使用iOS SDK：
我有一个带UITextFields的UIView，可以启动键盘。我需要它能够：
启动键盘后，允许滚动UIScrollView的内容以查看其他文本字段自动“跳转”（通过向上滚动）或缩短
我知道我需要一个UIScrollView。我已经尝试将UIView的类更改为UIScrollView，但仍然无法上下滚动文本框。
我需要UIView和UIScrollView吗？一个在另一个里面吗？
要自动滚动到活动文本字段，需要执行哪些操作？
理想情况下，尽可能多的组件设置将在Interface Builder中完成。我只想编写需要的代码。
注意：我使用的UIView（或UIScrollView）是由一个选项卡（UITabBar）启动的，它需要正常工作。
我正在添加滚动条，只为键盘出现时使用。尽管不需要它，但我觉得它提供了一个更好的界面，例如，用户可以滚动和更改文本框。
当键盘上下移动时，我可以改变UIScrollView的框架大小。我只是在使用：
-(void)textFieldDidBeginEditing:(UITextField *)textField {
//Keyboard becomes visible
scrollView.frame = CGRectMake(scrollView.frame.origin.x,
scrollView.frame.origin.y,
scrollView.frame.size.width,
scrollView.frame.size.height - 215 + 50); // Resize
}
-(void)textFieldDidEndEditing:(UITextField *)textField {
// Keyboard will hide
scrollView.frame = CGRectMake(scrollView.frame.origin.x,
scrollView.frame.origin.y,
scrollView.frame.size.width,
scrollView.frame.size.height + 215 - 50); // Resize
}
然而，这不会自动“向上移动”或将可见区域中的下部文本字段居中，这是我真正想要的。
我对UIScrollView由多个UITextField组成也有很多问题，其中一个或多个在编辑时会被键盘遮挡。
如果UIScrollView滚动不正确，请考虑以下几点。
1） 确保contentSize大于UIScrollView框架大小。理解UIScrollViews的方法是UIScrollView就像一个查看contentSize中定义的内容的窗口。因此，如果要让UIScrollview滚动到任何位置，contentSize必须大于UIScrollview。否则，不需要滚动，因为contentSize中定义的所有内容都已可见。BTW，默认contentSize=CGSizeZero。
2） 既然您已经了解到UIScrollView实际上是一个“内容”窗口，那么确保键盘不会遮挡UIScroll View的查看“窗口”的方法就是调整UIScrollView的大小，这样当键盘出现时，UIScrollView窗口的大小就等于UIScrollviewframe.size.height减去键盘的高度。这将确保您的窗口仅是那个小的可视区域。
3） 这里有一个陷阱：当我第一次实现这一点时，我想我必须获得编辑文本字段的CGRect，并调用UIScrollView的scrollRecToVisible方法。我通过调用scrollRecToVisible方法实现了UITextFieldDelegate方法textFieldDidBeginEditing。这实际上产生了一个奇怪的副作用，即滚动会将UITextField捕捉到位。在很长一段时间里，我都搞不清那是什么。然后我注释了textFieldDidBegginEditingDelegate方法，这一切都奏效了！！(???). 事实证明，我相信UIScrollView实际上隐式地将当前编辑的UITextField带入可视窗口。我对UITextFieldDelegate方法的实现以及随后对scrollRecToVisible的调用是多余的，这是产生奇怪副作用的原因。
因此，当键盘出现时，以下是在UIScrollView中正确滚动UITextField的步骤。
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[super viewDidLoad];
// register for keyboard notifications
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWillShow:)
name:UIKeyboardWillShowNotification
object:self.view.window];
// register for keyboard notifications
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWillHide:)
name:UIKeyboardWillHideNotification
object:self.view.window];
keyboardIsShown = NO;
//make contentSize bigger than your scrollSize (you will need to figure out for your own use case)
CGSize scrollContentSize = CGSizeMake(320, 345);
self.scrollView.contentSize = scrollContentSize;
}
- (void)keyboardWillHide:(NSNotification *)n
{
NSDictionary* userInfo = [n userInfo];
// get the size of the keyboard
CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
// resize the scrollview
CGRect viewFrame = self.scrollView.frame;
// I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
viewFrame.size.height += (keyboardSize.height - kTabBarHeight);
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[self.scrollView setFrame:viewFrame];
[UIView commitAnimations];
keyboardIsShown = NO;
}
- (void)keyboardWillShow:(NSNotification *)n
{
// This is an ivar I'm using to ensure that we do not do the frame size adjustment on the `UIScrollView` if the keyboard is already shown. This can happen if the user, after fixing editing a `UITextField`, scrolls the resized `UIScrollView` to another `UITextField` and attempts to edit the next `UITextField`. If we were to resize the `UIScrollView` again, it would be disastrous. NOTE: The keyboard notification will fire even when the keyboard is already shown.
