SmartGWT and DataSources

[J-Pro]

Good afternoon, dear SmartGWT developers!

I have a fundamental(for me and my project) question. It's like "Am I behaving right or wrong?"

Every time when I look in SmartGWT showcase examples concerning grids, I see this:

DataSource dataSource = someDS.getInstance();
listGrid.setDataSource(dataSource);

I know that almost everywhere in your examples you use XMLs as the datasources. And I understand how do you do it.

In my project I make calls to the server-side using RemoteServiceServlet class and AsyncCallback. And therefore in method onSuccess of AsyncCallback I use recieved result object to change my front-end correspondingly.
For example, I want to get list of objects using a stored procedure and update my ListGrid. Here is the code for it:

ObjectsGetterServiceAsync objectsGetterService = GWT.create(ObjectsGetterService.class);

final ListGrid listGrid = new ListGrid();  
listGrid.setShowAllRecords(true);
listGrid.setAlternateRecordStyles(true);

ListGridField objectNameField = new ListGridField("name", "Name", 200);  
ListGridField objectTypeField = new ListGridField("type", "Type", 200);  
ListGridField objectValueField = new ListGridField("value", "Value", 150);
ListGridField objectdescriptionField = new ListGridField("desrc", "Description", 500);

listGrid.setFields(new ListGridField[] {objectNameField, objectTypeField, objectValueField, objectdescriptionField});        
listGrid.setCanResizeFields(true);


AsyncCallback<List<MyObject>> callback = new AsyncCallback<List<MyObject>>()
{
    @Override
    public void onSuccess(List<MyObject> result)
    {
        if((result != null) && (result.size() > 0))
        {
            MyObjectRecord [] records = new MyObjectRecord[result.size()];
            int i = 0;
            for(MyObject obj: result)
            {
                MyObjectRecord r = new MyObjectRecord();
                r.setName(obj.getName());
                r.setType(obj.getType());
                r.setValue(obj.getValue());
                r.setDescription(obj.getDescription());
                records[i] = r;
                i++;
            }
        
            listGrid.setData(records);
        }            
        else
            SC.say("There is no objects!");
    }
    
    @Override
    public void onFailure(Throwable caught)
    {
        SC.warn("Getting objects failed!");
    }
};

objectsGetterService.getObjects(callback);

For sure you can imagine that my MyObjectRecord class is something like this:

public class MyObjectRecord extends ListGridRecord
{
    public Integer getName()
    {
        return getAttribute("name");
    }

    public void setName(String name)
    {
        setAttribute("name", name);
    }

    // etc...
}

I feel that something I do here I do wrong, although it all works. I mean the architecture thing. I assume that SmartGWT offers much more efficient way to do it.

I read the SmartGWT_Quick_Start_Guide.pdf and found lot of information about data binding and data sources there, BUT there are different approaches and there is said that I need SmartGWT server for some of them(can't recognize for which exactly).

Therefore considering that I'm using free SmartGWT version, can I use different approach in my task here? Can I use data sources here? How can I use it?
For sure I can make a static xml file on the server and read it from client using setDataSource, but I need to dynamically fill the grid, i.e. after server returns a resultset. Or do I need every time create this xml file from a RemoteServiceServlet and parse it from client somehow? Which approach can I use using free version of SmartGWT?

Thank you very much in advance! Your help in this question would be highly appreciated.

[J-Pro]

Please, help me with this issue, I really want my code to be more effective.

[Isomorphic]

If you hadn't said you read the QuickStart Guide, we would tell you to read the QuickStart Guide.

The most effective approach is to use Pro or above.

If you aren't a professional developer (where it's a no-brainer to purchase at least Pro) the Data Integration chapter of the QuickStart Guide recommends several approaches for different scenarios. GWT-RPC (what you're using) is not one of them.

[J-Pro]

Thank you for your reply.

So as I've understood you correctly, if I wish to continue using Free version, my two only ways are either to use GWT-RPC like I do now, or use hard-coded xmls as datasources, like you do in the showcase, am I right?

The minimum level where I can use DataSources like it's described in the QuickStart guide is the Pro level, right?

[Isomorphic]

Incorrect... and, sorry, but no idea how to help you except to recommend a careful re-read of the QuickStart Guide sections already mentioned. It lays all this out very clearly.