I have a master page with that code:
    public string CallbackMethod;
    protected void Page_Load(object sender, EventArgs e)
    {
        CallbackMethod = Page.ClientScript.GetCallbackEventReference(this, "message", 
                         "Dodanie", "context", true);
    }
    /other code here/
then, in the View (which is based on that master page) I need to invoke the CallbackMethod string, but the problem is, the framework firstly renders the View, and then invokes the Page_Load method. As the obvious result, the error appears:  
  the name 'CallbackMethod' does not exist in the current context. 
How do I fix this?