UIView生命周期

//  SKView.m
//  SKProject01
//
//  Created by Code_Hou on 2017/4/6.
//  Copyright © 2017年 侯森魁. All rights reserved.
//

#import "SKView.h"

//使用inline函数
/*
 函数的参数压栈，减少了调用的开销 
 当函数体语句较少(1-5行)，且没有复杂的循环语句，且调用次数较多时，就可以用内联函数。
 http://www.cnblogs.com/pengyingh/articles/2405718.html
 */
static inline void SKLog(SEL _cmd){

    NSLog(@"方法名：%@",NSStringFromSelector(_cmd));

};
@implementation SKView

- (void)removeFromSuperview{
    
    [super removeFromSuperview];
    SKLog(_cmd);

}
- (void)insertSubview:(UIView *)view atIndex:(NSInteger)index{
    [super insertSubview:view atIndex:index];
    SKLog(_cmd);

}
- (void)exchangeSubviewAtIndex:(NSInteger)index1 withSubviewAtIndex:(NSInteger)index2{
    
    [super exchangeSubviewAtIndex:index1 withSubviewAtIndex:index2];
    SKLog(_cmd);

}

- (void)addSubview:(UIView *)view{
    [super addSubview:view];
    SKLog(_cmd);

}
- (void)insertSubview:(UIView *)view belowSubview:(UIView *)siblingSubview{
    
    [super insertSubview:view belowSubview:siblingSubview];
    SKLog(_cmd);

}
- (void)insertSubview:(UIView *)view aboveSubview:(UIView *)siblingSubview{
    [super insertSubview:view aboveSubview:siblingSubview];
    SKLog(_cmd);

}

- (void)bringSubviewToFront:(UIView *)view{
    [super bringSubviewToFront:view];
    SKLog(_cmd);

}
- (void)sendSubviewToBack:(UIView *)view{
    [super sendSubviewToBack:view];
    SKLog(_cmd);

}

- (void)didAddSubview:(UIView *)subview{
    [super didAddSubview:subview];
    SKLog(_cmd);

}
- (void)willRemoveSubview:(UIView *)subview{
    [super willRemoveSubview:subview];
    SKLog(_cmd);

}

/*
 
 先添加到父视图上面
 再添加到UIWindow上面
 最后调用layoutSubviews
 */
- (void)willMoveToSuperview:(nullable UIView *)newSuperview{
    [super willMoveToSuperview:newSuperview];
    NSLog(@"newSuperview =%@",newSuperview);

    NSLog(@"[[UIApplication sharedApplication].delegate window]; =%@",[[UIApplication sharedApplication].delegate window]);

    
    SKLog(_cmd);

}
- (void)didMoveToSuperview{
    [super didMoveToSuperview];
    SKLog(_cmd);

}
- (void)willMoveToWindow:(nullable UIWindow *)newWindow{
    
    
    [super willMoveToWindow:newWindow];
    
    NSLog(@"newWindow =%@",newWindow);
    SKLog(_cmd);

}
- (void)didMoveToWindow{
    [super didMoveToWindow];
    SKLog(_cmd);

}

- (BOOL)isDescendantOfView:(UIView *)view{
    SKLog(_cmd);

   return  [super isDescendantOfView:view];
}// returns YES for self.
- (nullable __kindof UIView *)viewWithTag:(NSInteger)tag{
    
    SKLog(_cmd);

    return [super viewWithTag:tag];
}// recursive search. includes self

// Allows you to perform layout before the drawing cycle happens. -layoutIfNeeded forces layout early
- (void)setNeedsLayout{
    
    [super setNeedsLayout];
    SKLog(_cmd);

}
- (void)layoutIfNeeded{
    [super layoutIfNeeded];
    SKLog(_cmd);

}

- (void)layoutSubviews{
    
    [super layoutSubviews];
    
//    NSLog(@"类：%@ 方法名：%@",NSStringFromClass([self class]),NSStringFromSelector(_cmd));
    SKLog(_cmd);
    NSLog(@"self.window =%@",self.window);

}// override point. cal

// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
//- (void)drawRect:(CGRect)rect {
//    // Drawing code
//    [super drawRect:rect];
//    SKLog(_cmd);
//
//}
//setNeedsDisplay 这个方法一定会调用，属于图形渲染，只有获得了渲染的图形，才能进行后续的View操作
- (void)setNeedsDisplay{
    [super setNeedsDisplay];
    SKLog(_cmd);

}
- (void)setNeedsDisplayInRect:(CGRect)rect{
    [super setNeedsDisplayInRect:rect];
    SKLog(_cmd);

}

@end
控制台日志：
2017-04-09 10:30:34.195 SKViewHierarchy[1510:67633] 方法名：setNeedsDisplay
2017-04-09 10:30:34.196 SKViewHierarchy[1510:67633] newSuperview =<UIScrollView: 0x7fe553840a00; frame = (0 100; 300 400); clipsToBounds = YES; gestureRecognizers = <NSArray: 0x600000049ff0>; layer = <CALayer: 0x60800002be40>; contentOffset: {0, 0}; contentSize: {0, 0}>
2017-04-09 10:30:34.196 SKViewHierarchy[1510:67633] [[UIApplication sharedApplication].delegate window]; =<UIWindow: 0x7fe551d06cc0; frame = (0 0; 375 667); gestureRecognizers = <NSArray: 0x60800004d110>; layer = <UIWindowLayer: 0x60800002b8c0>>
2017-04-09 10:30:34.196 SKViewHierarchy[1510:67633] 方法名：willMoveToSuperview:
2017-04-09 10:30:34.197 SKViewHierarchy[1510:67633] 方法名：didMoveToSuperview
2017-04-09 10:30:34.197 SKViewHierarchy[1510:67633] newWindow =<UIWindow: 0x7fe551d06cc0; frame = (0 0; 375 667); gestureRecognizers = <NSArray: 0x60800004d110>; layer = <UIWindowLayer: 0x60800002b8c0>>
2017-04-09 10:30:34.198 SKViewHierarchy[1510:67633] 方法名：willMoveToWindow:
2017-04-09 10:30:34.199 SKViewHierarchy[1510:67633] 方法名：didMoveToWindow
2017-04-09 10:30:34.276 SKViewHierarchy[1510:67633] 方法名：layoutSubviews
2017-04-09 10:30:34.277 SKViewHierarchy[1510:67633] self.window =<UIWindow: 0x7fe551d06cc0; frame = (0 0; 375 667); autoresize = W+H; gestureRecognizers = <NSArray: 0x60800004d110>; layer = <UIWindowLayer: 0x60800002b8c0>>
2017-04-09 10:30:36.204 SKViewHierarchy[1510:67633] 方法名：setNeedsDisplay

UIView有个属性Window,这就是[[UIApplication sharedApplication].delegate window]，神奇
无论创建多少个View的实例，其window属性，都是[[UIApplication sharedApplication].delegate window]