UI键盘通知
#import "ViewController.h"
@interface ViewController ()
@property (nonatomic,strong) UITextField *tf;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
_tf = [[UITextField alloc]initWithFrame:CGRectMake(10, self.view.bounds.size.height - 40, 300, 30)];
_tf.borderStyle = UITextBorderStyleRoundedRect;
[self.view addSubview:_tf];
/*
通知中心(单例)
通知中心是一对多的，即同一个广播可以被多个收音机接收
代理是一对一
作用：1.用来接收广播和发起广播
2.用通知的名字作为频道
*/
/*
参数一：响应的类
参数二：类中响应的方法
参数三：通知的名字(即频道)
参数四：接收类型 ［注意］nil代表任何类型
*/
//:UIKeyboardWillShowNotification接收键盘将要显示的通知
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyBoardWillShow:) name:UIKeyboardWillShowNotification object:nil];
//UIKeyboardWillHideNotification接收键盘将要隐藏的通知
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyBoardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}
#pragma mark - UIKeyboardWillHideNotification
//键盘将要隐藏
-(void)keyBoardWillHide:(NSNotification *)noti
{
//noti.userInfo是一个字典，大家可以输出来看看字典里面包含了什么
//NSLog(@"%@",noti.userInfo);
//获得弹下去后的坐标[注意是弹下后的]
CGRect keyBoardEndFrame = [[noti.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
//NSLog(@"--%@",NSStringFromCGRect(keyBoardEndFrame));
[UIView animateWithDuration:2 animations:^{
//改变文本框的位置，让它跟着键盘一起弹起来
CGRect tfRext = _tf.frame;
tfRext.origin.y = keyBoardEndFrame.origin.y-_tf.bounds.size.height-10;
_tf.frame = tfRext;
}];
}
#pragma mark - UIKeyBoard notification
//接收到的是通知，所以参数用NSNotification
//键盘将要显示
-(void)keyBoardWillShow:(NSNotification *)noti
{
CGRect keyBoardFrame = [[noti.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
//可以通过以下方法输出CGRect
//NSStringFromCGRect将CGRect转化为字符串的方式获取Frame
//NSLog(@"%@",NSStringFromCGRect(keyBoardFrame));
//获取键盘的动画持续时间
//CGFloat keyBoardDuration = [noti.userInfo[UIKeyboardAnimationDurationUserInfoKey] floatValue];
[UIView animateWithDuration:2 animations:^{
CGRect tfRect = _tf.frame;
tfRect.origin.y = keyBoardFrame.origin.y - _tf.bounds.size.height -10;
_tf.frame = tfRect;
}];
}
#pragma mark - 当手指触碰屏幕任何一地方时被调用
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
//利用结束编辑来隐藏键盘
[self.view endEditing:YES];
}
@end
