I have a problem where I want a text field that by default has the word NAME in it, to become empty when a user clicks on it.

The text field has the instance name 'nam' and is inside a movie with the instance name 'input_text'.

I've searched around and found samples of code where everyone keeps suggesting this:

textboxinstancename.onSetFocus = function() {
    textboxinstancename.text = "";
};

should work. It seems to work for everyone else but me.

I've tried using the following on the first frame of the 'input_text' movie with no luck:

this.input_text.nam.onSetFocus = function() {
    this.input_text.nam.text = ""
}

I've tried putting this on the first frame of the scene, again with no result:

_root.input_text.nam.onSetFocus = function() {
    _root.input_text.nam.text = ""
}

I've tried this in the same manner as the last respectively with both 'this' on the instance and '_root' on the scene (denoted by x):

x.input_text.nam.onSetFocus = function() {
    if (x.input_text.nam.text == "NAME") {
        x.input_text.nam.text = "";
    }
};

Still no luck. Can anyone tell me what I might be doing wrong?