Button size is not correctly set if it is created inside an element hidden with display: none

[silentnights]

Hi,
The button sizes are not correctly set if it was created in a display: none element. Apparently the size calculation below is not correctly calculating the size if the element has display: none css property:
var width = this.options.width || Math.max($toggleOn.width(), $toggleOff.width())+($toggleHandle.outerWidth()/2)

From the above all width() functions return zero which is not the correct size when the display is set back to block.

This makes the sizes not correct whenever you create the elements inside bootstrap tabs as an example.

I have set an explicit width, which fixes the issue, but I hope there would be a global fix for this.

[CharlieEtienne]

Same here, for example it doesn't work when placed in a modal.

[Deekor]

Yup not working in a bootstrap tab that is hidden at first.

[cahpalencia]

Same problem here when used in hidden tabs.

[Pointotech]

Same problem.

[huyz]

This looks like a duplicate of #106 , which lists an open PR and some forks with solutions.