#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;
}];
}
通过获取键盘消息的开始状态、结束状态，以及变化周期，可以计算出具体的Y偏移，从而在相同时间里做相同偏移量。
更多信息请查看IT技术专栏
