Images in grid are not displayed

[eolith421]

Hello!
I hope someona can tell me what am I doing wrong. I want to create a grid table with a column where I display an Image. If I click on this image an action is performed. I get the data for this grid by a GWT RPC call.
However the images are not displayed in the grid.

This is the code of the grid:

ListGridField diagnosisId = new ListGridField("diagnosisId", "ID", 20);
		ListGridField diagnosisName = new ListGridField("diagnosis", lang.assumedDiagnosis(), 150);
		ListGridField action = new ListGridField("action", lang2.action(),100);
		action.setType(ListGridFieldType.IMAGE);
		
		
		list.setWidth(280);
	    list.setHeight100();
	    list.setShowAllRecords(true);
	    list.setWrapCells(true);
	    list.setFields(diagnosisId, diagnosisName, action);
	    list.addDoubleClickHandler(new DoubleClickHandler() {

			@Override
			public void onDoubleClick(DoubleClickEvent event) {
				System.out.println(list.getSelectedRecord().getAttribute("diagnosisId"));
				
				DiagnosisStackSummary stack = new DiagnosisStackSummary(Integer.parseInt(list.getSelectedRecord().getAttribute("diagnosisId")), 500, 400);
				SmartGwtWindow window = new SmartGwtWindow();
				window.createSmartGwtWindow(520, 450, list.getSelectedRecord().getAttribute("diagnosis"), stack.createDiagnosisStackSummary(), false);
				
			}});
	    
	    service.getDiagnosis(sessionPID, new AsyncCallback<List<ClientDmisSessionDiagnosis>>() {

			@Override
			public void onFailure(Throwable caught) {
				Window.alert("Error: "+caught.getMessage());
			}

			@Override
			public void onSuccess(List<ClientDmisSessionDiagnosis> result) {
				data = new DiagnosisGridListData[result.size()];
				System.out.println("Creating Diagnosis list...");
				for(int i = 0; i<result.size(); i++){
					System.out.println("Diagnosis name: "+result.get(i).getRecord().getName());
					Img deleteIcon = new Img("../components/images/delete16.png");
					deleteIcon.setLayoutAlign(Alignment.CENTER);
					deleteIcon.setTitle("Delete");
					
					final int tempId = result.get(i).getPID();
					deleteIcon.addClickHandler(new ClickHandler(){

						@Override
						public void onClick(ClickEvent event) {
							Window.alert("Trashing diagnosis with ID: "+tempId);
							
						}});
					data[i] = new DiagnosisGridListData(result.get(i).getPID(), result.get(i).getRecord().getName(), deleteIcon);
					list.setData(data);
				}
				
			}
	    	
	    });
	    
	    return list;

And this is by data class:

public class DiagnosisGridListData extends ListGridRecord {
	
	public DiagnosisGridListData(int diagnosisId, String diagnosis, Img img){
		setDiagnosisId(diagnosisId);
		setDaignosis(diagnosis);
		setAction(img);
	}

	private void setAction(Img img) {
		setAttribute("action",img);
	}

	private void setDaignosis(String diagnosis) {
		setAttribute("diagnosis",diagnosis);
	}

	private void setDiagnosisId(int diagnosisId) {
		setAttribute("diagnosisId", diagnosisId);
		
	}
}

Thank you really for your help!!!!!!!!