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javascriptjquerydomimage-loading

My image is done loading, but its height and width have not yet been updated. When does this happen?

I'm using a jQuery plugin that invokes a callback once all images on page have been loaded. It checks the imageObject.complete property and binds a handler to the load and error events to determine when image loading is done.

This works well, but the problem I'm running into is that, even though an image is considered loaded, when I inspect the height and width properties of the image or its containing div element, the dimensions have not yet been updated.

Here's an example:

http://jsfiddle.net/RtnVx/12/

How can I ensure that the containing element has been resized to fit the image before attempting to access its height and width dimensions?

EDIT 1: I cleaned up and commented the code in my jsfiddle to make the example easier to understand.

EDIT 2: There must be a race condition or variation based on caching because when I run the code from a different machine, it works properly (i.e., the top margin is calculated properly), which is actually not good because it is not consistent. The inconsistencies are more apparent in Chrome, FWIW.

Also, to be clear, the goal isn't to call init every time an image loads; rather, init should be called once after all images have been loaded via the AJAX load invocation.

Solution

  • Answer: http://jsfiddle.net/morrison/RtnVx/30/

    You needed to not call batchImageLoad until the image was done loading. I created an event on the loaded image.

    Updated Notes:

    • I cut out your jQuery plug-in. It was overly complex and I didn't completely understand it.
    • My current solution provides error handling by using the error event, as did the plug-in.
    • The solution process:
      • Find all the img's descending from #slides and store that length in a .data() attribute, as well as a variable to keep how many have loaded.
      • Bind a load and error events on each img which updates the count of loaded images.
      • If the count of loaded/errored images hits the total image count, call setTimeout() until all of them have widths greater than zero then fire init().