I figured this out a while back and forgot to post the answer. Here's a way to do this that works reliably :
public class SimpleTabPanel extends com.sencha.gxt.widget.core.client.PlainTabPanel
implements TabPanel {
Tab currentActiveTab;
private Map<SimpleTab,TabItemConfig> tabConfigs = new HashMap<SimpleTab,TabItemConfig>();
// a map sorted by priority used to keep the expected tab order
SortedMap<TabData, SimpleTab> tabsConfig = new TreeMap<TabData, SimpleTab>(
new Comparator<TabData>() {
@Override
public int compare(TabData o1, TabData o2) {
return Float.compare(o1.getPriority(), o2.getPriority());
}
});
@Override
public Tab addTab(TabData tabData, String historyToken) {
SimpleTab newTab = createNewTab(tabData);
tabsConfig.put(tabData, newTab);
newTab.setTargetHistoryToken(historyToken);
return newTab;
}
private void disableTab(SimpleTab tab, TabData key){
// get and save tab's config.
TabItemConfig tic = getConfig(tab);
tabConfigs.put(tab, tic);
// put new one on tab to disable it.
tic = new TabItemConfig(key.getLabel());
tic.setEnabled(false);
update(tab, tic);
}
public void enableAllTabs(){
for(TabData key : tabsConfig.keySet()){
SimpleTab tab = tabsConfig.get(key);
TabItemConfig tic = tabConfigs.get(tab);
if(tic!=null){
tic.setEnabled(true);
update(tab, tic);
}
}
}
}