常见算法之Hash

简介

收集 Hash 相关的常见算法

查找两个子视图的共同父视图

#import <UIKit/UIKit.h>

@interface UIView (CommonAncestors)

+ (NSArray<UIView *> *)allCommonAncestorsForView:(UIView *)view1 andView:(UIView *)view2;

@end

@implementation UIView (CommonAncestors)

+ (NSArray<UIView *> *)allCommonAncestorsForView:(UIView *)view1 andView:(UIView *)view2 {
    // 获取 view1 的所有父视图
    NSMutableSet<UIView *> *ancestors1 = [NSMutableSet set];
    UIView *current = view1;
    while (current) {
        [ancestors1 addObject:current];
        current = current.superview;
    }

    // 获取 view2 的所有父视图，并找到共同的祖先视图
    NSMutableArray<UIView *> *commonAncestors = [NSMutableArray array];
    current = view2;
    while (current) {
        if ([ancestors1 containsObject:current]) {
            [commonAncestors addObject:current];
        }
        current = current.superview;
    }

    return [commonAncestors copy];
}

@end

// 测试代码
- (void)testAllCommonAncestors {
    // 创建视图层次结构
    UIView *rootView = [[UIView alloc] init];
    UIView *commonParent1 = [[UIView alloc] init];
    UIView *commonParent2 = [[UIView alloc] init];
    UIView *parent1 = [[UIView alloc] init];
    UIView *parent2 = [[UIView alloc] init];
    UIView *child1 = [[UIView alloc] init];
    UIView *child2 = [[UIView alloc] init];

    // 设置视图层次结构
    [rootView addSubview:commonParent1];
    [commonParent1 addSubview:commonParent2];
    [commonParent2 addSubview:parent1];
    [commonParent2 addSubview:parent2];
    [parent1 addSubview:child1];
    [parent2 addSubview:child2];

    // 查找所有共同父视图
    NSArray<UIView *> *commonAncestors = [UIView allCommonAncestorsForView:child1 andView:child2];
    if (commonAncestors.count > 0) {
        for (UIView *ancestor in commonAncestors) {
            NSLog(@"共同父视图: %@", ancestor);
        }
    } else {
        NSLog(@"没有找到共同父视图");
    }
}