How can I convert an int[ ][ ] to an ArrayList

Question

All transfer procedures between activities appear to be based on ArrayList (even so-called simplified ones, like TinyDB), not Array. My app uses Array (int[ ][ ]). So I'm looking for a way to convert Array into ArrayList, so I can apply one of these transfer procedure.

Answer 1

If you want to preserve the structure of the data, you'll need a List<Integer[]>. Converting a multi-dimensional array to a single-dimensional list will cause data loss.

You could also use a List<List<Integer>>, which would essentially be the same as above.

If you want to preserve your data:

private void foo(int[][] myArrayOfArrays) {
    List<Integer[]> foos = new ArrayList<>();

    for (int myArray[] : myArrayOfArrays) {
        foos.add(myArray);
    }

}

Alternatively, if you don't mind the data loss, you could just list all the items:

private void bar(int[][] foobar) {
    List<Integer> foos = new ArrayList<>();

    for (int[] myArray : foobar) {
        for (int i : myArray) {
            foos.add(i);
        }
        // Possibly add this as a delimiter?
        foos.add(Integer.MAX_VALUE);
    }

}