SpinBox and virtual Keyboard

[Till Orly]

Hi community,

I'm kind of a QT noob. I need a virtual keyboard, and it should be Qt widgets (customer want it that way).

Now I found an easy to use and reuse approach from TI (http://processors.wiki.ti.com/index.php/Qt_Keyboard_Template) they open it using the selectionChanged() slot of a QLineEdit.

Now what' the most QT way to open it when clicking into any SpinBox?

Cheers Tillo

[mrjj]

Hi
The very right way would be via
http://doc.qt.io/qt-5/qinputmethod.html#details
for true integration. ( as far as i know. not tried that class)

However, if you only need for SpinBox, then maybe event filter to catch the click
(pseudo code - yours is most likely MainWindow and not QDialog)

in ctor
ui->spinBox->installEventFilter(this);
...
bool Dialog::eventFilter(QObject *o, QEvent *e)
{
	if (o == spinBox && e->type() ==  QEvent::MouseButtonPress ) {
		e->ignore();
               // pop keyboard
		return true;
	}
	return QDialog::eventFilter(o, e);
}

alternative

you can get its lineEdit and maybe do the same as sample ?
QLineEdit *LE= ui->spinBox->findChild<QLineEdit*>();
if (LE) {
connect like sample
}

[Till Orly]

Thanks, the alternative worked like a charm.

[Till Orly]

@mrjj Actually the alternative had a flaw. Since it uses selectionChanged() and the text in a SpinBox get selected when clicking on one of the arrows...

The solution I came up with, using customContextMenuRequested():

    spinBox->setContextMenuPolicy(Qt::CustomContextMenu);
    connect(spinBox,&QLineEdit::customContextMenuRequested,this,&dialog::openKbLineEdit);

and the fitting slot

void dialog::openKbLineEdit()
{
    QLineEdit *line;
    if(typeid(sender()) != typeid(QLineEdit)){
        line = sender()->findChild<QLineEdit*>();
    } else{
        line = (QLineEdit *)sender();
    }
    lineEditkeyboard->setLineEdit(line);
    lineEditkeyboard->show();
}

Oh, yeah no .ui involved here.

[mrjj]

Super
but i wish you would use
qobject_cast
and not c cast. in
line = (QLineEdit *)sender();

But im just old school :)
As c cast are bad and qobject_cast is the way to cast Qt types.

[SGaist]

@mrjj it's not old school, qobject_cast is the right tool when casting QObject based objects.

C style cast doesn't offer any guarantee that you are casting anything compatible.

[mrjj]

@SGaist

Thanks. It came out wrong.