1 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillChangeFrame:) name:UIKeyboardWillChangeFrameNotification object:nil];
2
3 - (void)dealloc
4 {
5 [[NSNotificationCenter defaultCenter] removeObserver:self];
6
7 self.topic.top_cmt = self.savedTopCmt;
8 self.topic.cellHeight = 0;
9 }
10
11 - (void)keyboardWillChangeFrame:(NSNotification *)note
12 {
13 // 修改约束
14 CGFloat keyboardY = [note.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue].origin.y;
15 CGFloat screenH = [UIScreen mainScreen].bounds.size.height;
16 self.bottomMargin.constant = screenH - keyboardY;
17
18 // 执行动画
19 CGFloat duration = [note.userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue];
20 [UIView animateWithDuration:duration animations:^{
21 [self.view layoutIfNeeded];
22 }];
23 }
