1，切换分类后，会重置前一个分类的筛选

2，切换tab以及返回前台后，将重新选中首个分类，并重置所有分类的筛选

iCemarose/Class/Model/KWMCategoryModel.h

@@ -22,5 +22,7 @@
 @property (nonatomic) NSMutableArray<KWMFilter *> *filters;
 @property (nonatomic) NSString *brand;
 @property (nonatomic) CGFloat offsetY;
+//切换分类后，如果原来有选中筛选规则的需要清除并重新刷新，以此字段标识
+@property (nonatomic) BOOL isNeedReload;
 
 @end

iCemarose/Class/UI/Category/KWMCategoryVC.m

@@ -64,6 +64,7 @@
 
 - (void)viewDidLoad {
     [super viewDidLoad];
+    [self registerResetPageNotification];
     [self initData];
     [self initView];
     [self requestAllBrandsApi];
@@ -85,6 +86,14 @@
     [self.navigationController setNavigationBarHidden:NO];
 }
 
+-(void)dealloc{
+    //如果大于等于ios9.0，不需要反注册了，从ios9.0开始通知中心会对观察者弱引用
+    NSString *version = [UIDevice currentDevice].systemVersion;
+    if (version.doubleValue < 9.0) {
+        [self unRegisterNotification];
+    }
+}
+
 -(KWMCollectionRefreshUtil *)refreshUtil{
     if(!_refreshUtil){
         _refreshUtil = [KWMCollectionRefreshUtil new];
@@ -161,6 +170,66 @@
     [self initCustomTitleBarConstarints:self.titleView];
 }
 
+#pragma mark -- resetFilter resetPager
+/* 每次切换tab和从首页重新回来的时候，都会清空筛选和选回首个分类
+   每次切换分类，都会清空掉该分类的筛选 */
+
+//注册and反注册 重置筛选和选中分类的广播
+-(void)registerResetPageNotification{
+    //从后台返回前台时
+    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(resetPager)name:UIApplicationWillEnterForegroundNotification object:nil];
+    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(resetPager)name:@"didSelectCategoryTab" object:nil];
+}
+
+-(void)unRegisterNotification{
+    [[NSNotificationCenter defaultCenter] removeObserver:self];
+}
+
+-(void)resetPager{
+    [self resetAllOffset];
+    [self resetAllFilter];
+    [self resetCategorySelected];
+}
+
+//移除筛选
+//需要被重置的分类，标示isNeedReload，下次进入时，刷新
+-(void)resetAllFilter{
+    for (KWMCategoryModel *category in self.categories) {
+        BOOL isNeedReload = NO;
+        if(category.filters && category.filters.count > 0){
+            [category.filters removeAllObjects];
+            isNeedReload = YES;
+        }
+        if(category.sort != BUYCollectionSortCollectionDefault){
+            category.sort = BUYCollectionSortCollectionDefault;
+            isNeedReload = YES;
+        }
+        if(category.brand){
+            category.brand = nil;
+            isNeedReload = YES;
+        }
+        if(isNeedReload){
+            category.isNeedReload = YES;
+            category.offsetY = 0;
+        }
+    }
+}
+
+-(void)resetAllOffset{
+    self.cvRightProduct.contentOffset = CGPointMake(0, 0);
+    for (KWMCategoryModel *category in self.categories) {
+        category.offsetY = 0;
+    }
+}
+
+-(void)resetCategorySelected{
+    self.selectedCategory = self.categories.firstObject;
+    NSIndexPath * path = [NSIndexPath indexPathForItem:0 inSection:0];
+    if([self.tbvLeftCategory numberOfRowsInSection:0]>0){
+        [self.tbvLeftCategory selectRowAtIndexPath:path animated:YES scrollPosition:UITableViewScrollPositionTop];
+    }
+}
+
 #pragma mark -- KWMCategoryTitleDelegate
 -(void)kwm_onClickShopCart{
     KWMShopCartVC * shopCartVC = (KWMShopCartVC*)[KWMBaseVC findControllerBy:[KWMShopCartVC kwmTag] fromStoryboard:@"ShopCart"];
@@ -191,6 +260,7 @@
 //    [self.cvRightProduct.mj_header endRefreshing];
 //    [self.cvRightProduct.mj_footer endRefreshing];
     self.selectedCategory = self.categories[indexPath.row];
+    [self resetAllFilter];
 }
 
 #pragma mark - UICollectionViewDataSource
@@ -316,6 +386,7 @@
     self.filterTab.userInteractionEnabled = false;
     
     KWMCategoryModel *cmodel = self.selectedCategory;
+    cmodel.isNeedReload = NO;
     NSMutableArray *tags = [KWMFilterUtil getTagsByFilterArray:cmodel.filters];
     if(cmodel.brand){
         [tags addObject:cmodel.brand];
@@ -384,6 +455,8 @@
         }else{
             [self.cvRightProduct.mj_header beginRefreshing];
         }
+    }else if(_selectedCategory.isNeedReload){
+        [self.refreshUtil reLoadData];
     }else if([self.cvRightProduct.mj_header isRefreshing]) {
         [self.cvRightProduct.mj_header endRefreshing];
     }

iCemarose/Class/UI/KWMMainVC.m

@@ -181,6 +181,7 @@
     tabBarItem2.image = image2;
     image2 = [[UIImage imageNamed:@"btn_tab_store_pre"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
     tabBarItem2.selectedImage = image2;
+    tabBarItem2.tag = 101;
     
     
     UIImage *image3 = [[UIImage imageNamed:@"btn_tab_ brand"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
@@ -216,6 +217,12 @@
     
 }
 
-
+- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item{
+    // 这里不需要调用super，因为父类没有实现这个代理方法
+    //[super tabBar:tabBar didSelectItem:item];
+    if(item.tag == 101){
+        [[NSNotificationCenter defaultCenter] postNotificationName:@"didSelectCategoryTab" object:nil];
+    }
+}
 
 @end