title: How to get value of a NSTextField which is created programmatically in Xamarin MacOS?
body: <p>I get "Object reference not set to an instance of an object" error while trying to print the "StringValue" value of my Texfield created programmatically?</p>
  
  <pre><code>NSTextField[] t = new NSTextField[1];
  
  public override void ViewDidLoad()
  {
   base.ViewDidLoad();
  
   t[0] = new NSTextField();
   t[0].Frame = new CoreGraphics.CGRect(20, 1, 200, 20);
   t[0].Tag = 0;
   t[0].Identifier = "0";
   t[0].StringValue = "yahoo";
   t[0].Bordered = true;
   t[0].Changed += new EventHandler(testt);
   this.myNSBox.AddSubview(t[0]);
  }
  
  public void testt(Object sender, EventArgs e) 
  {
   NSTextField check = sender as NSTextField;
   //var check = sender as NSTextField; this is also not working
   Console.WriteLine(check.StringValue);
  }
  </code></pre>
  
  <p>System.NullReferenceException: Object reference not set to an instance of an object
  at myProject.ViewController.testt (System.Object sender, System.EventArgs e) [0x00008] in
  /path to my folder /ViewController.cs:125
  at AppKit.NSTextField+_NSTextFieldDelegate.Changed (Foundation.NSNotification notification) [0x00011] in /Library/Frameworks/Xamarin.Mac.framework/Versions/6.10.0.17/src/Xamarin.Mac/NSTextField.g.cs:1093
  at at (wrapper managed-to-native) AppKit.NSApplication.NSApplicationMain(int,string[])
  at AppKit.NSApplication.Main (System.String[] args) [0x00040] in /Library/Frameworks/Xamarin.Mac.framework/Versions/6.10.0.17/src/Xamarin.Mac/AppKit/NSApplication.cs:100
  at myProject.MainClass.Main (System.String[] args) [0x00007] in
  /path to my folder /Main.cs:57</p>