Selection.setFocus Selection.getFocus inputting from mc

i am attaching a number of _mc (my_mc) with a for loop. Inside each my_mc is an input textfield (my_txt)

I want to click on my_mc.my_txt and select the textfield .the following code allow this and i can enter text from the keyboard however I want to add text from a _mc keybooard on screen (here called myBtn_mc).

As soon as I click on myBtn_mc of course I lose focus … i have tried to use a variable (select) to keep scope&focus … I keep focus but can not add text via screen _mc

many thanks Neil