这将非常有效。滚动视图可以根据文本字段位置自动调整。我相信你会感觉很好

static const CGFloat KEYBOARD_ANIMATION_DURATION = 0.25;
static const CGFloat MINIMUM_SCROLL_FRACTION = 0.2;
static const CGFloat MAXIMUM_SCROLL_FRACTION = 0.8;
static const CGFloat PORTRAIT_KEYBOARD_HEIGHT = 216;
static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 162;
@interface LoginVC ()
{
  CGFloat animatedDistance;
   CGRect viewFrameKey;
}

 //In ViewDidLoad
   viewFrameKey=self.view.frame;



- (void)textFieldDidBeginEditing:(UITextField *)textField
{
CGRect textFieldRect =
[self.view.window convertRect:textField.bounds fromView:textField];
CGRect viewRect =
[self.view.window convertRect:self.view.bounds fromView:self.view];
CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
CGFloat numerator =
midline - viewRect.origin.y
- MINIMUM_SCROLL_FRACTION * viewRect.size.height;
CGFloat denominator =
(MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)
* viewRect.size.height;
CGFloat heightFraction = numerator / denominator;
if (heightFraction < 0.0)
{
    heightFraction = 0.0;
}
else if (heightFraction > 1.0)
{
    heightFraction = 1.0;
}
UIInterfaceOrientation orientation =
[[UIApplication sharedApplication] statusBarOrientation];
if (orientation == UIInterfaceOrientationPortrait ||
    orientation == UIInterfaceOrientationPortraitUpsideDown)
{
    animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT * heightFraction);
}
else
{
    animatedDistance = floor(LANDSCAPE_KEYBOARD_HEIGHT * heightFraction);
}
CGRect viewFrame = self.view.frame;
viewFrame.origin.y -= animatedDistance;

[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

[self.view setFrame:viewFrame];

[UIView commitAnimations];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];
[self.view setFrame:viewFrameKey];
[UIView commitAnimations];
}

在更改文本字段或编辑其内容时，我遇到了重新设置为默认主视图的问题（例如，电话文本字段和添加“-”符号，视图返回覆盖文本字段）我最终通过使用自动布局和更改约束常量（而不是通知代理函数中的帧大小或位置）来克服这一问题，如下所示：

另外，我并没有使用滚动视图，只是简单地向上移动视图，但它的工作原理应该类似

func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
    if !keyboardIsShown{
        self.infoViewTopConstraint.constant -= keyboardSize.height
        self.infoViewBottomConstraint.constant += keyboardSize.height
        self.view.setNeedsLayout()
        self.view.layoutIfNeeded()
        keyboardIsShown = true
    }
}

func keyboardWillHide(notification: NSNotification) {
if keyboardIsShown {
    self.infoViewTopConstraint.constant += keyboardSize.height
    self.infoViewBottomConstraint.constant -= keyboardSize.height
    self.view.setNeedsLayout()
    self.view.layoutIfNeeded()
    keyboardIsShown = false
}

在（BOOL）textFieldShouldBeginEditing:（UITextField*）textField中

if (textField.frame.origin.y > self.view.frame.size.height - 216)
    {
        if (screenHeight>500)
            scrollView.contentSize = CGSizeMake(0.0, scrollView.contentSize.height + 100);
        else
            scrollView.contentSize = CGSizeMake(0.0, scrollView.contentSize.height + 216);
        CGPoint scrollPoint = CGPointMake(0.0,(textField.frame.origin.y - (self.view.frame.size.height - 216 - textField.frame.size.height - 20)));
        [scrollView setContentOffset:scrollPoint animated:YES];
    }
    [scrollView setScrollEnabled:YES];

辞职时，你需要写以下代码

scrollView.contentSize = CGSizeMake(0.0, 640);
CGPoint scrollPoint = CGPointMake(0.0,0.0);
[scrollView setContentOffset:scrollPoint animated:YES]; 

扩展UIViewController的简单解决方案

https://github.com/damienromito/VisibleFormViewController

它不需要滚动视图就可以移动视图框架。您可以更改viewcontroller视图的框架，以便整个视图向上移动到足以将firstresponser文本字段置于键盘上方。当我遇到这个问题时，我创建了一个UIViewController的子类来实现这一点。它观察键盘是否会出现通知，并找到第一个响应者子视图，并且（如果需要）它向上动画主视图，以使第一个响应器位于键盘上方。当键盘隐藏时，它会将视图设置回原来的位置。

要使用此子类，请将自定义视图控制器设置为GMKeyboardVC的子类，并继承此功能（只需确保如果实现viewWillAppear和viewWillDisappear，它们必须调用super）。这个班在github上。

RPDP的代码成功地将文本字段移出键盘。但是当你在使用和关闭键盘后滚动到顶部时，顶部已经从视图中向上滚动。模拟器和设备都是如此。要读取该视图顶部的内容，必须重新加载该视图。

他下面的代码难道不应该使视图降低吗？

else
{
    // revert back to the normal state.
    rect.origin.y += kOFFSET_FOR_KEYBOARD;
    rect.size.height -= kOFFSET_FOR_KEYBOARD;
}