#pragma mark - reg & unreg notification
- (void)regNotification{ [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillChangeFrame:) name:UIKeyboardWillChangeFrameNotification object:nil];}- (void)unregNotification{ [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillChangeFrameNotification object:nil];}#pragma mark - notification handler- (void)keyboardWillChangeFrame:(NSNotification *)notification{ NSDictionary *info = [notification userInfo]; CGFloat duration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] floatValue]; CGRect beginKeyboardRect = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue]; CGRect endKeyboardRect = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue]; CGFloat yOffset = endKeyboardRect.origin.y - beginKeyboardRect.origin.y; CGRect inputFieldRect = self.inputTextField.frame; CGRect moreBtnRect = self.moreInputTypeBtn.frame; inputFieldRect.origin.y += yOffset; moreBtnRect.origin.y += yOffset; [UIView animateWithDuration:duration animations:^{ self.inputTextField.frame = inputFieldRect; self.moreInputTypeBtn.frame = moreBtnRect; }];}
通過擷取鍵盤訊息的開始狀態、結束狀態,以及變化周期,可以計算出具體的Y位移,從而在相同時間裡做相同位移量。