change way to Get initialized tabbar if exists.

Author: ChenYilong

CYLTabBarController.xcodeproj/project.xcworkspace/xcuserdata/chenyilong.xcuserdatad/UserInterfaceState.xcuserstate

@@ -20,11 +20,11 @@
             ignoreCount = "0"
             continueAfterRunningActions = "No"
             filePath = "Example/CYLTabBarControllerConfig.m"
-            timestampString = "482294547.088128"
+            timestampString = "482295802.220628"
             startingColumnNumber = "9223372036854775807"
             endingColumnNumber = "9223372036854775807"
-            startingLineNumber = "214"
-            endingLineNumber = "214"
+            startingLineNumber = "218"
+            endingLineNumber = "218"
             landmarkName = "-dealloc"
             landmarkType = "5">
          </BreakpointContent>
@@ -45,5 +45,21 @@
             landmarkType = "5">
          </BreakpointContent>
       </BreakpointProxy>
+      <BreakpointProxy
+         BreakpointExtensionID = "Xcode.Breakpoint.FileBreakpoint">
+         <BreakpointContent
+            shouldBeEnabled = "Yes"
+            ignoreCount = "0"
+            continueAfterRunningActions = "No"
+            filePath = "Example/CYLTabBarControllerConfig.m"
+            timestampString = "482295636.508473"
+            startingColumnNumber = "9223372036854775807"
+            endingColumnNumber = "9223372036854775807"
+            startingLineNumber = "179"
+            endingLineNumber = "179"
+            landmarkName = "-customizeTabBarSelectionIndicatorImage"
+            landmarkType = "5">
+         </BreakpointContent>
+      </BreakpointProxy>
    </Breakpoints>
 </Bucket>

CYLTabBarController.xcodeproj/xcuserdata/chenyilong.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist

@@ -174,10 +174,13 @@ - (void)updateTabBarCustomizationWhenTabBarItemWidthDidUpdate {
 
 - (void)customizeTabBarSelectionIndicatorImage {
     //Get Default TabBar Height
-    UITabBarController *tabBarController = [[UITabBarController alloc] init];
+    UITabBarController *tabBarController;
+    tabBarController = [self cyl_tabBarController] ?: [[UITabBarController alloc] init];
     CGFloat tabBarHeight = tabBarController.tabBar.frame.size.height;
     CGSize selectionIndicatorImageSize = CGSizeMake(CYLTabBarItemWidth, tabBarHeight);
-    [[self cyl_tabBarController].tabBar setSelectionIndicatorImage:[[self class]
+    //Get initialized tabbar if exists.
+    UITabBar *tabBar = [self cyl_tabBarController].tabBar ?: [UITabBar appearance];
+    [tabBar setSelectionIndicatorImage:[[self class]
                                                                     imageFromColor:[UIColor yellowColor]
                                                                     forSize:selectionIndicatorImageSize
                                                                     withCornerRadius:0]];