navigationBar change titleView with animation

Question

I would like to change the content of my titleView in the navigationBar to display different kinds of information, for instance a UIsegmentedControl or a UILabel. The change of the information should be a done with a transition (segmentedControl fades out and label fades in).

I tried to add multiple UIViews in the titleView and animate the alpha value, but it's not working.

[self.navigationItem.titleView addSubview:_mainSegmentedControl];

So I tried to change the content during the animation but since the value can't be animated it will be called immediately:

[UIView animateWithDuration:0.2 animations:^{
     _filterSegmentedControl.alpha = 0.0f;} completion:^(BOOL finished) {
            [UIView animateWithDuration:0.3 animations:^{
                self.navigationItem.titleView = _mainSegmentedControl;
                _mainSegmentedControl.alpha = 1.0f;
            }];
}];

Any suggestions?