iOS关闭键盘容易实现(objc/swift)

Objective-C 代码实例方式一

[[[UIApplication sharedApplication] keyWindow] endEditing:YES];

如果一个view上有许多TextField，可以直接

[self.view endEditing:YES];

Objective-C 代码实例方式二

[[self findFirstResponderBeneathView:self] resignFirstResponder];

[[self findFirstResponderBeneathView:self]  becomeFirstResponder];//打开键盘
- (UIView*)findFirstResponderBeneathView:(UIView*)view {
    // Search recursively for first responder
    for ( UIView *childView in view.subviews ) {
        if ( [childView respondsToSelector:@selector(isFirstResponder)] && [childView isFirstResponder] ) 
            return childView;
        UIView *result = [self findFirstResponderBeneathView:childView];
        if ( result ) 
            return result;
    }
    return nil;
}

Swift方式一

UIApplication.sharedApplication().keyWindow?.endEditing(true)

Swift方式二

func findFirstResponderBeneathView(view: UIView) -> () {
        for childView in view.subviews {
            let isChildFirstResponder = childView.isFirstResponder()
            let isChildResponderSelector = childView.respondsToSelector("isFirstResponder")
            if isChildFirstResponder && isChildResponderSelector {
                childView.resignFirstResponder()
            }
            self.findFirstResponderBeneathView(childView as! UIView)
        }
    }