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javaoopinner-classeslocal-variablesminesweeper

How do I change the variable value in the inner class

I am making a minesweeper game. I want to reduce the number of flags in the inner class but I get this error ."local variables referenced from an inner class must be final or effectively final java".How can I solve this problem ?

Solution

  • You can't reference a variable from the outer class in the inner class if it's not at least effectively final. An effectively final variable is a variable that is guaranteed to never change.

    However, you can wrap your variable. Any kind or wrapper is good. You can transform 'flags' (or whatever you called your variable) into one element array and use it instead:

    final int[] flags = {0};

    Now you can update your variable from the inner class:

    flags[0]++;

    You can also use AtomicInteger or any other kind of wrapper.