Data view web part throwing error

Question

Hi I'm using a xslt based dataview webpart the steps i have taken to create a data view webpart is that

1. added a list view webpart on the page
2. Modified the toolbar property to show fulll toolbar
3. open the web page containing above list view webpart in sharepoint desginer and converted it to xslt based webpart (to make further changes in UI)
4. saved the page and previewed in browser

in browser web part was throwing the error while i was able to see it properly in desginer witout any error the error maesseged shown in webpart was:

Unable to display this Web Part. To troubleshoot the problem, open this Web page in a Windows SharePoint Services-compatible HTML editor such as Microsoft Office SharePoint Designer. If the problem persists, contact your Web server administrator.

The error message provided in sharepoint log file was :

05/12/2010 17:56:29.54    w3wp.exe (0x19FC)    0x1E9C    Windows SharePoint Services    Web Parts       89a1    Monitorable    Error while executing web part: System.NullReferenceException: Object reference not set to an instance of an object.
                                                                                                                                   at Microsoft.SharePoint.WebPartPages.DataFormWebPart.ResolveParameterValuesToXsl(ArgumentClassWrapper argList)
                                                                                                                                   at Microsoft.SharePoint.WebPartPages.DataFormWebPart.PrepareAndPerformTransform()
05/12/2010 17:56:29.62    w3wp.exe (0x19FC)    0x1E9C    Windows SharePoint Services    Web Controls    88wy    Medium         SPDataSourceView.ExecuteSelect() - selectArguments: IsEmpty=True, MaximumRows=0, RetrieveTotalRowCount=False, SortExpression=, StartRowIndex=0, TotalRowCount=-1
05/12/2010 17:56:29.62    w3wp.exe (0x19FC)    0x1E9C    Windows SharePoint Services    Web Controls    88x2    Medium         SPDataSourceView.ExecuteSelect() - formattedQuery = <Where><Eq><FieldRef Name="Featured"/><Value Type="Boolean">1</Value></Eq></Where>
05/12/2010 17:56:29.64    w3wp.exe (0x19FC)    0x1E9C    Windows SharePoint Services    Web Parts       89a1    Monitorable    Error while executing web part: System.NullReferenceException: Object reference not set to an instance of an object.
                                                                                                                                   at Microsoft.SharePoint.WebPartPages.DataFormWebPart.ResolveParameterValuesToXsl(ArgumentClassWrapper argList)
                                                                                                                                   at Microsoft.SharePoint.WebPartPages.DataFormWebPart.PrepareAndPerformTransform()

Answer 1

I do believe you would be using a custom master page yes? If so, then this is your answer:

http://www.neilrichards.net/blog/?p=42

I ran into this maybe 10 months ago and spent a week banging my head against the wall before I found the solution. Hopefully you will have better luck!

Answer 2

Hi Ashutosh This is the resoltion in the link.

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It’s simple enough to copy the parameter from the subsite dataview into the masterpage dataview. "WebPartPages:DataFormParameter Name=”WebURL” ParameterKey=”WebURL” PropertyName=”ParameterValues” DefaultValue=”/” "

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But my page does not have this parameter at all.

Can any one help to resolve this issue?