                     let checkBoxListItem = item as! CheckBoxListItem
                     
                     if checkBoxListItem.isChecked {
-                        prefixCharacters = "- [x] "
+                        prefixString = "- [x] "
                     } else {
-                        prefixCharacters = "- [ ] "
+                        prefixString = "- [ ] "
                     }
                     
                     numberedItemIndex = 1

                    break
                }
                
                let newCharacters = prefixCharacters + characters
                
                allLineCharacters[lineCharactersIndex] = newCharacters
                
                lineCharactersIndex += 1
            }
            
            
        }
        
        let textAppended = allLineCharacters.joinWithSeparator("\n")
        
        return textAppended
    }

    
    // MARK: - Convert
    
    func appendGlyphsWithText(text: String, textRange: UITextRange) -> String
    {
        // All of the point y in seleted text.
        let selectedPointYArray = CKTextUtil.seletedPointYArrayWithTextView(self, selectedRange: textRange, isContainFirstLine: true, sortByAsc: true)
        
        var allLineString = (text as NSString).componentsSeparatedByString("\n")
        
        var numberedItemIndex = 1
        // move location record current range location of string.
        var moveLocationValue = 0
        
        for (index, lineString) in allLineString.enumerate() {
            let currentPosition = self.positionFromPosition(self.beginningOfDocument, offset: moveLocationValue)
            let currentY = self.caretRectForPosition(currentPosition!).origin.y
            
            if let item = itemFromListItemContainerWithY(currentY) {
                var prefixString: String! = ""
                
                switch item.listType() {
                case .Numbered:
                    prefixString = "\(numberedItemIndex). "
                    numberedItemIndex += 1
                    
                    break
                case .Bulleted:
                    prefixString = "* "
                    
                    numberedItemIndex = 1
                    
