fix bug : less than iOS11 crash

README.md

@@ -14,22 +14,9 @@ toast效果图：
 
 # 使用方法
 可以通过CocoaPods导入，支持iOS7及以上。
-pod 'SCIndexView'
-
-### 1.x版本
-1. 创建SCIndexViewConfiguration对象，这个对象用来控制索引的UI样式；
-2. 创建SCIndexView对象，这个对象是索引视图本身，初始化方法必须传入UITableView列表，和SCIndexViewConfiguration对象；
-3. 将SCIndexView索引视图添加到UITableView列表视图的父视图之中，再设置索引视图的数据源。
 
-```
-SCIndexViewConfiguration *indexViewConfiguration = [SCIndexViewConfiguration configuration];
-SCIndexView *indexView = [[SCIndexView alloc] initWithTableView:self.tableView configuration:indexViewConfiguration];
-indexView.translucentForTableViewInNavigationBar = self.translucent;
-[self.view addSubview:indexView];
-indexView.dataSource = indexViewDataSource;
-```
+pod 'SCIndexView'
 
-### 2.x版本
 1. 创建SCIndexViewConfiguration对象，这个对象用来控制索引的UI样式；
 2. 设置UITableView对象的 sc_translucentForTableViewInNavigationBar 和 sc_indexViewConfiguration；
 3. 再设置UITableView对象的索引数据源。

SCIndexView.podspec

@@ -9,7 +9,7 @@
 Pod::Spec.new do |s|
 
   s.name         = "SCIndexView"
-  s.version      = "2.0.1"
+  s.version      = "2.0.2"
   s.summary      = "SCIndexView provide a index view."
   s.description  = "SCIndexView provide a index view like Wechat. It is very easy."
 
@@ -20,7 +20,7 @@ Pod::Spec.new do |s|
 
   s.platform     = :ios, "7.0"
 
-  s.source       = { :git => "https://github.com/TalkingJourney/SCIndexView.git", :tag => "2.0.1" }
+  s.source       = { :git => "https://github.com/TalkingJourney/SCIndexView.git", :tag => "2.0.2" }
 
   s.source_files = "SCIndexView/**/*.{h,m}"
   s.public_header_files = "SCIndexView/**/*.h"

SCIndexView/SCIndexView.h

@@ -44,6 +44,7 @@
 // 索引视图的配置
 @property (nonatomic, strong, readonly) SCIndexViewConfiguration *configuration;
 
+// SCIndexView 会对 tableView 进行 strong 引用，请注意，防止“循环引用”
 - (instancetype)initWithTableView:(UITableView *)tableView configuration:(SCIndexViewConfiguration *)configuration;
 
 @end

SCIndexView/SCIndexView.m

@@ -27,7 +27,7 @@ @interface SCIndexView ()
 
 @property (nonatomic, strong) NSMutableArray<CATextLayer *> *subTextLayers;
 @property (nonatomic, strong) UILabel *indicator;
-@property (nonatomic, weak) UITableView *tableView;
+@property (nonatomic, strong) UITableView *tableView;
 
 // tableView是否实现cellHeight的代理方法
 @property (nonatomic, assign) BOOL tableViewHasCellHeightMethod;

SCIndexView/UITableView+SCIndexView.m

@@ -3,6 +3,14 @@
 #import <objc/runtime.h>
 #import "SCIndexView.h"
 
+@interface SCWeakProxy : NSObject
+
+@property (nonatomic, weak) SCIndexView *indexView;
+
+@end
+@implementation SCWeakProxy
+@end
+
 @interface UITableView () <SCIndexViewDelegate>
 
