How to edit QSpinBox through keyboard on Linux

Hello,

I have QSpinBox on my dialog box, but its value can't changed through keyboard on Linux.
I can do that on Windows and MAC OS X.

There is demo example in widget section namely "spinboxes". I have tried that one also. But in that also value can not be changed through keyboard on Linux.

Is there anyone know how to edit QSpinBox through keyboard on Linux? Please guide me!

The phenomenon you describe with QSpinBox not being editable with the keyboard on Linux is a fairly common bug, usually due to a missing input method or a bug in the interaction between Qt and the Linux IME.
If QSpinBox is in read-only mode (setReadOnly(true)), you can't type on the keyboard. Make sure you don't set setReadOnly(true), or you omit that command:
spinBox->setReadOnly(false);