iOS開發之UIView與UIViewController的生命周期總結

iOS開發中，建立View常見的兩種方式一個是純代碼，一個是借助于XIB；建立ViewController常見的也有兩種方式一個是純代碼，一個是借助于StoryBoard。

通過交流我發現很多童鞋對這些概念都很模糊，于是通過實驗寫一篇部落格供參考。

重寫View的如下方法

@implementation YFView

-(instancetype)init{
    
    self = [super init];
    
    NSLog(@"%s", __func__);
    
    return self;
}

-(instancetype)initWithFrame:(CGRect)frame{
    
    self = [super initWithFrame:(CGRect)frame];
    
    NSLog(@"%s", __func__);
    
    return self;
    
}

-(instancetype)initWithCoder:(NSCoder *)aDecoder{
    
    self = [super initWithCoder:aDecoder];
    
    NSLog(@"%s", __func__);
    
    return self;
    
}

-(void)awakeFromNib{
    
    [super awakeFromNib];
    
    NSLog(@"%s", __func__);
}


-(void)layoutSubviews{
    
    NSLog(@"%s", __func__);
    
}

@end
           

重寫ViewController的如下方法

@implementation YFViewController

-(void)loadView{
    
    NSLog(@"%s", __func__);
    
    [super loadView];
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    NSLog(@"%s", __func__);
    
    self.view.backgroundColor = [UIColor redColor];
}


-(void)viewDidAppear:(BOOL)animated{
    
    NSLog(@"%s", __func__);
    
    [super viewDidAppear:animated];
    
    
}

-(instancetype)init{
    
    self = [super init];
    
    NSLog(@"%s", __func__);
    
    return self;
}

-(instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{
    
    self = [super initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil];
    
    NSLog(@"%s", __func__);
    
    return self;
    
}

-(instancetype)initWithCoder:(NSCoder *)aDecoder{
    
    self = [super initWithCoder:aDecoder];
    
    NSLog(@"%s", __func__);
    
    return self;
    
}

-(void)awakeFromNib{
    
    NSLog(@"%s", __func__);
    
    [super awakeFromNib];
}

@end
           

結論總結

1. 如果控制器是直接通過代碼建立出來的，并且調用方法為[[YFViewController alloc]init]建立VC的生命周期為：

-[YFViewController initWithNibName:bundle:]
-[YFViewController init]
-[YFViewController loadView]
-[YFViewController viewDidLoad]
-[YFViewController viewDidAppear:]
           

1. 如果建立控制器時勾選了XIB，那麼調用方法為[[YFViewController alloc]init]建立VC時的生命周期為：

-[YFViewController initWithNibName:bundle:] 
-[YFViewController init]
-[YFViewController loadView]
-[YFViewController viewDidLoad]
-[YFViewController viewDidAppear:]
           

1. 如果是通過SB建立控制器，那麼VC的生命周期為：

-[ViewController initWithCoder:]
-[ViewController awakeFromNib]
-[ViewController loadView]
-[ViewController viewDidLoad]
-[ViewController viewDidAppear:]
           

1. 如果純代碼建立UIView，調用方式為YFView *yfView = [[YFView alloc]init];那麼它的生命周期為：

-[YFView initWithFrame:]
-[YFView init]
-[YFView layoutSubviews]
           

1. 如果純代碼建立UIView，調用方式為YFView *yfView = [[YFView alloc]initWithFrame:[UIScreen mainScreen].bounds];那麼它的生命周期為：

-[YFView initWithFrame:]
-[YFView layoutSubviews]
           

1. 如果通過XIB建立UIView，調用方式為NSArray *array = [[NSBundle mainBundle]loadNibNamed:@"YFView" owner:nil options:nil];[array lastObject];那麼它的生命周期為：

-[YFView initWithCoder:]
-[YFView awakeFromNib]
-[YFView layoutSubviews]