場(chǎng)景1:
這是一道筆試題

image.png

場(chǎng)景2:
一個(gè)vc上有 a b c 三個(gè)view，如果vc和a 相互強(qiáng)引用，那么vc在pop后，b c會(huì)不會(huì)走dealloc方法

我的理解是a b c vc都不會(huì)走dealloc方法，但面試官給我的說法是他們打印過，說 b c會(huì)走dealloc方法。
我說不走的理解是：
如果vc都不釋放，self.view也不會(huì)釋放，那么自然也不會(huì)移除self.view上的子控件abc，所以這種場(chǎng)景下vc a b c 都不會(huì)走dealloc方法。
寫代碼驗(yàn)證，我的理解是正確的。

@import UIKit;

@interface ViewControllerA : UIViewController
@end
@interface ViewControllerB : UIViewController
@end
@interface A : UIView

@end
@interface B : UIView

@end
@interface C : UIView
@property(nonatomic) UIViewController *vc;
@end
@implementation ViewControllerA

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [self.navigationController pushViewController:[ViewControllerB new] animated:YES];
}

@end



@implementation ViewControllerB
- (void)dealloc
{
    NSLog(@"---%@---",@"ff");
}
+ (instancetype)new {
    UIStoryboard *sb = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
    return [sb instantiateViewControllerWithIdentifier:@"ViewControllerB"];
}
- (void)viewDidLoad {
    [super viewDidLoad];
    
    [self.view addSubview: [A new]];
    [self.view addSubview: [B new]];
    C *aC = [C new];
    /// 這里view強(qiáng)引用 vc，就會(huì)導(dǎo)致 vc 不釋放
    aC.vc = self;
    [self.view addSubview: aC];

}
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [self.navigationController popViewControllerAnimated:YES];
}
@end
@implementation A

- (void)dealloc
{
    NSLog(@"---%@---",@"A---");
}

@end
@implementation B

- (void)dealloc
{
    NSLog(@"---%@---",@"B---");
}

@end
@implementation C

- (void)dealloc
{
    NSLog(@"---%@---",@"C---");
}

@end