ios中TextField防止被键盘遮挡
1、
已上图举例，弹出键盘不会遮挡TextField输入，（下面横线是通过UIView画的线实现的，不用在意这些细节）
2、
获取键盘高度：可以自行百度下，下面有完整代码
3、
设置TextField的代理，实现代理协议，遵守代理方法
4、
计算偏移量。
首先假设TextField被键盘完全覆盖，进行计算应该偏移量，执行代码，发现效果可行后，关闭键盘时返回，一定不要用偏移量去返回，用偏移量会产生非常严重的问题，怎么解决看详细的代码。
其次假设TextField没被键盘覆盖，经测试发现上面假设不变即可以实现目标，其他状态下也可以实现目标。
5、
详细代码：
// 登录注册界面
==================================
#import <UIKit/UIKit.h>
@interface Register1ViewController : UIViewController
@end
// 登录注册界面
#import "Register1ViewController.h"
#import "ReadMeViewController.h"
@interface Register1ViewController () <UITextFieldDelegate>
@property (weak, nonatomic) IBOutlet UITextField *numberFid; // 手机号码
@property (weak, nonatomic) IBOutlet UITextField *securityCodeFid; // 验证码
@property (weak, nonatomic) IBOutlet UIButton *getsecurityCodeBtn; // 获取验证码
@property (weak, nonatomic) IBOutlet UIImageView *changeImg; // 协议选中
@property (weak, nonatomic) IBOutlet UILabel *readLab; // 点击进入协议详情
@property (weak, nonatomic) IBOutlet UIButton *registerBtn; // 立即登录
@property (assign, nonatomic) BOOL isRead; // 是否同意协议
@property (nonatomic, strong) NSTimer *timer; //验证码倒计时
@end
static NSInteger a = 0;
int offset; //偏移量
int key_height; //键盘高度
@implementation Register1ViewController
- (void)viewDidLoad {
[super viewDidLoad];
//设置按钮背景色
// self.navigationController.navigationBar.hidden = YES;
self.numberFid.delegate = self; // 1.代理
self.securityCodeFid.delegate = self; // 1.代理
_getsecurityCodeBtn.backgroundColor = RGBACOLORTitle;
_registerBtn.backgroundColor = RGBACOLORTitle;
self.title = @"登录";
self.isRead = YES;
self.registerBtn.layer.masksToBounds = YES;
self.registerBtn.layer.cornerRadius = 3;
self.getsecurityCodeBtn.layer.masksToBounds = YES;
self.getsecurityCodeBtn.layer.cornerRadius = 3;
self.tabBarController.tabBar.hidden = YES;
UITapGestureRecognizer *changeTap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(changeClick:)];
[self.changeImg addGestureRecognizer:changeTap];
CALayer * layer = [self.changeImg layer];
layer.borderColor = [[UIColor lightGrayColor] CGColor];
layer.borderWidth = 0.5f;
UITapGestureRecognizer *readTap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(readClick:)];
[self.readLab addGestureRecognizer:readTap];
//增加监听，当键盘出现或改变时收出消息
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification
object:nil];
//增加监听，当键退出时收出消息
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification
object:nil];
}
- (void)viewWillAppear:(BOOL)animated{
a = 0;
self.timer = nil;
}
// 实现代理中的方法
// 实现代理中的方法
- (BOOL)textFieldShouldReturn:(UITextField *)textField {
[textField resignFirstResponder];
return YES;
}
- (void)keyboardWillShow:(NSNotification *)aNotification{
NSDictionary *userInfo = [aNotification userInfo];
NSValue *aValue = [userInfo objectForKey:UIKeyboardFrameEndUserInfoKey];
CGRect keyboardRect = [aValue CGRectValue];
key_height = keyboardRect.size.height;
}
//当键退出时调用
- (void)keyboardWillHide:(NSNotification *)aNotification{
}
/***下面是全屏的一个view, view上有子控件 textField的使用方法***/
- (void)textFieldDidBeginEditing:(UITextField *)textField{
//情形1、当前键盘覆盖了TextField （经调试发现即使没有覆盖本方法也同样适用）
// 最后一个控件的y点位置，最后一个控件的高度，有navigation的话要加64，没有可不加
