private void init() {
        final ContextThemeWrapper ctw = new ContextThemeWrapper(getContext(), R.style.cgeo);
        inflate(ctw, R.layout.checkboxmatrix_view, this);
        binding = CheckboxmatrixViewBinding.bind(this);
        matrixGrid = binding.matrix;
    }
This view displays and maintains a matrix of checkboxes
main/src/main/java/cgeo/geocaching/ui/CheckboxMatrixView.java