Problems in centering image

programming flash
1

Hi all

I’ve been working on a dynamic slideshow for some time now. I create an empty Movie Clip imgMC and then load pictures into it. Everything worked fine when the images were all the same size, and the dimensions were hardcoded.

Today I tried the same thing with different size images. I’m calculating the position of my imgMC like so:
imgMC._x = (640 - imgMC._width)/2;
imgMC._y = (800 - imgMC._height)/2;

Say, picture A is currently loaded in imgMC and is 180 px wide. When I click on link for picture B (160 px wide), and do a trace on imgMC._width just after I do a loadMovie, it shows 180 instead of 160.

This basically means that the first time I load an image, there is nothing there, and it always shows 0 on trace. This really throws the X and Y coords way off, and my image isn’t centered on the page. Any pointers anyone?

TIA

2

You need to do an onLoad event for the clip, otherwise it is executing before anything ever loads as you’ve noticed.

3

Thanks for your reply Stratification. I’m a little lost, Flash noob you see :slight_smile:

Should I put the code for calculating x and y pos within the onLoad event? I wrote an onLoad function, and traced the _width, but it looks as if it’s never getting called.

4

Actually, thinking about it what you may want to do is set up an onEnterFrame function for the loading clip (or a container). Then test the getBytesLoaded against getBytesTotal for the image you’re loading. Be sure to delete the onEnterFrame once you’re finished with it. A rough example (pseudocode, not real code obviously):

if(getBytesLoaded == getBytesTotal){
calculate the size
delete the onEnterFrame
}

5

Never mind, I took your tip Strat and looked through Flash help. I’m edging closer to centering nirvana I think. Will post l8r if it works out.

6

Yippee!!! Thanks to Stratification for leading me to the correct solution :thumb:

What I was doing was creating a movie clip, and loading an image into it. Instead, I created a MovieClipLoader object. On the Init function of the loader, I could get the dimensions of the image currently being loaded.

So instead of:

this.createEmptyMovieClip(“imgMC”, this.getNextHighestDepth());
imgMC.loadMovie(sImg);

I put:

this.createEmptyMovieClip(“imgMC”, this.getNextHighestDepth());
var image_mcl:MovieClipLoader = new MovieClipLoader();
var mclListener:Object = new Object();
mclListener.onLoadInit = function(target_mc:MovieClip) {
target_mc._x = (640 - target_mc._width)/2;
target_mc._y = (800 - target_mc._height)/2;
target_mc.loadMovie(sImg);
};
image_mcl.addListener(mclListener);
image_mcl.loadClip(sImg, imgMC);

I also changed every occurrence of the line

imgMC.loadMovie(sImg);

to

image_mcl.loadClip(sImg, imgMC);

That helped me in centering my image without hardcoding. Hope this helps others!

Thanks again Stratification.

7

No problem, glad to help.