How does gotoAndStop work for html5 canvas?

Question

I am finding that gotoAndStop will not work properly for an mc if the script is at the root level.

For example, if I have an mc called "bananas" which has ten frames, I can use "this.gotoAndStop(5);" on a script within the timeline of the mc itself and it seems to work.

However if I use "root.bananas.gotoAndStop(5);" from a script at the root of my Animate file, it does not work.

Is that how it is, or maybe I am doing something wrong?

Also, if you have multiple instances of an mc, does that cause problems with gotoAndStop?

Colin Holgate · Accepted Answer

What is the value of root? The main timeline is also 'this' at its level, so this syntax would be more correct:

this.bananas.gotoAndStop(5);

but one potential problem is that at the time that line runs the movieclip hasn't yet arrived on the stage. Putting the script inside the movieclip is an easy solution, but you might want to have it go to a different frame sometimes. That can be done using window variables. Like in the main timeline on that first frame you could have:

window.whichbanana = Math.floor(Math.random()*10);

and inside the bananas movieclip you say:

this.gotoAndStop(window.whichbanana);

Nebulous_Dawn · Answer

Finally got around to re-testing, and got my thing working :-)

Because my canvas has a preloader screen, I was assuming everything was ready as soon as it appeared on the screen, but in fact, although all the assets had loaded, the elements within the canvas were not all constructed.

Originally I had set all the "gotoAndStops" immediately after the canvas had loaded - and nothing was happening.

I did not really need the gotoAndStops to run that early, so I moved them in the code to run later (after the user had clicked a few buttons, a splash screen had come and gone, etc.) - that fixed it.

Here's my final working code:

/* immediately on load */

var root = this;

/* inside a function later on, after the mcs all had time to build */

for (i = 1; i < 13; i++) {

root.text_blocks["text_block_" + i].gotoAndStop(i-1);

}

So it looks as if my code was ok in the first place, except that I had it too early in the file.

Colin's first reply set me on the right track, so I will mark it as the correct answer, but the thread as a whole was very helpful.

Sign up

To post, reply, or follow discussions, please sign in with your Adobe ID.

Sign in to Adobe Community

To post, reply, or follow discussions, please sign in with your Adobe ID.