleShot timer :

QTimer::singleShot(0,lineEdit,SLOT(setFocus()));

The focus will then be set once the application is free.

See solution follow the link..

[vivaladav]

@Qt_crazyer I am assuming l2 is a member (using "m" as prefix for members would help).

Just set the focus with a delay, in your case:

    QTimer::singleShot(0, this, [this]
    {
        l2->setFocus();
    });

[Qt_crazyer]

@Taz742
Thank you so much. The problem has been solved. Thank you for your patient guidance.

[Qt_crazyer]

@vivaladav
Thank you for your reply. This method is really effective.

[Taz742]

@Qt_crazyer
Nope. Do not forget mark this topic as SOLVED.

[mpergand]

What about this ?

setTabOrder(l2,l1);

[Qt_crazyer]

@mpergand
Thank you for your advice. I have tried this function. This is indeed an effective way.

[vivaladav]

Keep in mind that setTabOrder might not be the right solution if you introduce more widgets (as in any normal working application).