 @property (nonatomic, strong) SCIndexView *sc_indexView;
@@ -44,15 +52,22 @@ + (void)swizzledSelector:(SEL)swizzledSelector originalSelector:(SEL)originalSel
 - (void)SCIndexView_didMoveToSuperview
 {
     [self SCIndexView_didMoveToSuperview];
-    if (self.superview && self.sc_indexView) {
-        [self.superview addSubview:self.sc_indexView];
+    if (self.sc_indexViewDataSource.count && !self.sc_indexView && self.superview) {
+        SCIndexView *indexView = [[SCIndexView alloc] initWithTableView:self configuration:self.sc_indexViewConfiguration];
+        indexView.translucentForTableViewInNavigationBar = self.sc_translucentForTableViewInNavigationBar;
+        indexView.delegate = self;
+        indexView.dataSource = self.sc_indexViewDataSource;
+        [self.superview addSubview:indexView];
+
+        self.sc_indexView = indexView;
     }
 }
 
 - (void)SCIndexView_removeFromSuperview
 {
     if (self.sc_indexView) {
         [self.sc_indexView removeFromSuperview];
+        self.sc_indexView = nil;
     }
     [self SCIndexView_removeFromSuperview];
 }
@@ -79,14 +94,17 @@ - (NSUInteger)sectionOfIndexView:(SCIndexView *)indexView tableViewDidScroll:(UI
 
 - (SCIndexView *)sc_indexView
 {
-    return objc_getAssociatedObject(self, @selector(sc_indexView));
+    SCWeakProxy *weakProxy = objc_getAssociatedObject(self, @selector(sc_indexView));
+    return weakProxy.indexView;
 }
 
 - (void)setSc_indexView:(SCIndexView *)sc_indexView
 {
     if (self.sc_indexView == sc_indexView) return;
 
-    objc_setAssociatedObject(self, @selector(sc_indexView), sc_indexView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+    SCWeakProxy *weakProxy = [SCWeakProxy new];
+    weakProxy.indexView = sc_indexView;
+    objc_setAssociatedObject(self, @selector(sc_indexView), weakProxy, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
 }
 
 - (SCIndexViewConfiguration *)sc_indexViewConfiguration
@@ -128,6 +146,7 @@ - (void)setSc_translucentForTableViewInNavigationBar:(BOOL)sc_translucentForTabl
     if (self.sc_translucentForTableViewInNavigationBar == sc_translucentForTableViewInNavigationBar) return;
 
     objc_setAssociatedObject(self, @selector(sc_translucentForTableViewInNavigationBar), @(sc_translucentForTableViewInNavigationBar), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+    self.sc_indexView.translucentForTableViewInNavigationBar = sc_translucentForTableViewInNavigationBar;
 }
 
 - (NSArray<NSString *> *)sc_indexViewDataSource
@@ -146,13 +165,12 @@ - (void)setSc_indexViewDataSource:(NSArray<NSString *> *)sc_indexViewDataSource
         return;
     }
 
-    if (!self.sc_indexView) {
+    if (!self.sc_indexView && self.superview) {
         SCIndexView *indexView = [[SCIndexView alloc] initWithTableView:self configuration:self.sc_indexViewConfiguration];
         indexView.translucentForTableViewInNavigationBar = self.sc_translucentForTableViewInNavigationBar;
         indexView.delegate = self;
-        if (self.superview) {
-            [self.superview addSubview:indexView];
-        }
+        [self.superview addSubview:indexView];
+
         self.sc_indexView = indexView;
     }
 

SCIndexViewDemo/SCIndexViewDemo.xcodeproj/project.pbxproj

@@ -353,6 +353,7 @@
 				CODE_SIGN_STYLE = Automatic;
 				DEVELOPMENT_TEAM = 3J3Z9KKCQS;
 				INFOPLIST_FILE = SCIndexViewDemo/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = SC.SCIndexViewDemo;
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -369,6 +370,7 @@
 				CODE_SIGN_STYLE = Automatic;
 				DEVELOPMENT_TEAM = 3J3Z9KKCQS;
 				INFOPLIST_FILE = SCIndexViewDemo/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = SC.SCIndexViewDemo;
 				PRODUCT_NAME = "$(TARGET_NAME)";