Solved

UIP 2.0 Navigation Error

Posted on 2007-11-28
4
524 Views
Last Modified: 2013-11-07
I am in the process of converting an application from the .net 1.1 framework to .net 2.0 that uses the Microsoft UIP Application block.  This app uses a graph navigator which hasn't changed during conversion.  When I start the app and try to test each of the views, I randomly receive the error:

Object reference not set to an instance of an object.

Stack Trace:
[NullReferenceException: Object reference not set to an instance of an object.]
   Microsoft.ApplicationBlocks.UIProcess.ViewManagerFactory.Create() +166
   Microsoft.ApplicationBlocks.UIProcess.OpenNavigator..ctor(String name, Guid taskId) +45
    System.EventHandler.Invoke(Object sender, EventArgs e) +0
   System.Web.UI.Control.OnLoad(EventArgs e) +99
   System.Web.UI.Control.LoadRecursive() +47
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1061

Does anyone have an idea as to what would cause this?
0
Comment
Question by:sarah_newcom
  • 2
  • 2
4 Comments
 
LVL 55

Expert Comment

by:Jaime Olivares
ID: 20367722
Please post the lines of source code around the error line.
0
 

Author Comment

by:sarah_newcom
ID: 20367835
Sorry about that.
Here is my source code (at least where I think it is breaking):

public void NavigateBreadCrumb(string NavigateTo)
{      
           Navigate(NavigateTo);
}

I've stepped through this code, and the NavigateTo parameter is always populated with the view name that I want to navigate to.

Here is the UIP portion of my config file:
<uipConfiguration enableStateCache="true" allowBackButton="false">
    <objectTypes>
      <iViewManager name="WebFormViewManager" type="Humana.ApplicationBlocks.UIProcess.WebFormViewManager,Humana.ApplicationBlocks.UIProcess,Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
      <state name="WebState" type="Humana.ApplicationBlocks.UIProcess.WebState,Humana.ApplicationBlocks.UIProcess,Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
      <controller name="ReportsController" type="Humana.EnterpriseFR.Reports.Controllers.ReportsController, Humana.EnterpriseFR.Reports, Version=1.0.0.0,Culture=neutral,PublicKeyToken=null" />
      <statePersistenceProvider name="WebStatePersistence" type="Humana.ApplicationBlocks.UIProcess.WebStatePersistence,Humana.ApplicationBlocks.UIProcess, Version=1.0.0.0,Culture=neutral, PublicKeyToken=null" />
    </objectTypes>
    <views>
      <view name="MenuHome" type="ReportsMenu.aspx" controller="ReportsController" />
      <view name="LoadActivityReport" type="ActivityReport.aspx" controller="ReportsController" />
      <view name="LoadErrorReport" type="ErrorReport.aspx" controller="ReportsController" />
    </views>
    <navigationGraph iViewManager="WebFormViewManager" name="ActivityReport" state="WebState" statePersist="WebStatePersistence" startView="LoadActivityReport" cacheExpirationMode="Absolute" cacheExpirationInterval="12:00:00">
      <node view="LoadActivityReport">
        <navigateTo navigateValue="Redisplay" view="LoadActivityReport" />
        <navigateTo navigateValue="Exit" view="MenuHome" />
      </node>
    </navigationGraph>
    <navigationGraph iViewManager="WebFormViewManager" name="ErrorReport" state="WebState" statePersist="WebStatePersistence" startView="LoadErrorReport" cacheExpirationMode="Absolute" cacheExpirationInterval="12:00:00">
      <node view="LoadErrorReport">
        <navigateTo navigateValue="Exit" view="MenuHome" />
        <navigateTo navigateValue="Redisplay" view="LoadErrorReport" />
      </node>
    </navigationGraph>
  </uipConfiguration>

Thanks!

0
 
LVL 55

Accepted Solution

by:
Jaime Olivares earned 500 total points
ID: 20367872
doesn't help so much. are you sure the error is there, of maybe before calling that method?

Also, check if the NavigateTo is not null:

public void NavigateBreadCrumb(string NavigateTo)
{      
        if (NavigateTo != null)
           Navigate(NavigateTo);
        else
        {
                   // show some error message here
          }
}
0
 

Author Comment

by:sarah_newcom
ID: 20368314
Jaime,
You were right, that isn't where the error is located.  When I step through the code it occurs after the navigate statement.  It's erroring out somewhere between the end of the navigate call and the page_load event of the next view.  Not sure why this is happening since it all works without fail with the 1.4 version.
0

Featured Post

MIM Survival Guide for Service Desk Managers

Major incidents can send mastered service desk processes into disorder. Systems and tools produce the data needed to resolve these incidents, but your challenge is getting that information to the right people fast. Check out the Survival Guide and begin bringing order to chaos.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

IP addresses can be stored in a database in any of several ways.  These ways may vary based on the volume of the data.  I was dealing with quite a large amount of data for user authentication purpose, and needed a way to minimize the storage.   …
Recently while returning home from work my wife (another .NET developer) was murmuring something. On further poking she said that she has been assigned a task where she has to serialize and deserialize objects and she is afraid of serialization. Wha…
Attackers love to prey on accounts that have privileges. Reducing privileged accounts and protecting privileged accounts therefore is paramount. Users, groups, and service accounts need to be protected to help protect the entire Active Directory …

679 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question