Xamarin FindViewById returns null

Question

Hi guys I need a little advice. I trying to made an android app using Xamarin so C#. I made two layouts and in each one of them I made tow buttons to navigate between them.I

Answer 1

You are setting Main as the layout for your activity and then in the following lines of code you are asking to find a button named Back at runtime which is not part of this layout. This means the following line will return null:

FindViewById(Resource.Id.BackButton)

Now if you do FindViewById(Resource.Id.BackButton).Click, you will definitely get a System.NullReferenceException.

EDIT:

In view of the comments, here is what you should do to achieve what you are looking for:

Create two different activities (Main1 and Main2). In Main1 you do:

    protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);
        this.SetContentView(Resource.Layout.Main);

        this.FindViewById

(Resource.Id.ForwardButton).Click += this.Forward; } public void Forward(object sender, EventArgs e) { this.StartActivity (typeof(Main2)); }

Then in Main2, you do:

    protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);
        this.SetContentView(Resource.Layout.Main2);

        this.FindViewById

(Resource.Id.BackButton).Click += this.Back; } public void Back(object sender, EventArgs e) { this.StartActivity (typeof(Main)); }