Interactive–Fade In / Fade Out

Question

I am working on creating an interactive map. When a button is clicked a circle graphic fades in. When the same button is clicked I want the graphic to fade out the same way. I can only figure out how to make the graphic instantly disappear instead of fading out.
I am following a tutorial and changing it to my needs. The tutorial can be seen here: http://flashexplained.com/design/making-an-interactive-country-map/
The steps for the animation start at step 8.
Here is the code I am using:
button_btn.onPress = function() {
if (popDensity._visible == false) {
popDensity._visible = true;
popDensity.play();
} else {
popDensity._visible = false;
popDensity.gotoAndStop(1);
I am using Flash CS3 and Action Script 2.0.
I would also like to have the circle graphic have a small photo pop up by it when the mouse hovers over it. What do I need to look into to make something like this happen? I haven't been able to find anything similar to doing this.
Thank you for any help you might have.

Answer 1

If you used a timeline tween to make the object gradually appear, then you can make one that builds off the end of it that makes it fade out.  You just tell it to play again.  So you won't necessarily need the _visible code for the button anymore.  In your animation you can use
// in frame 1 of the animation
stop();
this._visible = false;
// in frame 2
this._visible = true;
// the frame where it is fully faded in
stop();
// and your button code...
button_btn.onPress = function() {
     popDensity.play();
So the object starts out invisible sitting stopped at frame 1, you click the button and the animation plays, turning visible at frame 2 and fading in until it stops when it is fully visible.  You click the button again and it plays to fade out, looping back to stop at frame 1 and turn invisible again.  There are other approaches, so maybe you can think of something else as you go.
You actually do not need to make the object visible/invisible with this approach because it is not being used as part of the control logic.