java - Add listener to ArrayList -

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i have arraylist add objects dynamically, , have jbutton. arraylist empty when running program , jbutton set setenabled(false). want enable button whenever there 2 elements in arraylist or more , disable again if arraylist has 1 item or empty. how can achieve this?

arraylist doesn't have sort of notification mechanism.

i suggest write own list implementation delegates private arraylist storage, adds ability listen notifications... or find similar within java itself. defaultlistmodel may work you, although doesn't implement list itself.





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