Record cannot be cast to ListGridRecord?

[jay.l.fisher]

I'm trying to populate a client only datasource and show it in a grid. I create it with new DataSource(), setClientOnly(true), create a DataSourceField and setPrimaryKey(true) then addField() and add a few others. I then create a few new Record() objects and use setAttribute() to set the field values and use DataSource.addData(myRecord) to fill the data source. Finally I define a ListGrid and setDataSource() to my new data source. It all seems to work fine except that the grid shows up empty. So I add grid.setAutoFetchData(true) and I get a series of runtime errors telling me that ...

java.lang.ClassCastException: com.smartgwt.client.data.Record cannot be cast to com.smartgwt.client.widgets.grid.ListGridRecord

It seems I have to add ListGridRecords to the data source instead of just Records. If I make that change the data appears. But what if I then want to bind some other type of UI widget to the same data source.

I thought a DataSource just contains Records, not specifically ListGridRecords. What am I misunderstanding?

[CI-CUBE]

In a similar case I had to create TreeNodes in my DS instead of Records. Luckily those TreeNodes worked well both in the TreeGrid as well as in the ListGrid. I used one and the same DS to feed both UI widgets (can be seen in the W-SHOP app, see below)

Ekki

* GWT Rocks! * SmartGWT Rocks Even Harder! * SmartGWT PRO 2.1,
GWT 2.0, Jetty 7.0.0, Eclipse 3.5.1, JRE 1.6.0_16 *
For Evaluation only: MySQL 5.1.41, Connector/J 5.1.10

*** www.EasternGraphics.com/X-4GPL ***

[Isomorphic]

Jay can you indicate what version you were working with and what the full stack trace looked like?

[jay.l.fisher]

SmartClient Version: SC_SNAPSHOT-2010-03-03/Enterprise Deployment (built 2010-03-03)

19:58:49.172 [ERROR] [ipgui] Uncaught exception escaped
java.lang.ClassCastException: com.smartgwt.client.data.Record cannot be cast to com.smartgwt.client.widgets.grid.ListGridRecord
    at com.smartgwt.client.widgets.grid.ListGridRecord.getOrCreateRef(ListGridRecord.java:90)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:157)
    at com.google.gwt.dev.shell.BrowserChannel.reactToMessagesWhileWaitingForReturn(BrowserChannel.java:1713)
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:165)
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:120)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:507)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:264)
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)
    at com.google.gwt.core.client.impl.Impl.apply(Impl.java)
    at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:188)
    at sun.reflect.GeneratedMethodAccessor185.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:157)
    at com.google.gwt.dev.shell.BrowserChannel.reactToMessages(BrowserChannel.java:1668)
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:401)
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:222)
    at java.lang.Thread.run(Thread.java:637)

[Isomorphic]

Jay it looks like you may have hit a bug in a nightly, can you upgrade to the official 2.1 release?

[jay.l.fisher]

I thought I had the official 2.1 release. Can you tell me where to get the official 2.1 release for the EE version?

[Catorcio]

I just experienced the same problem and I verified that the solution proposed works. It's strange in any case that I have to add TreeNodes to the client-only datasource.
I run SmartGWT 2.2

[sanas]

I also have the same problem. What's the solution proposed? I haven't understood.

I work with SmartGWT 2.2, Java 1.6 and GWT 2.0.4, but also I tested with SmartGWT2.1 and It's the same...

This not compile:
ListGridRecord[] records = response.getData();

And this...,
ListGridRecord[] records = (ListGridRecord[]) response.getData();

...throws java.lang.ClassCastException: [Lcom.smartgwt.client.data.Record; cannot be cast to [Lcom.smartgwt.client.widgets.grid.ListGridRecord;

I used "GWT-RPC Datasource template" proposed here: http://forums.smartclient.com/showthread.php?t=4556

Can you help me? Thank you so much.

