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UIP 2.0 Navigation Error
Posted on 2007-11-28
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.ApplicationBlock
Microsoft.ApplicationBlock
System.EventHandler.Invoke
System.Web.UI.Control.OnLo
System.Web.UI.Control.Load
System.Web.UI.Page.Process
Does anyone have an idea as to what would cause this?
Object reference not set to an instance of an object.
Stack Trace:
[NullReferenceException: Object reference not set to an instance of an object.]
Microsoft.ApplicationBlock
Microsoft.ApplicationBlock
System.EventHandler.Invoke
System.Web.UI.Control.OnLo
System.Web.UI.Control.Load
System.Web.UI.Page.Process
Does anyone have an idea as to what would cause this?
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4 Comments
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.ApplicationBl
<state name="WebState" type="Humana.ApplicationBl
<controller name="ReportsController" type="Humana.EnterpriseFR.
<statePersistenceProvider name="WebStatePersistence"
</objectTypes>
<views>
<view name="MenuHome" type="ReportsMenu.aspx" controller="ReportsControl
<view name="LoadActivityReport" type="ActivityReport.aspx"
<view name="LoadErrorReport" type="ErrorReport.aspx" controller="ReportsControl
</views>
<navigationGraph iViewManager="WebFormViewM
<node view="LoadActivityReport">
<navigateTo navigateValue="Redisplay" view="LoadActivityReport" />
<navigateTo navigateValue="Exit" view="MenuHome" />
</node>
</navigationGraph>
<navigationGraph iViewManager="WebFormViewM
<node view="LoadErrorReport">
<navigateTo navigateValue="Exit" view="MenuHome" />
<navigateTo navigateValue="Redisplay" view="LoadErrorReport" />
</node>
</navigationGraph>
</uipConfiguration>
Thanks!
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.ApplicationBl
<state name="WebState" type="Humana.ApplicationBl
<controller name="ReportsController" type="Humana.EnterpriseFR.
<statePersistenceProvider name="WebStatePersistence"
</objectTypes>
<views>
<view name="MenuHome" type="ReportsMenu.aspx" controller="ReportsControl
<view name="LoadActivityReport" type="ActivityReport.aspx"
<view name="LoadErrorReport" type="ErrorReport.aspx" controller="ReportsControl
</views>
<navigationGraph iViewManager="WebFormViewM
<node view="LoadActivityReport">
<navigateTo navigateValue="Redisplay" view="LoadActivityReport" />
<navigateTo navigateValue="Exit" view="MenuHome" />
</node>
</navigationGraph>
<navigationGraph iViewManager="WebFormViewM
<node view="LoadErrorReport">
<navigateTo navigateValue="Exit" view="MenuHome" />
<navigateTo navigateValue="Redisplay" view="LoadErrorReport" />
</node>
</navigationGraph>
</uipConfiguration>
Thanks!
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
}
}
Also, check if the NavigateTo is not null:
public void NavigateBreadCrumb(string NavigateTo)
{
if (NavigateTo != null)
Navigate(NavigateTo);
else
{
// show some error message here
}
}
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.
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.
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