iOS 键盘自适应评论cell下方

首先判断点击评论按钮事件  和  回复评论事件（同时注册监听键盘出现和隐藏事件）

然后 获取到 所点击cell的坐标
然后 在键盘出来的时候计算所需要调整的高度

  //注册键盘出现NSNotification

    [[NSNotificationCenterdefaultCenter]
addObserver:self

                                             selector:@selector(keyboardWillShow:)

                                                 name:UIKeyboardWillShowNotificationobject:nil];

    //注册键盘隐藏NSNotification

    [[NSNotificationCenterdefaultCenter]
addObserver:self

                                             selector:@selector(keyboardWillHide:)

                                                 name:UIKeyboardWillHideNotificationobject:nil];

   

//cell的坐标

@property (nonatomic,assign)CGRect
rectSelected;

            NSIndexPath * indexPath2 = [NSIndexPathindexPathForItem:index
inSection:0];

            CGRect rectInTableView = [self.tableViewrectForRowAtIndexPath:indexPath2];

            self.rectSelected = [self.tableViewconvertRect:rectInTableViewtoView:[self.tableViewsuperview]];//转化为在self.view
上的坐标

#pragma mark

#pragma mark keyboardWillShow

- (void)keyboardWillShow:(NSNotification *)notification

{

    

    if (_KeySwitch) {

        

        return;

    }else{

    

        _KeySwitch =YES;

    }

    

    //[0](null)
@"UIKeyboardFrameBeginUserInfoKey" : NSRect: {{0, 736}, {414, 293.66666666666674}}

    //    [1](null)
@"UIKeyboardCenterEndUserInfoKey" : NSPoint: {207, 589.16666666666663}

    //    [2](null)
@"UIKeyboardBoundsUserInfoKey" : NSRect: {{0, 0}, {414, 293.66666666666674}}

    //    [3](null)
@"UIKeyboardFrameEndUserInfoKey" : NSRect: {{0, 442.33333333333326}, {414, 293.66666666666674}}

    //    [5](null)
@"UIKeyboardCenterBeginUserInfoKey" : NSPoint: {207, 882.83333333333337}

    //    [4](null)
@"UIKeyboardAnimationDurationUserInfoKey" : (double)0.25

    //    [6](null)
@"UIKeyboardAnimationCurveUserInfoKey" : (long)7

    //    [7](null)
@"UIKeyboardIsLocalUserInfoKey" : (int)1

    NSDictionary *userInfo = [notificationuserInfo];

    NSValue* aValue = [userInfoobjectForKey:UIKeyboardFrameEndUserInfoKey];//aValueNSConcreteValue
* NSRect: {{0, 442.33333333333326}, {414, 293.66666666666674}}0x0000000136c0c4b0

    __block CGFloat keyboardHeight = [aValueCGRectValue].size.height;//keyboardHeightCGFloat
293.66666666666674

    CGRect keyboardRect = [aValueCGRectValue];//keyboardRectCGRect
(origin = (x = 0, y = 0), size = (width = 8, height = 0))    keyboardRect
CGRect(origin = (x = 0, y = 442.33333333333326), size = (width = 414, height = 293.66666666666674))

    keyboardRect = [self.viewconvertRect:keyboardRectfromView:nil];////将rect从view中转换到当前视图中，返回在当前视图中的rect

    

    CGFloat keyboardTop = keyboardRect.origin.y;//keyboardTopCGFloat
442.33333333333326

    CGRect newTextViewFrame =self.view.bounds;//newTextViewFrameCGRect
(origin = (x = 0, y = 0), size = (width = 414, height = 442.33333333333326))     键盘上面文字区域的坐标

    newTextViewFrame.size.height = keyboardTop -self.view.bounds.origin.y;//上面文字的坐标 高度

    

    NSValue *animationDurationValue = [userInfoobjectForKey:UIKeyboardAnimationDurationUserInfoKey];//animationDurationNSTimeInterval
4.9406564584124654E-324

    NSTimeInterval animationDuration;

    [animationDurationValue getValue:&animationDuration];

    //history_Y_offset   btn转换成在self.view上的坐标

    CGFloat delta =self.rectSelected.origin.y
+ self.rectSelected.size.height
- ([UIApplication
sharedApplication].keyWindow.bounds.size.height
- keyboardHeight-100);//deltaCGFloat
-54.333333333333258

    

    --------------  计算tableview要偏移的距离   ----------

 

    CGPoint offset =self.tableView.contentOffset;//offsetCGPoint
(x = 3.4540270524485753E-314, y = 2.1232730692355269E-314)   表视图的偏移量

    offset.y += delta;//offsetCGPoint
(x = 0, y = -118.33333333333326)

    if (offset.y <0) {

        offset.y = -64;//offsetCGPoint
(x = 0, y = -64)

    }

    [self.tableViewsetContentOffset:offset
animated:YES];

}

#pragma mark

#pragma mark keyboardWillHide

- (void)keyboardWillHide:(NSNotification *)notification {

    

    

    NSValue *animationDurationValue = [notification.userInfoobjectForKey:UIKeyboardAnimationDurationUserInfoKey];

    NSTimeInterval animationDuration;

    [animationDurationValue getValue:&animationDuration];

    [UIViewanimateWithDuration:animationDurationanimations:^{

        //        [self.chatKeyBoard keyboardDownForComment];

        //        self.chatKeyBoard.placeHolder = nil;

    }];

}