JavaScript just running in Edit mode

Question

I have a view form in a list. I want to add a dropdown and populate that dropdown from Another list, so I added a scripteditor in my viewform and added the code below. I can get my code to run when I have the page in edit mode, but not when I open the form.

I've tried to disable the "Minimal download strategy"

I get an errormessage in the browsers debugger when I run the code normally:

Error: Unable to get property 'isNullOrUndefined' of undefined or null reference in sp.js file.

CODE:

<button class="ms-Button ms-Button--hero"> <span class="ms-Button-icon"><i class="ms-Icon ms-Icon--plus"></i></span> <span class="ms-Button-label">Add Role</span> <span class="ms-Button-description">Adds a role to this service</span> </button>
<select id="rolesSelect"></select>
<script type="text/javascript">
ExecuteOrDelayUntilScriptLoaded(retrieveCurrentListProperties, "SP.js");
function retrieveCurrentListProperties() { 

var clientContext = new SP.ClientContext("/sites/documentation");
var oList = clientContext.get_web().get_lists().getByTitle("Roles");
var camlQuery = new SP.CamlQuery();
camlQuery.set_viewXml('<View><Query></Query></View>');
this.collListItem = oList.getItems(camlQuery);
clientContext.load(collListItem);
clientContext.executeQueryAsync(onQuerySucceeded, onQueryFailed);
}
function onQuerySucceeded()
{
var listItemInfo = '';
var listItemEnumerator = collListItem.getEnumerator();
$("#rolesSelect").append('<option value=""></option>');    
while (listItemEnumerator.moveNext()) 
{
    var oListItem = listItemEnumerator.get_current();
    $("#rolesSelect").append('<option value="' + oListItem.get_item("Title") + '">'+ oListItem.get_item("Title") +' </option>'); 
}
}

function onQueryFailed(sender, args)
{
alert('Request failed. ' + args.get_message() + 
    '\n' + args.get_stackTrace());

}
</script>

What am I'm doing wrong??

Answer 1

You break everything with with this script-tag:

<script language="javascript" src="/_layouts/15/sp.js"></script>

Remove this one and your script should work just fine