Need script to work regardless whether stage is resized

1

So I made a listener that moves around MCs when the stage is resized and it works great. However the script doesn’t work until the stage is resized . Below is the script and I would really appreciate it if you could show me how to get the script to work regardless if the browser is resized.

var stageResizeListener:Object = new Object();
stageResizeListener.onResize = function() {

back_mc._x = Stage.width-back_mc.width;
back_mc._y = (Stage.height+1)/2;
next_mc._x = Stage.width-next_mc._width;
next_mc._y = (Stage.height+1)/2;

};
Stage.align = “TL”;
Stage.scaleMode = “noScale”;
Stage.addListener(stageResizeListener);
Stage.addListener(sizeListener);