iOS开发中TabBar再次点击实现刷新效果

- (void)layoutSubviews
{
 [super layoutSubviews];
 for (UIButton * tabBarButton in self.subviews) {
  if ([tabBarButton isKindOfClass:NSClassFromString(@"UITabBarButton")]) {
   //监听tabbar的点击
   //绑定tag 标识
   tabBarButton.tag = index;
   //监听tabbar的点击
   [tabBarButton addTarget:self action:@selector(tabBarButtonClick:) forControlEvents:UIControlEventTouchUpInside];
  }
 }
}

- (void)tabBarButtonClick:(UIControl *)tabBarBtn{
 
 //判断当前按钮是否为上一个按钮
 //再次点击同一个item时发送通知出去 对应的VC捕获并判断
 if (self.previousClickedTag == tabBarBtn.tag) {
  
  [[NSNotificationCenter defaultCenter] postNotificationName:
   @"DoubleClickTabbarItemNotification" object:@(tabBarBtn.tag)];
 }
 self.previousClickedTag = tabBarBtn.tag;
}

- (void)viewDidLoad {
 [super viewDidLoad];
 [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(doubleClickTab:) name:@"DoubleClickTabbarItemNotification" object:nil];
}

-(void)doubleClickTab:(NSNotification *)notification{
 //这里有个坑 就是直接用NSInteger接收会有问题 数字不对
 //因为上个界面传过来的时候封装成了对象，所以用NSNumber接收后再取值
 NSNumber *index = notification.object;
 if ([index intValue] == 1) {
  //刷新
 }
}