title: Facebook login, problem with hash key - Flutter , How to generate Facebook Hashkey in flutter?
body: <p><strong>A window appears with the entrance to Facebook and when you click continue to arise an error</strong></p>
  
  <blockquote>
    <p>SERVER_ERROR: [code] 1349195 [message]: the key hash does not match
    any of the saved hashes</p>
  </blockquote>
  
  <pre><code>login() async {
      final facebookLogin = new FacebookLogin();
      final result = await facebookLogin.logInWithReadPermissions(['email']);
      switch (result.status) {
        case FacebookLoginStatus.loggedIn:
          print(result.accessToken.token);
          Navigator.of(context).pushReplacementNamed('/home_screen');
          break;
        case FacebookLoginStatus.cancelledByUser:
          print('CANCELED BY USER');
          break;
        case FacebookLoginStatus.error:
          print(result.errorMessage);
          break;
      }
    }
  </code></pre>