MooTools Morph “A is Null”

I’ve decided to post all the silly little things that I do and the resolutions to them.

If you’re coming across something like “A is Null” in MooTools – specifically MooTools Morph – make sure that you’re not passing a collection of elements.

For example, $$(’#element_identifier’), whilst only returning one element, will actually return a collection (albeit a collection containing one element!).

The solution is either use

var y = $$('#element_identifier');
var eldMorph = new Fx.Morph(y[0]);

Or use:

var eldMorph = new Fx.Morph($('element_identifier'));

As the single-dollar only returns one element, not a collection of elements.

While these things are obvious, for those who are playing around at the weekend or after work, it can be really frustrating if the answer isn’t a simple Google away.

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