gistfile1.js

$(window).keydown(function(e){
    if (['TEXTAREA', 'INPUT', 'SELECT'].indexOf(e.target.tagName) > -1) {
        return true;
    }
    var KEY_UP = 38
        , KEY_DOWN = 40
        , KEY_LEFT = 37
        , KEY_RIGHT = 39;

    switch (e.keyCode) {
        case KEY_DOWN:
            $scope.setNextItemSelected();
            e.preventDefault();
            break;
        case KEY_UP:
            $scope.setPreviousItemSelected();
            e.preventDefault();
            break;
        case KEY_RIGHT:
            $scope.expandSelected();
            e.preventDefault();
            break;
        case KEY_LEFT:
            $scope.closeSelected();
            e.preventDefault();
            break;
    }
});