RN ReactNative 使用 MJRefresh 自定义刷新组件

- (instancetype)init
{
    if ((self = [super init])) {
        [self setRefreshingTarget:self refreshingAction:@selector(refreshControlValueChanged)];
        _isInitialRender = true;
        _currentRefreshingState = false;
    }
    return self;
}

- (void)setFrame:(CGRect)frame {
    CGFloat width = self.scrollView.frame.size.width ?: [UIScreen mainScreen].bounds.size.width;
    CGFloat height = 54;
    [super setFrame:CGRectMake(frame.origin.x, _isInitialRender ? frame.origin.y : -54, width, height)];
}

RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)aDecoder)

- (void)layoutSubviews
{
    [super layoutSubviews];
    self.backgroundColor = [UIColor clearColor];
    if (_currentRefreshingState && _isInitialRender) {
        [self _beginRefreshing];
    }
    _isInitialRender = false;
}

- (void)_beginRefreshing
{
    [self.scrollView.mj_header beginRefreshing];
}

- (void)_endRefreshing
{
    [self.scrollView.mj_header endRefreshing];
    _currentRefreshingState = false;
}

- (NSString *)title
{
  return _title;
}

- (void)setTitle:(NSString *)title
{
  _title = title;
  [self _updateTitle];
}

- (void)setTitleColor:(UIColor *)color
{
  _titleColor = color;
  [self _updateTitle];
}

- (void)_updateTitle
{

}

- (void)setRefreshing:(BOOL)refreshing
{
    
  if (_currentRefreshingState != refreshing) {

    if (refreshing) {
      if (!_isInitialRender) {
        [self _beginRefreshing];
      }
    } else {
      [self _endRefreshing];
    }
  }
}

- (void)refreshControlValueChanged
{
    _currentRefreshingState = true;

  if (_onRefresh) {
    _onRefresh(nil);
  }
}

- (void)setRctRefreshControl:(RCTRefreshControl *)refreshControl
{
    _rctRefreshControl = refreshControl;
    self.mj_header = refreshControl;
}

RCTRefreshControl *refreshControl = _scrollView.rctRefreshControl;
  if (refreshControl && refreshControl.state == MJRefreshStateIdle) {
      refreshControl.frame = CGRectMake(0, -54, self.frame.size.width, 54);
  }