 
                     // 注意第一次要减去已经有的高度偏移
                     if appearPostIndex == 0 {
-                        strongSelf.conversationCollectionView.contentOffset.y += keyboardHeightIncrement - strongSelf.moreMessageTypesViewHeightConstraintConstant
+                        strongSelf.conversationCollectionView.contentOffset.y += keyboardHeightIncrement - strongSelf.moreMessageTypesViewDefaultHeight
                     } else {
                         strongSelf.conversationCollectionView.contentOffset.y += keyboardHeightIncrement
                     }

    @IBOutlet weak var messageToolbarBottomConstraint: NSLayoutConstraint!

    @IBOutlet weak var moreMessageTypesViewHeightConstraint: NSLayoutConstraint!
    let moreMessageTypesViewHeightConstraintConstant: CGFloat = 110

    @IBOutlet weak var choosePhotoButton: MessageTypeButton!
    @IBOutlet weak var takePhotoButton: MessageTypeButton!

                        if previousState != .BeginTextInput && previousState != .TextInputing {

                            UIView.animateWithDuration(0.2, delay: 0.0, options: .CurveEaseInOut, animations: { _ in
                                strongSelf.conversationCollectionView.contentOffset.y += strongSelf.moreMessageTypesViewDefaultHeight
                                strongSelf.conversationCollectionView.contentInset.bottom = strongSelf.messageToolbar.frame.height + strongSelf.moreMessageTypesViewDefaultHeight

                                strongSelf.messageToolbarBottomConstraint.constant = strongSelf.moreMessageTypesViewDefaultHeight
                                strongSelf.view.layoutIfNeeded()

                            }, completion: { finished in
