How to take one field time and add 3 minutes in another?

I would like to know how to get the time from the txt_hora field and go to txt_hora2 by adding +3 minutes. In case in field one would be 9:50 and switch to the other 9:53.

Here I enter the Time

Andafterclicking"GO" it falls on this screen

Accordingtotheimage,Ineedtotransferthefirsthourtotheotherfields,butcounting+3minutes.Itriedtodothis,butIcouldnot:

txt_hora2.setText("" + (Integer.parseInt(txt_hora.getText()) + 3));

and this too:

txt_hora2.setText("" + (Integer.parseInt(txt_hora.getText()) + (1000 * 60 * 3)));