ios - 为什么 UIButton 不响应触摸？

Question

我看了很多回复，还是想不通。我知道第一行有点奇怪，但这是因为它继承自将标题 View 设置为搜索栏的父类(super class)

searchBar = (UISearchBar *)self.tableView.tableHeaderView;
[[searchBar.subviews objectAtIndex:0] removeFromSuperview];

UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, -100, self.view.frame.size.width, 100)];
label.text = @"AAAA";
[searchBar addSubview:label];

UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[button addTarget:self
           action:@selector(aMethod)
 forControlEvents:UIControlEventTouchDown];
[button setTitle:@"Show View" forState:UIControlStateNormal];
button.frame = CGRectMake(80.0, -60, 160.0, 40.0);

searchBar.exclusiveTouch = NO;
searchBar.userInteractionEnabled = NO;
label.userInteractionEnabled = NO;
button.userInteractionEnabled = YES;
[searchBar insertSubview:button atIndex:3];

Answer 1

userInteractionEnabled 在父 View 上设置为 NO 将级联到所有 subview 。因此，您的 UIButton 实例将显示为无响应，因为 searchBar 已禁用。