iOS点击空白处或点击背景收起键盘

在viewDidLoad中添加手势

- (void)viewDidLoad{
         [super viewDidLoad];
          UITapGestureRecognizer *tap1 = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(viewTapped:)]; 

          tap1.cancelsTouchesInView = NO;

          [self.view addGestureRecognizer:tap1];

}

然后 实现方法即可

-(void)viewTapped:(UITapGestureRecognizer*)tap1
 {       [self.view endEditing:YES];