Not a real solution. You now have a value that is not
represented
by a slider position. Touching the slider will destroy it with no
way to return to it except by typing the value again.
If you use both slider and direct entry methods, you are aware of the
different behaviour.
If you are aware of the different behaviour, and still use the slider,
you want to change the current value.
If you don't want to change the current value, don't touch the slider.
If you want finer control of your parameters, there are different approaches.