UISearchController 使用中遇到的各種問題

首先初始化，這就不細說了，三個代理都寫上：

    _searchController.searchResultsUpdater = self;
    _searchController.searchBar.delegate = self;
    _searchController.delegate = self;

一、自動彈出鍵盤

以往的寫法：

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    self.searchController.active = true;
}

- (void)didPresentSearchController:(UISearchController *)searchController {
    [self.searchController.searchBar becomeFirstResponder];

}

實現如上的代碼就可以了，但是如果把searchbar寫到導航條上，發現這么寫完全是沒作用的。修改：

- (void)didPresentSearchController:(UISearchController *)searchController {
    [UIView animateWithDuration:0.1 animations:^{} completion:^(BOOL finished) {
        [self.searchController.searchBar becomeFirstResponder];
    }];
}

二、搜索輸入時禁止searchBar上移隱藏導航條

 _searchController.hidesNavigationBarDuringPresentation = NO;

三、修改searchBar取消按鈕的顏色和文字

 [[UIBarButtonItem appearanceWhenContainedInInstancesOfClasses:@[[UISearchBar class]]] setTintColor:[UIColor whiteColor]];
 [[UIBarButtonItem appearanceWhenContainedInInstancesOfClasses:@[[UISearchBar class]]] setTitle:@"取消"];

四、顯示searBar的光標（如果不顯示可以這么設置）

 _searchController.searchBar.tintColor = [UIColor blueberryColor];