hideKeyboard.m

- (void)viewDidLoad
{
    [super viewDidLoad];

    // 背景をクリックしたら、キーボードを隠す
    UITapGestureRecognizer *gestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(closeKeyboard)];
    gestureRecognizer.cancelsTouchesInView = NO;
    [self.view addGestureRecognizer:gestureRecognizer];
    
}

// キーボードを隠す処理
- (void)closeKeyboard {
    [self.view endEditing: YES];
}