Count on Dropdown choices

[njguy]

is there an easy way to get the count on the number of choices available in a drop down list?

Thanks

Tom

[GGandhi]

Re: Count on Dropdown choices

if you are using in a dialog, add this to the onRenderComplete
assuming you have a control named food as dropdown and the option total is 4 then

var t1 = (document.getElementById('DLG1.V.R1.FOOD')).length-1;
alert(t1);

that should work, if you are using anywhere else then you should use the inspector to see the naming of the control and substitute accordingly.

[Davidk]

Re: Count on Dropdown choices

You can also do this... assuming you're using a Dropdown control... and not a Textbox configured as a Lookup/Edit-Combo

var dd = {dialog.Object}.getPointer('ddTest');
var ddCnt = dd.length;

If you're going to use Ghandi's code then you should probably make it a bit safer...

var t1 = (document.getElementById('{dialog.ComponentName}.V.R1.FOOD')).length-1;

or even a bit shorter...

var t1 = $('{dialog.ComponentName}.V.R1.FOOD').length-1;

Depending on the properties you set for the Dropdown control... you may, or may not, have to subtract from the count.
If you have Do Nothing set, and no pre or post choices then no subtraction is needed.
If you have Add to List set, then subtract 1. If you have pre or post choices set, you'd have to decide if you want to subtract those as well.

[njguy]

Re: Count on Dropdown choices

Thanks all...

[njguy]

Re: Count on Dropdown choices

David ....when I execute the code below to refresh the drop down I need to execute this twice to get the correct number of items....thoughts?

The first time this runs it gives me a value of 11 which is all the items even though it should be 2 because of the filter. If I run it again it will return a 2


function refreshWidthDropdown() {
var plantmach = {dialog.Object}.getValue('plant');
{dialog.Object}.refreshDropdownBoxChoices('machine_width','plantname="'+plantmach+'"');

var ddown = {dialog.Object}.getPointer('machine_width');
var ddownCnt = ddown.length;
alert(ddownCnt);

}

[Davidk]

Re: Count on Dropdown choices

Tom,

This is happening because Javascript is asynchronous. The method .refreshDropdownBoxChoices() is firing off an Ajax Callback. So... we're doing a round-trip to the server... but meanwhile... the Javascript to get a pointer and count is running. It's finished long before the server has returned anything.

You could put a setTimeout into your code and wait a bit. The only problem with that is that you never really know how long it's going to take. Try this and see how things are... here we're waiting half a second...

setTimeout(function(){
	var ddown = {dialog.Object}.getPointer('machine_width');
	var ddownCnt = ddown.length;
	alert(ddownCnt);
},500);

Another, safer way, is to use the Client-side event afterAjaxCallbackComplete. Using this you'd remove the .getPointer() etc. code from your Javascript function... and put it into the afterAjaxCallbackComplete event. This way... you're sure when the callback is done. Even then, you have to wait a bit for the control to get reset... but it's safer. Here's we're testing the function completing... and then grabbing the dropdown count. We still need to use a setTimeout, but now it's much less than half a second.

try {
	if(e.xbasicFunctionName == 'system:refreshDropddownBox'){
		setTimeout(function(){
			var ddown = {dialog.Object}.getPointer('machine_width');
			var ddownCnt = ddown.length;
			alert(ddownCnt);
		},100);
	}
}
catch(err) {}

[njguy]

Re: Count on Dropdown choices

Thanks David I will give it a try