int lastViewHeight = self.registerBtn.frame.origin.y + 30 + 64; // 获取最后一个控件离底端位置，即所占屏幕高度
int textFieldHeight = textField.frame.origin.y + textField.frame.size.height; // 需要移动的Textfield的底端高度
int superHight = lastViewHeight - ScreenHeight;//超出屏幕部分的距离
int destinationPosition = lastViewHeight - superHight - key_height; // 目标位置高度：最后一个控件减去超出的，减去键盘高度
offset = textFieldHeight - destinationPosition + 20;//目标控件顶端位置减去目标位置高度，期望键盘和Textfield有20的距离
NSTimeInterval animationDuration = 0.30f; // 下面都是动画
[UIView beginAnimations:@"ResizeForKeyboard" context:nil];
[UIView setAnimationDuration:animationDuration];
if(offset > 0) //
self.view.frame = CGRectMake(0.0f, -offset, ScreenWidth, ScreenHeight);//经测试ScreenHeight参数貌似不是非常重要，可以用lastViewHeithgt代替
[UIView commitAnimations];
}
- (void)textFieldDidEndEditing:(UITextField *)textField{
// 30是Textfield的高度
if(offset > 0){
NSTimeInterval animationDuration = 0.30f;
[UIView beginAnimations:@"ResizeForKeyboard" context:nil];
[UIView setAnimationDuration:animationDuration];
// 64 是navigation的高度，如果没有，就写为0
self.view.frame = CGRectMake(0.0f, 64, ScreenWidth, ScreenHeight);//经测试ScreenHeight参数貌似不是非常重要，可以用lastViewHeithgt代替
[UIView commitAnimations];
}
}
// 点击事件
// 获取验证码
- (IBAction)getsecurityCodeAction:(UIButton *)sender {
if (!self.numberFid.text || [self.numberFid.text isEqualToString:@""]) {
// [MBProgressHUD show:@"请补全号码或输入正确号码" icon:nil view:self.view time:3];
[MBProgressHUD showAlertView:@"" andMessage:@"请补全号码或输入正确号码"];
return;
}
self.timer = [NSTimer timerWithTimeInterval:1.0 target:self selector:@selector(timerClick) userInfo:nil repeats:YES];
[self getsecurityCode];
[[NSRunLoop currentRunLoop]addTimer:_timer forMode:NSDefaultRunLoopMode];
[_timer fire];
}
// 立即登录
- (IBAction)registerAction:(UIButton *)sender {
if (self.isRead) {
} failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
}];
}else{
[MBProgressHUD showAlertView:@"" andMessage:@"请阅读并同意《用户协议》"];
}
}
- (void)Register{
}
- (void)getsecurityCode{
}
//协议是否选中
- (void)changeClick:(UITapGestureRecognizer *)sender{
if (_isRead) {
self.changeImg.image = nil;
self.isRead = NO;
}else{
self.changeImg.image = [UIImage imageNamed:@"loginandregist_protocol"];
self.isRead = YES;
}
}
//点击进入协议详情
- (void)readClick:(UITapGestureRecognizer *)sender{
ReadMeViewController *vc = [ReadMeViewController new];
[self.navigationController pushViewController:vc animated:YES];
}
- (void)timerClick{
NSInteger b = 60 - a;
if (b > 0) {
self.getsecurityCodeBtn.titleLabel.text = [NSString stringWithFormat:@"重新发送%ld",b];
[self.getsecurityCodeBtn setTitle:[NSString stringWithFormat:@"重新发送%ld",b] forState:(UIControlStateNormal)];
self.getsecurityCodeBtn.userInteractionEnabled = NO;
a++;
}
if (b == 0) {
[self.getsecurityCodeBtn setTitle:@"获取验证码" forState:(UIControlStateNormal)];
self.getsecurityCodeBtn.userInteractionEnabled = YES;
a = 0;
[_timer invalidate];
}
}
// 将键盘收缩
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
[self.view endEditing:YES];
}
@end
=================================
ps：应该没有什么代码遗漏，自己写了三天才完成的，主要计算那里太坑了，
还有就是：
self.view.frame = CGRectMake(0.0f, 64, ScreenWidth, ScreenHeight);
这个写64或者是0，主要是看有没有navigation。有一点小瑕疵，就是在和键盘位置差不多的时候，会重叠一点，计算应该没问题，不知道为啥会这样。