拜托，你能纠正我的代码，所以我有一个简单的应用程序示例，文本字段在键盘结束时会向上移动吗？
的代码实现它但我不知道他们的意思是“活动字段存储在自定义变量中（在此示例中称为activeField）”并且我可能做了其他错误。在viewWillAppear中使用registerForKeyboardNotifications是否可以？
我知道这个问题有一些线索，但我是新手，我很难理解它们。我不想只是学习如何，但为什么，这就是为什么我不想使用github其他建议等的现成解决方案。
我的代码atm：
·H：
#import <UIKit/UIKit.h>
@interface VNViewController : UIViewController<UIScrollViewDelegate, UITextFieldDelegate>
@property (weak, nonatomic) IBOutlet UITextField *texticek;
@property (strong, nonatomic) IBOutlet UIScrollView *scrollView;
@end
的.m：
#import "VNViewController.h"
@interface VNViewController ()
@end
@implementation VNViewController
@synthesize scrollView;
@synthesize texticek;
- (void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self registerForKeyboardNotifications];
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
// Call this method somewhere in your view controller setup code.
- (void)registerForKeyboardNotifications
{
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWasShown:)
name:UIKeyboardDidShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWillBeHidden:)
name:UIKeyboardWillHideNotification object:nil];
}
// Called when the UIKeyboardDidShowNotification is sent.
- (void)keyboardWasShown:(NSNotification*)aNotification
{
NSDictionary* info = [aNotification userInfo];
CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
scrollView.contentInset = contentInsets;
scrollView.scrollIndicatorInsets = contentInsets;
// If active text field is hidden by keyboard, scroll it so it's visible
// Your app might not need or want this behavior.
CGRect aRect = self.view.frame;
aRect.size.height -= kbSize.height;
if (!CGRectContainsPoint(aRect, activeField.frame.origin) ) {
[self.scrollView scrollRectToVisible:activeField.frame animated:YES];
}
}
// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
UIEdgeInsets contentInsets = UIEdgeInsetsZero;
scrollView.contentInset = contentInsets;
scrollView.scrollIndicatorInsets = contentInsets;
}
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
activeField = textField;
}
- (void)textFieldDidEndEditing:(UITextField *)textField
{
activeField = nil;
}
@end
答案 0 :(得分：31)
单击它时向上移动文本字段，请使用下面的代码。它只需要你的卷轴出口
- (void)textFieldDidBeginEditing:(UITextField *)textField {
self.scroll.contentOffset = CGPointMake(0, textField.frame.origin.y);
}
您可以通过减去y位置值（textfield.frame.origin.y - 某个值）来更改应显示的文本字段的位置
如果您想为滚动设置动画，可以这样做：
CGPoint newOffset = CGPointMake(0, textField.frame.origin.y-40);
[self.scroll setContentOffset: newOffset animated: YES];
答案 1 :(得分：10)
在ViewDidLoad中，注册通知：
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWasShown:)
name:UIKeyboardDidShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWillBeHidden:)
name:UIKeyboardWillHideNotification object:nil];
添加以下观察者方法，当键盘出现时自动滚动。
- (void)keyboardWasShown:(NSNotification*)notification
{
NSDictionary *info = [notification userInfo];
CGRect keyboardRect = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
keyboardRect = [self.view convertRect:keyboardRect fromView:nil];
UIEdgeInsets contentInset = self.scrollView.contentInset;
contentInset.bottom = keyboardRect.size.height;
self.scrollView.contentInset = contentInset;
}
- (void)keyboardWillBeHidden:(NSNotification*)notification
{
UIEdgeInsets contentInsets = UIEdgeInsetsZero;
self.scrollView.contentInset = contentInsets;
}
#pragma mark TextField Delegates
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
[textField resignFirstResponder];
return YES;
}
答案 2 :(得分：7)
以下是使用Swift的解决方案：
import UIKit
class ExampleViewController: UIViewController, UITextFieldDelegate {
@IBOutlet var scrollView: UIScrollView!
@IBOutlet var textField1: UITextField!
@IBOutlet var textField2: UITextField!
@IBOutlet var textField3: UITextField!
@IBOutlet var textField4: UITextField!
@IBOutlet var textField5: UITextField!
var activeTextField: UITextField!
