How to animate view iOS

- (void)showErrorView
{
    if (self.errorView.hidden) {
        self.errorView.alpha = 0.0;
        self.errorView.hidden = NO;

        [UIView animateWithDuration:0.3 animations:^{
            self.contentView.alpha = 0.0;
            self.errorView.alpha = 1.0;
        } completion:^(BOOL finished) {
            self.contentView.hidden = YES;
            self.noResultsView.hidden = YES;
            self.offlineView.hidden = YES;
        }];
    }
}