#import "ViewController.h"#import "UIView+FrameExtension.h" // 可以自己寫，以后用著方便#define kDeviceHeight [UIScreen mainScreen].bounds.size.height@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {[super viewDidLoad];// 設置視圖的背景色self.view.backgroundColor = [UIColor lightGrayColor];// 添加第一個文本框 假定位置UITextField *firstField = [[UITextField alloc]initWithFrame:CGRectMake(50, 300, 200, 40)];firstField.backgroundColor = [UIColor whiteColor];[self.view addSubview:firstField];// 添加第一個文本框UITextField *secondField = [[UITextField alloc]initWithFrame:CGRectMake(firstField.x, firstField.bottom + 50, firstField.width , firstField.height)];[self.view addSubview:secondField];secondField.backgroundColor = [UIColor whiteColor];// 注冊鍵盤顯示的通知[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(showKeyboard:) name:UIKeyboardWillShowNotification object:nil];// 注冊鍵盤隱藏的通知[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(hideKeyboard: ) name:UIKeyboardWillHideNotification object:nil];}// 鍵盤彈出時執行這個方法，-(void)showKeyboard:(NSNotification *)notification{// 定義一個文本框，指向正在編輯的文本框，也就是彈出鍵盤的文本框UITextField *txtField;// 今次遍歷當前視圖的所有子視圖， subViews數組保存的是當前視圖所有的子視圖for (UIView *subView in self.view.subviews) {// 如果這個子視圖是一個文本框的話，isKindOfClass方法可以判斷某個變量是不是某個類型的變量if ([subView isKindOfClass:[UITextField class]]) {// 先把這個子視圖轉化為文本框UITextField *tempField = (UITextField *)subView;// 再判斷這個文本框是不是正在編輯if (tempField.isEditing ) {// 如果這個文本框正在編輯，就是我要找的文本框，中斷循環txtField = tempField;break;}}}NSLog(@"%@", notification);// 獲取通知的userInfo屬性NSDictionary *userInfoDict = notification.userInfo;// 通過鍵盤通知的userInfo屬性獲取鍵盤的boundsNSValue *value = [userInfoDict objectForKey:UIKeyboardBoundsUserInfoKey];// 鍵盤的大小CGSize keyboardSize = [value CGRectValue].size;// 鍵盤高度CGFloat keyboardHeight = keyboardSize.height;CGFloat offset = kDeviceHeight - keyboardHeight - txtField.bottom ;if (offset < 0 ) { //這種情況下需要上移offset = offset - 10 ; //保存上移的高度[UIView animateWithDuration:0.5 animations:^{self.view.transform = CGAffineTransformMakeTranslation(0, offset );}];}}-(void)hideKeyboard:(NSNotification *)notification{[UIView animateWithDuration:2 animations:^{self.view.transform = CGAffineTransformIdentity;}];}// 點擊屏幕空白時隱藏鍵盤-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{[self.view endEditing:YES];}@end