i want display list in sharepoint 2013 uses js - sharepoint

Question

Following is my code:
retrieveListItems('https://sustec29-public.sharepoint.com');
function retrieveListItems(siteUrl) {
var clientContext = new SP.ClientContext(siteUrl);
var oList = clientContext.get_web().get_lists().getByTitle('Announcements');
var camlQuery = new SP.CamlQuery();
camlQuery.set_viewXml(
'<View><Query><Where><Geq><FieldRef Name=\'ID\'/>' +
'<Value Type=\'Number\'>1</Value></Geq></Where></Query>' +
'<RowLimit>10</RowLimit></View>'
);
this.collListItem = oList.getItems(camlQuery);
clientContext.load(collListItem);
clientContext.executeQueryAsync(
Function.createDelegate(this, this.onQuerySucceeded),
Function.createDelegate(this, this.onQueryFailed)
);
}
function onQuerySucceeded(sender, args) {
var listItemInfo = '';
var listItemEnumerator = collListItem.getEnumerator();
while (listItemEnumerator.moveNext()) {
var oListItem = listItemEnumerator.get_current();
listItemInfo += '\nID: ' + oListItem.get_id() +
'\ngroup: ' + oListItem.get_item('group') +
'\ndisc: ' + oListItem.get_item('disc');
}
$('#message').text(listItemInfo.toString());
}
function onQueryFailed(sender, args) {
alert('Request failed. ' + args.get_message() +
'\n' + args.get_stackTrace());
}
`
but browser views error -
The property or field has not been initialized. It has not been requested or the request has not been executed. It may need to be explicitly requested.
if i write
'\ntitle: ' + oListItem.get_item('title') + '\nbody: ' + oListItem.get_item('body');
and rename field table`s - all ok.
But i want add own field..

Answer 1

Try to add ViewFields section to your caml query:
camlQuery.set_viewXml(
'<View><Query><Where><Geq><FieldRef Name="ID"/>' +
'<Value Type="Number">1</Value></Geq></Where></Query>' +
'<RowLimit>10</RowLimit><ViewFields><FieldRef Name="group" /><FieldRef Name="disk" /></ViewFields></View>'
EDIT:
Another way you can try to achieve this is to add Include string to your load method call:
clientContext.load(collListItem, 'Include(Id, disk, group)');