if (keyboardIsShown) {
return;
}
NSDictionary* userInfo = [n userInfo];
// get the size of the keyboard
CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
// resize the noteView
CGRect viewFrame = self.scrollView.frame;
// I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
viewFrame.size.height -= (keyboardSize.height - kTabBarHeight);
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[self.scrollView setFrame:viewFrame];
[UIView commitAnimations];
keyboardIsShown = YES;
}
在viewDidLoad上注册键盘通知在viewDidUnload中注销键盘nofitions确保contentSize设置为大于UIScrollView at viewDidLoad当有键盘时，缩小UIScrollView当键盘离开时，恢复UIScrollView。使用ivar来检测键盘是否已经显示在屏幕上，因为每次UITextField选项卡时都会发送键盘通知，即使键盘已经存在，以避免在UIScrollView已经缩小时缩小它
需要注意的一点是，当您单击另一个UITextField时，即使键盘已经在屏幕上，UIKeyboardWillShowNotification也会启动。当键盘已经在屏幕上时，我使用ivar来避免调整UIScrollView的大小。当键盘已经存在时，不小心调整UIScrollView的大小将是灾难性的！
希望这段代码能让你们中的一些人省去很多麻烦。
在这里，我找到了处理键盘的最简单的解决方案。
您只需复制粘贴到示例代码下面，然后更改文本字段或任何要向上移动的视图。
步骤-1
只需在控制器中复制粘贴以下两种方法
- (void)registerForKeyboardNotifications
{
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:)
name:UIKeyboardDidShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillBeHidden:)
name:UIKeyboardWillHideNotification object:nil];
}
- (void)deregisterFromKeyboardNotifications
{
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardDidHideNotification object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}
步骤-2
在视图中注册和注销键盘通知WillAppear和viewWillDisappear方法。
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self registerForKeyboardNotifications];
}
- (void)viewWillDisappear:(BOOL)animated
{
[self deregisterFromKeyboardNotifications];
[super viewWillDisappear:animated];
}
步骤-3
灵魂部分来了，只要替换你的文本字段，然后改变高度你想向上移动多少。
- (void)keyboardWasShown:(NSNotification *)notification
{
NSDictionary* info = [notification userInfo];
CGSize currentKeyboardSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
//you need replace your textfield instance here
CGPoint textFieldOrigin = self.tokenForPlaceField.frame.origin;
CGFloat textFieldHeight = self.tokenForPlaceField.frame.size.height;
CGRect visibleRect = self.view.frame;
visibleRect.size.height -= currentKeyboardSize.height;
if (!CGRectContainsPoint(visibleRect, textFieldOrigin))
{
//you can add yor desired height how much you want move keypad up, by replacing "textFieldHeight" below
CGPoint scrollPoint = CGPointMake(0.0, textFieldOrigin.y - visibleRect.size.height + textFieldHeight); //replace textFieldHeight to currentKeyboardSize.height, if you want to move up with more height
[self.scrollView setContentOffset:scrollPoint animated:YES];
}
}
- (void)keyboardWillBeHidden:(NSNotification *)notification
{
[self.scrollView setContentOffset:CGPointZero animated:YES];
}
参考：好吧，请感谢这位分享了这个漂亮的代码片段、干净的解决方案的人。
希望这对外面的人会很有帮助。
斯威夫特4。
您可以使用带有动画的UIKeyBoard轻松上下移动UITextField或UIView
import UIKit
class ViewController: UIViewController, UITextFieldDelegate {
@IBOutlet var textField: UITextField!
@IBOutlet var chatView: UIView!
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChange), name: .UIKeyboardWillChangeFrame, object: nil)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
textField.resignFirstResponder()
}
@objc func keyboardWillChange(notification: NSNotification) {
let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
let curve = notification.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! UInt
let curFrame = (notification.userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
let targetFrame = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
let deltaY = targetFrame.origin.y - curFrame.origin.y
print("deltaY",deltaY)
UIView.animateKeyframes(withDuration: duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
self.chatView.frame.origin.y+=deltaY // Here You Can Change UIView To UITextField
},completion: nil)
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
}
下面是带有文本字段的滚动视图的简单解决方案，不需要任何约束或活动文本字段等。。。
override func viewWillAppear(_ animated: Bool){
super.viewWillAppear(animated)
registerForKeyboardNotifications();
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
deregisterFromKeyboardNotifications();
}
//MARK:- KEYBOARD DELEGATE METHODS
func registerForKeyboardNotifications(){
//Adding notifies on keyboard appearing
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
func deregisterFromKeyboardNotifications(){
//Removing notifies on keyboard appearing
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
func keyboardWasShown(notification: NSNotification){
var info = notification.userInfo!
let keyboardSize = (info[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.size
var contentInset:UIEdgeInsets = self.scrRegister.contentInset
contentInset.bottom = (keyboardSize?.height)!
scrRegister.contentInset = contentInset
}
func keyboardWillBeHidden(notification: NSNotification)
{
var contentInset:UIEdgeInsets = self.scrRegister.contentInset
contentInset.bottom = 0
scrRegister.contentInset = contentInset
}
