如何垂直对齐UISearchBar和右侧栏按钮项

Question

我正在开发iOS应用程序。它有搜索栏和右侧栏按钮项（几个按钮）。

这些东西初始化如下：

UISearchController *searchController = [[UISearchController alloc] initWithSearchResultsController:nil];
UISearchBar *searchBar = searchController.searchBar;
[searchBar sizeToFit];
searchBar.placeholder = @"Search";

UIButton *routeButton = [UIButton buttonWithType:UIButtonTypeCustom];
[routeButton setBackgroundImage:[UIImage imageNamed:@"go_route"] forState:UIControlStateNormal];
routeButton.frame = CGRectMake(0., 0., 30., 30.);

UIButton *cancelButton = [UIButton buttonWithType:UIButtonTypeCustom];
[cancelButton setBackgroundImage:[UIImage imageNamed:@"cancel"] forState:UIControlStateNormal];
cancelButton.frame = CGRectMake(0., 0., 30., 30.);

UIBarButtonItem *routeButtonItem = [[UIBarButtonItem alloc] initWithCustomView:routeButton];
UIBarButtonItem *cancelButtonItem = [[UIBarButtonItem alloc] initWithCustomView:cancelButton];

self.navigationItem.rightBarButtonItems = @[cancelButtonItem, routeButtonItem];
self.navigationItem.titleView = searchBar;

从功能上讲，它按预期工作，但看起来有点奇怪：按钮的绘制比搜索栏略高：

我希望按钮稍微低一些，以便与搜索栏垂直对齐。我如何实现它？

P.S。 似乎如果我改变cancelButton.frame = CGRectMake(0., y, 30., 30.);中的y坐标 - 它没有任何效果。

Answer 1

尝试在viewDidAppear中添加您的代码，如下所示，

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];

    // Enter your code

}

您将导航项目居中，如果框架未更新，请尝试

在viewDidAppear中更新其“y”位置，否则请尝试如下设置框架与搜索栏完全相邻，

routeButton.center = CGPointMake(routeButton.center.x, searchBar.center.y);