Transparent GIF hack

Working with DHTML sucks; and that’s a fact of life. The older the browser, the worst it is because of different DOM implementations. I was trying to set this thing up where you can draw a box outline over an image, and send the coordinates to a PHP program through a form. The event handlers worked fine in Mozilla based browsers, but when IE 4 stepped up to the plate, total failure.

It simply would not capture the click events. After much experimentation, I discovered that my empty div covering the image (and handling the mouse events) was really behaving like it was empty, it was letting the mouseevents fall right through the bottom to the image (like a box with a hole in the bottom) If I specified a background color, it worked properly, but then the image was obscured. The fix, a completely transparent gif as the background for that div and presto, IE 4 was happy.

Jonathan Weatherhead

Jonathan Weatherhead is an apt software developer, amateur blogger, internet enthusiast, hobbyist photographer, and casual video gamer.

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