Dynamic text field: swap text with diff variable in same ext. file

programming flash
1

I’m using the recommended

loadText = new LoadVars();
loadText.load(_global.text_url2);
loadText.onLoad = function(success) {
    if(success){	}

etc..

which is working well. I just want to attach an action to buttons which will switch the text for different variables in the same text file, in a single text box named

archivetitle

.

ie.

archivetitle.text = this.title1;

when button one is pressed

archivetitle.text = this.title2;

when button two is pressed.

Basically, how do i access an already loaded text object to refresh to a new variable? Thanks!