优化注释

GMBase/Classes/UIView+NavigationShadow.h

@@ -7,7 +7,7 @@
 
 #import <UIKit/UIKit.h>
 
-
+// 注意只适用于UI规范中的导航范围：导航栏阴影，segment切换的阴影。
 @interface UIView (NavigationShadow)
 
 /**

GMBase/Classes/UIView+NavigationShadow.m

@@ -17,43 +17,27 @@
 @implementation UIView (NavigationShadow)
 - (void)addNavigationShadow {
     self.layer.masksToBounds = NO;
-//    self.layer.shadowOpacity = 1.0f;
-//    self.layer.shadowRadius = 2.0f;
-//    self.layer.shadowOffset = CGSizeMake(0.0, ONE_PIXEL);
-//    self.isShowShadow = YES;
-//    self.hideTopShadow = YES;
-
-//    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, self.bounds.size.height - 12, Constant.screenWidth, 12)];
-//    view.backgroundColor = [UIColor whiteColor];
-//    view.autoresizingMask = UIViewAutoresizingFlexibleTopMargin;
-//    [self addSubview:view];
-//    [self sendSubviewToBack:view];
-//    view.layer.masksToBounds = NO;
-//    view.layer.shadowOpacity = 1.0f;
-//    view.layer.shadowRadius = 2.0f;
-//    view.layer.shadowOffset = CGSizeMake(0.0, ONE_PIXEL);
-//    //view.isShowShadow = YES;
-//    view.layer.shadowColor = [UIColor colorWithWhite:0 alpha:0.1].CGColor;
 
     self.shadowLayer = [CALayer layer];
     self.shadowLayer.bounds = CGRectMake(0, 0, Constant.screenWidth, 12);
     self.shadowLayer.position = CGPointMake(self.bounds.size.width/2, self.bounds.size.height - 6);
     self.shadowLayer.backgroundColor = [UIColor whiteColor].CGColor;
-    [self.layer insertSublayer:self.shadowLayer atIndex:0];
     self.shadowLayer.masksToBounds = NO;
     self.shadowLayer.shadowOpacity = 1.0f;
     self.shadowLayer.shadowRadius = 2.0f;
     self.shadowLayer.shadowOffset = CGSizeMake(0.0, ONE_PIXEL);
     self.isShowShadow = YES;
     self.shadowLayer.shadowPath = CGPathCreateWithRect(CGRectMake(0, self.shadowLayer.bounds.size.height - 6, Constant.screenWidth, 6), nil);
+    self.shadowLayer.shadowColor = [UIColor colorWithWhite:0 alpha:0.1].CGColor;
+
 }
 
 - (void)setIsShowShadow:(BOOL)isShowShadow {
     objc_setAssociatedObject(self, @selector(isShowShadow), @(isShowShadow), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
-    if (isShowShadow) {
-        self.shadowLayer.shadowColor = [UIColor colorWithWhite:0 alpha:0.1].CGColor;
-    } else {
-        self.shadowLayer.shadowColor = [UIColor clearColor].CGColor;
+    if (isShowShadow && self.shadowLayer.superlayer == nil) {
+        [self.layer insertSublayer:self.shadowLayer atIndex:0];
+
+    } else if (!isShowShadow && self.shadowLayer.superlayer != nil) {
         [self.shadowLayer removeFromSuperlayer];
     }
 }