nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

Can you use dojo on.once() with map::update-end event?

JerryGarcia

If so, can someone provide example code?

Thanks!

Finde mehr Beiträge mit dem Tag

Accepted answers

RobertScheitlin__GISP

Jerry,

I use dojo on.once quit often in code.

on<SPAN class="punctuation token">.</SPAN><SPAN class="token function">once</SPAN><SPAN class="punctuation token">(</SPAN>map<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"update-end"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="keyword token">function</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">{</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="comment token">// will only fire once...</SPAN>
<SPAN class="punctuation token">}</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">;</SPAN>‍‍‍<SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

All comments

thejuskambi

Hello Jerry,

I am not able to understand the objective of a example. on.once is a method in dojo, used to listen to an event only once. it would be similar to code below.

<SPAN class="keyword token">var</SPAN> handle <SPAN class="operator token">=</SPAN> <SPAN class="token function">on</SPAN><SPAN class="punctuation token">(</SPAN>map<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"click"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="keyword token">function</SPAN><SPAN class="punctuation token">(</SPAN>evt<SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">{</SPAN>
&nbsp;&nbsp; <SPAN class="punctuation token">.</SPAN><SPAN class="punctuation token">.</SPAN><SPAN class="punctuation token">.</SPAN>
&nbsp;&nbsp; handle<SPAN class="punctuation token">.</SPAN><SPAN class="token function">remove</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">;</SPAN>
<SPAN class="punctuation token">}</SPAN><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

It does not matter, which event. you can use on.once on any event, which you would like to listen just once.

JerryGarcia

Thanks. But, it is not always that simple... I want my code to fire only once. I have a couple callbacks when the event occurs. So... I need to wait until the callbacks are finished or, I was thinking, use the nifty on.once dojo functionality. I'm still not clear how to invoke it's magic.

None of the following works:

on.once(...);

on(...).once();

handle.once();

RobertScheitlin__GISP

Jerry,

I use dojo on.once quit often in code.

on<SPAN class="punctuation token">.</SPAN><SPAN class="token function">once</SPAN><SPAN class="punctuation token">(</SPAN>map<SPAN class="punctuation token">,</SPAN> <SPAN class="string token">"update-end"</SPAN><SPAN class="punctuation token">,</SPAN> <SPAN class="keyword token">function</SPAN><SPAN class="punctuation token">(</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">{</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="comment token">// will only fire once...</SPAN>
<SPAN class="punctuation token">}</SPAN><SPAN class="punctuation token">)</SPAN><SPAN class="punctuation token">;</SPAN>‍‍‍<SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN>

JerryGarcia

I see. Pretty simple. Thanks!

Anonymous User

This works as long as the dojo.on module is called first, like so:

on<SPAN class="" style="border: 0px; font-weight: inherit;">.</SPAN><SPAN class="" style="color: #d74444; border: 0px; font-weight: inherit;">once</SPAN><SPAN class="" style="border: 0px; font-weight: inherit;">(</SPAN>map<SPAN class="" style="border: 0px; font-weight: inherit;">,</SPAN> <SPAN class="" style="color: #669900; border: 0px; font-weight: inherit;">"update-end"</SPAN><SPAN class="" style="border: 0px; font-weight: inherit;">,</SPAN> <SPAN class="" style="color: #0077aa; border: 0px; font-weight: inherit;">function</SPAN><SPAN class="" style="border: 0px; font-weight: inherit;">(</SPAN><SPAN class="" style="border: 0px; font-weight: inherit;">)</SPAN><SPAN class="" style="border: 0px; font-weight: inherit;">{</SPAN>
&nbsp;&nbsp;&nbsp; <SPAN class="" style="color: slategray; border: 0px; font-weight: inherit;">// will only fire once...</SPAN>
<SPAN class="" style="border: 0px; font-weight: inherit;">}</SPAN><SPAN class="" style="border: 0px; font-weight: inherit;">)</SPAN><SPAN class="" style="border: 0px; font-weight: inherit;">;</SPAN><CODE><SPAN style="color: #3d3d3d;">require(["dojo/on"],
</SPAN>function(on) {

<SPAN class="" style="color: #999999; border: 0px; font-weight: inherit;">});</SPAN>

Thanks for this great tip!

Nimm an der Diskussion teil

Angemeldete Mitglieder können Beiträge verfassen, Updates folgen und mehr. Neu hier? Registriere ein kostenloses Konto.

Schnellzugriffe

Community Help
Find useful guides, FAQs, and documents to help you navigate and make the most of Esri Community.