-(void)viewWillAppear:(BOOL)animated
{
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWilHide:) name:UIKeyboardWillHideNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];

}
-(void)viewWillDisappear:(BOOL)animated
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
}

-(void)keyboardWilHide:(NSNotification *)note
{
self.tableview.contentInset = UIEdgeInsetsZero;
}
-(void)keyboardWillShow:(NSNotification *)note
{
CGRect keyBoardRect = [note.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
self.tableview.contentInset = UIEdgeInsetsMake(0, 0, keyBoardRect.size.height, 0);
}