title: How to change navigation page back button in xamarin forms
body: <p>I am trying to change back arrow image in navigation page. For this in android app i created navigation page renderer and then using method toolbar.SetNavigationIcon and its not working, but when i use toolbar.SetLogo its working fine.</p>
  
  <pre><code>    protected override void OnElementChanged(ElementChangedEventArgs&lt;NavigationPage&gt; e)
      {
  
          base.OnElementChanged(e);
          toolbar.SetNavigationIcon(Resource.Drawable.arrow); 
          toolbar.SetLogo(Resource.Drawable.arrow);
      }
      public override void OnViewAdded(Android.Views.View child)
      {
          base.OnViewAdded(child);
          if (child.GetType() == typeof(Android.Support.V7.Widget.Toolbar))
          {
              toolbar = (Android.Support.V7.Widget.Toolbar)child;
              toolbar.ChildViewAdded += Toolbar_ChildViewAdded;
          }
      }
  </code></pre>
  
  <p>I also tried add image to app:navigationIcon in toolbar.axml, and it shows great in designer
  <a href="https://i.stack.imgur.com/uMmYh.png" rel="nofollow noreferrer">my arrow</a></p>
  
  <p>But, when i starting my app i have the same standart arrow icon
  <a href="https://i.stack.imgur.com/ET5oF.png" rel="nofollow noreferrer">enter image description here</a></p>