Display logs with func logln()

LoggingTextView.swift

// The MIT License (MIT)
//
// Copyright (c) 2015 James Tang (j@jamztang.com)
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

//
// Description:
// LoggingTextView and logln() is a println() replacement to display logs on screen
// Suitable to debug stuffs when the debugger cannot be attached in some situation
//
// Usage:
// Subclass any UITextView to LoggingTextView, and replace your println() to logln()
// Now all logs will go through that text view.
//

import UIKit

let LogNotification = "LogNotification"

public func logln(any: AnyObject) {
    NSNotificationCenter.defaultCenter().postNotificationName(LogNotification, object: any, userInfo: nil)
    println(any)
}

public class LoggingTextView: UITextView {

    override public func awakeFromNib() {
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "logNotification:", name: LogNotification, object: nil)
    }

    func logNotification(notification: NSNotification) {

        if let object: AnyObject = notification.object {
            self.text = "\(self.text)\n\(object)"
        }
    }
    
    deinit {
        NSNotificationCenter.defaultCenter().removeObserver(self)
    }

}