iOS TextField inputAccessoryView之隐藏键盘

在iOS里默认键盘弹出后用户点击其他地方是不会让键盘回收的
用户体验非常不好
解决办法

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
             [self.fieldPhone resignFirstResponder];
}

这种解决方案不会给予用户提示，只能让用户去臆测
在体验了众多App 中发现有款App在键盘的右上角加入了一个Button用以隐藏键盘
(具体是哪个App忘记了)

Simulator Screen Shot - iPhone 8 Plus - 2019-04-17 at 11.18.13.png

实现代码

    CGFloat width = 90 ;
    CGFloat height = 36 ;
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, height)];
    UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake([UIScreen mainScreen].bounds.size.width- width, 0, width, height)];
    [btn setTitle:@"隐藏键盘" forState:UIControlStateNormal];
    btn.titleLabel.font = [UIFont systemFontOfSize:16];
    [btn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [view addSubview:btn];
    [btn setBackgroundColor:[UIColor whiteColor]];
    [view setBackgroundColor:[UIColor clearColor]];
    [btn addTarget:self action:@selector(resignFirstResponder) forControlEvents:UIControlEventTouchUpInside];
    self.inputAccessoryView = view;

UITextField中的inputView如果不为nil的话不会弹出系统键盘
inputAccessoryView不为nil则会跟着系统键盘一起弹出