   @Override
   protected void transformResponse(DSResponse response, DSRequest request, Object data) {
      if (request.getOperationType() != null) {
         ListGridRecord[] records = response.getData();
         switch (request.getOperationType()) {
         case ADD:
            if (request.getAttributeAsBoolean(DO_NOT_PROPAGATE) != null && request.getAttributeAsBoolean(DO_NOT_PROPAGATE).equals(Boolean.TRUE)) {
               response.setStatus(-1);
            } else if (request.getAttributeAsBoolean(DO_NOT_HANDLE) == null || request.getAttributeAsBoolean(DO_NOT_HANDLE).equals(Boolean.FALSE)) {
               response.setStatus(-1);
               executeAdd(records);
            }
            break;
         case FETCH:
            executeFetch();
            break;
         case REMOVE:
            if (request.getAttributeAsBoolean(DO_NOT_HANDLE) == null || request.getAttributeAsBoolean(DO_NOT_HANDLE).equals(Boolean.FALSE)) {
               executeRemove(records);
               response.setStatus(-1);
            }
            break;
         case UPDATE:
            if (request.getAttributeAsBoolean(DO_NOT_HANDLE) == null || request.getAttributeAsBoolean(DO_NOT_HANDLE).equals(Boolean.FALSE)) {
               response.setStatus(-1);
               executeEdit(records, request.getAttributeAsObject(PRE_UPDATE_RECORD));
            }
            break;

         default:
            break;
         }
      }
      super.transformResponse(response, request, data);
   }

[jay.l.fisher]

I'm running into this again myself (SmartClient Version: SC_SNAPSHOT-2010-10-03/EVAL Deployment). I am passing around and modifying a RecordList full of Records, but never explicitly casting them as ListGridRecords. It seems to be happening when I use the RecordList to setData on the grid. But it doesn't happen every time and I can't see what is different.

I've traced it with debug and all of my code executes without error. Then when the ListGrid is drawn this exception is thrown.

16:55:12.659 [ERROR] [ipgui] Uncaught exception escaped
java.lang.ClassCastException: com.smartgwt.client.data.Record cannot be cast to com.smartgwt.client.widgets.grid.ListGridRecord
    at com.smartgwt.client.widgets.grid.ListGridRecord.getOrCreateRef(ListGridRecord.java:92)
    at com.smartgwt.client.widgets.grid.ListGridRecord.getOrCreateRef(ListGridRecord.java:1)
    at sun.reflect.GeneratedMethodAccessor44.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:157)
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:326)
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:207)
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:126)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269)
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)
    at com.google.gwt.core.client.impl.Impl.apply(Impl.java)
    at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:214)
    at sun.reflect.GeneratedMethodAccessor29.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:157)
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:281)
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:531)
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:352)
    at java.lang.Thread.run(Thread.java:680)

[jay.l.fisher]

I'm able to recreate the problem. Here is the sequence of events. I call fetchData on a data source and in the callback I save the response.getDataAsRecordList() into a variable. I then use that variable to setData() on a ListGrid. All is fine until I attempt to add to the RecordList. In my case, I process the results of fetchData() and conditionally add or update the Records in it before I the use it to setData() on the ListGrid.

How should I do that? As it is I'm just creating a Record and adding it to the RecordList. Do I have create a ListGridRecord instead?

[Isomorphic]

Hi Jay,
Yes, if you are working with underlying data objects to apply to a ListGrid, you need to work with ListGridRecord rather than Record objects.
Let us know if you can't get it working
Thanks

[jay.l.fisher]

To start with, on the original DataSource.fetchData() callback, how do I get the response data as a RecordList of ListGridRecords? There are only response.getData() and response.getDataAsRecordList() and both of these return collections of Records, not ListGridRecords? I've tried casting and I get the same error.

[Isomorphic]

You should be able to do this: new ListGridRecord(someRecord.getJsObj());

[jay.l.fisher]

That did it, thanks.

[howardxchen]

Hi, I seem to have some problems trying to cast Record into ListGridRecord.

I have tried this on the following Released Versions of SmartGWT + GWT 2.0.3
- 2.2 (May, 2010)
- 2.4 (Jan, 2011)

This seems to be a client side issue where I am getting the same exception message when I try to do the following:

Record[] codecRecords = response.getData([0].getAttributeAsRecordArray("codecs");

ListGridRecord[] gridRecords = new ListGridRecord[codecRecords.length];
if (codecRecords != null) {
for (int x = 0; x < codecRecords.length; x++) {
	gridRecords[x] = new ListGridRecord(codecRecords[x].getJsObj());	}
}

listGrid.setRecords(gridRecords);

java.lang.ClassCastException: com.smartgwt.client.data.Record cannot be cast to com.smartgwt.client.widgets.grid.ListGridRecord
at com.smartgwt.client.widgets.grid.ListGridRecord.getOrCreateRef(ListGridRecord.java:94)
at sun.reflect.GeneratedMethodAccessor53.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:157)
at com.google.gwt.dev.shell.BrowserChannel.reactToMessagesWhileWaitingForReturn(BrowserChannel.java:1713)

Thank you for your help in advanced.