     
     override func tableView(tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
         let btn = UIButton(frame:CGRectMake(0,0,0,44))
-//        btn.backgroundColor = UIColor.blueColor()
         btn.setTitleColor(UIColor.grayColor(), forState: UIControlState.Normal)
         btn.contentHorizontalAlignment = UIControlContentHorizontalAlignment.Left
         btn.titleEdgeInsets = UIEdgeInsetsMake(0, 20, 0, 0)
-//        btn.titleLabel?.textAlignment = NSTextAlignment.Left
+        //        btn.titleLabel?.textAlignment = NSTextAlignment.Left
         btn.titleLabel?.font = UIFont.systemFontOfSize(12)
         if let cat = catList?[section] as? Category {
             btn .setTitle(cat.name, forState: UIControlState.Normal)

        expansionList![sender.tag] = !expansionList![sender.tag]
        tableView.reloadSections(NSIndexSet(index: sender.tag), withRowAnimation: UITableViewRowAnimation.Automatic)
    }
    @IBAction func addCategory(sender: UIButton) {
        let ac = UIAlertController(title: "新建分类名", message: nil, preferredStyle: UIAlertControllerStyle.Alert)
        ac.addTextFieldWithConfigurationHandler { (textField: UITextField) -> Void in

    }
    
    /*
     // Override to support conditional editing of the table view.
     override func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -> Bool {
     // Return false if you do not want the specified item to be editable.
     return true
     }
     */
    
    /*
     // Override to support editing the table view.
     override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
     if editingStyle == .Delete {
     // Delete the row from the data source
     tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
     } else if editingStyle == .Insert {
     // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
     }
     }
     */
    
    /*
     // Override to support rearranging the table view.
     override func tableView(tableView: UITableView, moveRowAtIndexPath fromIndexPath: NSIndexPath, toIndexPath: NSIndexPath) {
     
     }
     */
    
    /*
     // Override to support conditional rearranging of the table view.
     override func tableView(tableView: UITableView, canMoveRowAtIndexPath indexPath: NSIndexPath) -> Bool {
     // Return false if you do not want the item to be re-orderable.
     return true
     }
     */
    
    
    // MARK: - Navigation
