去掉

- (instancetype)initWithFrame:(CGRect)frame childVCs:(NSArray *)childVCs parentVC:(UIViewController *)parentVC delegate:(id<FSPageContentViewDelegate>)delegate
{
    self = [super initWithFrame:frame];
    if (self) {
        self.parentVC = parentVC;
        self.childsVCs 
 
= childVCs;
        self.delegate = delegate;
        
//        [self setupSubViews]; //去掉這個,否則黑屏
    }
    return self;
}

FSPageContentView這個庫需要修改源碼才能用，否則有黑屏bug