Listgrid grouping performance issue

[weaxler]

1. version smartgwtpro-4.1d_2013-10-14
2. Firefox 24.0

5. Uncaught JavaScript exception [TypeError: _1 is null] in http://127.0.0.1:8888/smartgwttestcanvas/sc/modules/ISC_Grids.js, line 104

6. Ungroup all and scroll down to start "loading" new records. Hereafter, grouping never stops.
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package com._2operate.testcanvas.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.Random;
import com.google.gwt.user.client.ui.RootPanel;
import com.smartgwt.client.types.ListGridFieldType;
import com.smartgwt.client.widgets.events.ScrolledEvent;
import com.smartgwt.client.widgets.events.ScrolledHandler;
import com.smartgwt.client.widgets.grid.ListGrid;
import com.smartgwt.client.widgets.grid.ListGridField;
import com.smartgwt.client.widgets.grid.ListGridRecord;
import com.smartgwt.client.widgets.layout.HLayout;
import com.smartgwt.client.widgets.layout.VLayout;

public class SmartGWTProTestCanvas implements EntryPoint {
ListGrid usersGrid;
int totalNumberOfUsers = 0;

public void onModuleLoad() {
VLayout layout = new VLayout();
layout.setMembersMargin(10);

final HLayout parentCanvas = new HLayout();
parentCanvas.setTop(40);
parentCanvas.setWidth(600);
parentCanvas.setHeight(500);
parentCanvas.setShowEdges(true);
usersGrid = new ListGrid();
usersGrid.setHeight100();
usersGrid.setWidth100();
usersGrid.setAlternateRecordStyles(true);
usersGrid.setShowAllRecords(true);
usersGrid.setIsGroup(true);
usersGrid.setCanGroupBy(true);
usersGrid.addScrolledHandler(new ScrolledHandler() {

public void onScrolled(ScrolledEvent event) {
Integer[] rows = usersGrid.getVisibleRows();
int last = rows[1];
if (last > totalNumberOfUsers) {
addUsers(5);
}
}

});

ListGridField userIdField = new ListGridField("id", "Id");
ListGridField usernameField = new ListGridField("name", "Name");
ListGridField adminField = new ListGridField("isAdmin", "Administrator");
ListGridField roleField = new ListGridField("role", "Role");

usersGrid.setGroupByField("role");
adminField.setType(ListGridFieldType.BOOLEAN);
usersGrid.setFields(new ListGridField[] { userIdField, usernameField, adminField, roleField });


parentCanvas.addMember(usersGrid);
layout.addMember(parentCanvas);
layout.draw();
RootPanel.get("testContainer").add(layout);
addUsers(100);
}

private void addUsers(int numberOfNewUsers) {
totalNumberOfUsers = totalNumberOfUsers + numberOfNewUsers;
ListGridRecord[] data = new ListGridRecord[totalNumberOfUsers];
for (int i = 0; i < numberOfNewUsers; i++) {
ListGridRecord record = new ListGridRecord();
record.setAttribute("id", i);
record.setAttribute("name", "User_" + i);
record.setAttribute("isAdmin", Random.nextBoolean());
record.setAttribute("role", getRole());
data[i] = record;
}
usersGrid.setData(data);
}

private String getRole() {
int roleId = Random.nextInt(3);
String role = "man";
if (roleId == 0){
role = "man";
}
else if (roleId == 1){
role = "woman";
}
else if (roleId == 2){
role = "dog";
}
return role;
}
}

[weaxler]

Hello world..

No clues or feedback at all..?

[Isomorphic]

We investigated this as a possible bug, but it's just a broken test case. You end up with null records in your array, which is fixed by this change:

         ListGridRecord[] data = new ListGridRecord[totalNumberOfUsers];
-        for (int i = 0; i < numberOfNewUsers; i++) {
+        for (int i = 0; i < totalNumberOfUsers; i++) {

We did go ahead and adjust the framework code so it ignores nulls rather than crashes, just so this doesn't look like a framework issue to anyone else.