// MARK: - View
override func viewDidLoad() {
super.viewDidLoad()
self.textField1.delegate = self
self.textField2.delegate = self
self.textField3.delegate = self
self.textField4.delegate = self
self.textField5.delegate = self
}
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
self.registerForKeyboardNotifications()
}
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
self.unregisterFromKeyboardNotifications()
}
// MARK: - Keyboard
// Call this method somewhere in your view controller setup code.
func registerForKeyboardNotifications() {
let center: NSNotificationCenter = NSNotificationCenter.defaultCenter()
center.addObserver(self, selector: "keyboardWasShown:", name: UIKeyboardDidShowNotification, object: nil)
center.addObserver(self, selector: "keyboardWillBeHidden:", name: UIKeyboardWillHideNotification, object: nil)
}
func unregisterFromKeyboardNotifications () {
let center: NSNotificationCenter = NSNotificationCenter.defaultCenter()
center.removeObserver(self, name: UIKeyboardDidShowNotification, object: nil)
center.removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}
// Called when the UIKeyboardDidShowNotification is sent.
func keyboardWasShown (notification: NSNotification) {
let info : NSDictionary = notification.userInfo!
let kbSize = (info.objectForKey(UIKeyboardFrameBeginUserInfoKey)?.CGRectValue() as CGRect!).size
let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
scrollView.contentInset = contentInsets;
scrollView.scrollIndicatorInsets = contentInsets;
// If active text field is hidden by keyboard, scroll it so it's visible
// Your app might not need or want this behavior.
var aRect = self.view.frame
aRect.size.height -= kbSize.height;
if (!CGRectContainsPoint(aRect, self.activeTextField.frame.origin) ) {
self.scrollView.scrollRectToVisible(self.activeTextField.frame, animated: true)
}
}
// Called when the UIKeyboardWillHideNotification is sent
func keyboardWillBeHidden (notification: NSNotification) {
let contentInsets = UIEdgeInsetsZero;
scrollView.contentInset = contentInsets;
scrollView.scrollIndicatorInsets = contentInsets;
}
// MARK: - Text Field
func textFieldDidBeginEditing(textField: UITextField) {
self.activeTextField = textField
}
func textFieldDidEndEditing(textField: UITextField) {
self.activeTextField = nil
}
}
答案 3 :(得分：1)
BSKeyboardControl是一个不错的控件。您需要在视图中提供文本字段。一个实现它的一些委托方法。然后这样做太简单了。带有上一个和下一个按钮的工具栏可用于循环显示的文本字段。以下链接将为您提供有关BSKeyboardControl
的详细说明答案 4 :(得分：1)
改变一个功能：
- (void)keyboardWasShown:(NSNotification*)aNotification
{
NSDictionary* info = [aNotification userInfo];
CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
scrollView.contentInset = contentInsets;
scrollView.scrollIndicatorInsets = contentInsets;
// If active text field is hidden by keyboard, scroll it so it's visible
// Your app might not need or want this behavior.
CGRect aRect = self.view.frame;
aRect.size.height -= kbSize.height;
if (!CGRectContainsPoint(aRect, activeField.frame.origin) ) {
[scrollView setContentOffset:CGPointMake(0,aRect.size.height) animated:YES];
}}
答案 5 :(得分：0)
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
//添加键盘弹出通知
[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(didChangeKeyBoardFrame:) name:UIKeyboardWillChangeFrameNotification object:nil];
}
-(void)viewDidAppear:(BOOL)animated
{
//设置原始contentSize;
[super viewDidAppear:animated];
originalSize = self.mscrollView.contentSize;
}
-(void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
//移除键盘弹出通知
[[NSNotificationCenter defaultCenter]removeObserver:self name:UIKeyboardWillChangeFrameNotification object:nil];
}
-(void)didChangeKeyBoardFrame:(NSNotification *)sender
{
CGRect endRect = [[sender.userInfo objectForKey:@"UIKeyboardFrameEndUserInfoKey"] CGRectValue];
CGPoint mf =[self.view convertPoint:CGPointMake(0,self.name_textfieldDown.frameBottom) fromView:self.mscrollView];
//does the keyboard cover my label
CGFloat distance = mf.y - endRect.origin.y;
// it mean that keyboard will hidden
if(endRect.origin.y == ScreenHeight)
{
// place scrollView back
[UIView animateWithDuration:0.25 animations:^{
self.mscrollView.contentOffset = CGPointMake(0, self.mscrollView.contentSize.height- self.mscrollView.height);
self.mscrollView.contentSize = originalSize;
}];
}
else if (distance>0)
{
//
[UIView animateWithDuration:0.25 animations:^{
CGSize contentSize = originalSize;
contentSize.height +=( endRect.size.height ) ;// I want users can drag scrollView to buttom when keyboard is showing
self.mscrollView.contentSize = contentSize;
self.mscrollView . contentOffset = CGPointMake(0, self.mscrollView.contentOffset.y + distance+20);
}];
}
}
答案 6 :(得分：0)
UITextField * activeField; 对于activeField，您必须在.m文件中声明