java - How to limit number of checkboxes that can be checked? -

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i have 4 checkboxes. want user select 2 of them. how set limit?

you can have int variable stores how many checkboxes checked... time oncheckedchanged() called, check variable , if third checkbox checked, set unchecked again...

let's start checkboxes unchecked. do:

int numberofcheckboxeschecked = 0;

then set oncheckchangedlistener:

checkbox1.setoncheckedchangelistener(new oncheckedchangelistener() {     @override     public void oncheckedchanged(compoundbutton buttonview, boolean ischecked) {         if (ischecked && numberofcheckboxeschecked >= 2) {             checkbox1.setchecked(false);         } else {             // checkbox either got unchecked             // or there less 2 other checkboxes checked             // change counter accordingly             if (ischecked) {                 numberofcheckboxeschecked++;             } else {                 numberofcheckboxeschecked--;             }              // fine , can whatever             // checking checkbox should here         }     } });

(i have not tested code, should work.)


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