How to clear the contents of a glide list using a client script

[chadlockwood]

I have a checkbox and a list collector(glide_list) on a catalog item. if the checkbox is checked(true), the glide_list is visible(via UI policy). If the requestor adds items to the glide_list but then unchecks the checkbox, I want to clear the contents of the glide_list.

In the JavaScript Executor, I have run the following:

var a = g_form.getValue('IO:81332e394f2ae200b8ec7f75f110c77e');
alert(a);
var b = [];
g_form.setValue('IO:81332e394f2ae200b8ec7f75f110c77e', b);

Lines 1&2 successfully collect the contents of the glide_list and display them as a comma-separated list of sys_ids, as expected. Lines 3&4 appear to successfully set the value of the field to an empty string, however, the display values remain in the field. If I run lines 1&2 again, the alert appears to return nothing.

Additionally, I have an onSubmit client script that shows an error message if the checkbox is checked and the glide_list is empty. If I run the above code and click Submit, the error message appears, as if the glide_list is empty, even though the display values remain.

Is there another way to clear the contents of a glide_list using a client script? Or do I need to find some way to re-render the glide_list after I've cleared it out?

[chadlockwood]

Dave,

It is very likely that your solution would work, and I have seen that article in my search. However, my understanding is that the DOM manipulation will not work in Service Portal. Could you verify that for me?

[pbo]

Hi

I have the same requirement ie clearing a list_collector( glide_list) when a checkbox field is uncheck.

I tried to put code described in (https://community.servicenow.com/external-link.jspa?url=http%3A//fruitionpartners.eu/blog/2013/11/18... ) in catalog client script (onchange of checkbox field) but this doesn't work

When I uncheck the checkbox field, catalog script is called but doesn't clear the list collector

Any idea ?

[chadlockwood · Accepted solution]

Patrick,

Here is what I did:

First, open your catalog item, right-click the window portion that holds the items you select, then click Inspect.(assuming you are using Chrome)

Look for the "name" attribute, should look something like:

name="select_0IO:81332e394f2ae200b8ec7f75f110c77e"

Copy the value of the name attribute, including "select_".

Add this code to your script to clear the values:

g_form.clearValue('<variable_name>');
g_form.clearOptions('select_0IO:71332c394e2ae212b8ec6f65f110c66e');//replace with your "select_" value

I believe the system technically recognizes the glide_list as two separate fields which is why both lines are necessary.

Hope this helps.

[pbo]

Chad,

Thanks for your answer.

I found the 'name' attribute for this variable and added a g_form.clearOptions in my catalog client script.

But I found that when this field is unlock , selected values are still displayed (but not stored as variables in ritm which is good)

I tried to 'unlock' the glide_list variable before the clearOptions but didn't succeed

PS : I saw details in an old article Lock/Unlock glide_list and URL Fields With Client Scripts - ServiceNow Guru but was not able to do the same in catalog request variable set

[chadlockwood]

Patrick,

Here is the code we use to lock/unlock the glide_list:

function onChange(control, oldValue, newValue, isLoading) {
   if (isLoading || newValue == '') {
   return;
   }
   g_form.clearMessages();
   //Type appropriate comment here, and begin script below
   if(newValue == 'Car'){

   //get all elements that are of tag <button>
   var abuttons = document.getElementsByTagName("button");

   //loop through all of the button elements
   for (var ai = 0; ai < abuttons.length; ai++) {

   //get the button element by ID
   var ab = gel(abuttons[ai]);

   //if the button ID contains '_unlock' continue
   if(ab.id.indexOf('_lock') > -1){
   var alockBtn = gel(ab.id);
   var atmpID = ab.id.replace('_lock',"");

   //setup the unlock function
   lock(alockBtn, atmpID,atmpID + '_edit', atmpID + '_nonedit', 'select_0' + atmpID, atmpID + '_nonedit');
   }
   }
   }
   if(newValue == 'Boat'){
   //get all elements that are of tag <button>
   var sbuttons = document.getElementsByTagName("button");

   //loop through all of the button elements
   for (var si = 0; si < sbuttons.length; si++) {

   //get the button element by ID
   var sb = gel(sbuttons[si]);

   //if the button ID contains '_unlock' continue
   if(sb.id.indexOf('_unlock') > -1){
   var sunlockBtn = gel(sb.id);
   var stmpID = sb.id.replace('_unlock',"");

   //setup the unlock function
   unlock(sunlockBtn, stmpID,stmpID + '_edit', stmpID + '_nonedit', 'select_0' + stmpID, stmpID + '_nonedit');
   }
   }
   }
}

This applies to onChange of a dropdown with choices: Car and Boat

If Car is selected, we do not want to allow choices from the Boat glide_list so we lock it. The glide_list does not work the same way in Service Portal so this client script UI Type is Desktop.