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A utility function, for Greasemonkey scripts, that detects and handles AJAXed content.
/*--- waitForKeyElements(): A utility function, for Greasemonkey scripts,
that detects and handles AJAXed content.
Usage example:
waitForKeyElements (
"div.comments"
, commentCallbackFunction
);
//--- Page-specific function to do what we want when the node is found.
function commentCallbackFunction (jNode) {
jNode.text ("This comment changed by waitForKeyElements().");
}
IMPORTANT: This function requires your script to have loaded jQuery.
*/
function waitForKeyElements (
selectorTxt, /* Required: The jQuery selector string that
specifies the desired element(s).
*/
actionFunction, /* Required: The code to run when elements are
found. It is passed a jNode to the matched
element.
*/
bWaitOnce, /* Optional: If false, will continue to scan for
new elements even after the first match is
found.
*/
iframeSelector /* Optional: If set, identifies the iframe to
search.
*/
) {
var targetNodes, btargetsFound;
if (typeof iframeSelector == "undefined")
targetNodes = $(selectorTxt);
else
targetNodes = $(iframeSelector).contents ()
.find (selectorTxt);
if (targetNodes && targetNodes.length > 0) {
btargetsFound = true;
/*--- Found target node(s). Go through each and act if they
are new.
*/
targetNodes.each ( function () {
var jThis = $(this);
var alreadyFound = jThis.data ('alreadyFound') || false;
if (!alreadyFound) {
//--- Call the payload function.
var cancelFound = actionFunction (jThis);
if (cancelFound)
btargetsFound = false;
else
jThis.data ('alreadyFound', true);
}
} );
}
else {
btargetsFound = false;
}
//--- Get the timer-control variable for this selector.
var controlObj = waitForKeyElements.controlObj || {};
var controlKey = selectorTxt.replace (/[^\w]/g, "_");
var timeControl = controlObj [controlKey];
//--- Now set or clear the timer as appropriate.
if (btargetsFound && bWaitOnce && timeControl) {
//--- The only condition where we need to clear the timer.
clearInterval (timeControl);
delete controlObj [controlKey]
}
else {
//--- Set a timer, if needed.
if ( ! timeControl) {
timeControl = setInterval ( function () {
waitForKeyElements ( selectorTxt,
actionFunction,
bWaitOnce,
iframeSelector
);
},
300
);
controlObj [controlKey] = timeControl;
}
}
waitForKeyElements.controlObj = controlObj;
}
@terabyte

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commented Dec 2, 2014

@BrockA : could we please get this under a BSD or Apache 2.0, or some other compatible license? We'd like to include it in https://github.com/palantir/stash-disapproval-plugin which is apache 2.0.

@terabyte

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commented Dec 2, 2014

(also, either way, deep gratitude for writing it!)

@Lamieur

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commented Dec 22, 2014

Something's wrong with current Firefox, the script just stops on targetNodes.each(). Still works on SeaMonkey or older Firefox, so it's not just me or the page I'm working with, or is it?

What I did was:

-        targetNodes.each ( function () {
-            var jThis        = $(this);
+        for (var i = 0; i < targetNodes.length; i++) {
+            var jThis        = $(targetNodes[i]);

And looks like it works, but I'm not sure if I'm not making some type-casting crime or whatever ;)

@kepkin

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commented Jan 29, 2015

It fails to work when other javascript framework use $() as alias. So it's better to use jQuery() explicitly.
You can get update from my fork
https://gist.github.com/kepkin/ff99090c410ab1b5c8fa

@BrockA

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commented Nov 10, 2015

Huh, I've not been getting email alerts for this? But GitHub seems to email just fine.

@BrockA

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commented Nov 10, 2015

@terabyte,
I don't know if you still want/need this, but I consider it:

Creative Commons, Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)

I'm not going to lawyer-up in any case.

@GollyJer

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commented Nov 17, 2015

Hey Brock. Thanks for your help over on StackOverflow!
I'm looking to post my greasemonkey script on GreasyFork and it @includes waitForKeyElements. However, GreasyFork doesn't allow includes of GitHub scripts by default and someone else is hosting a version of your script on GreasyFork.

GreasyFork has Github sync functionality.

A GitHub webhook connected with Greasy Fork makes it so any push to your GitHub repository automatically updates your scripts on Greasy Fork in a matter of minutes.

I'd love to @include your script instead of a copy. If you aren't interested in creating a GreasyFork account let me know and I'll use the already posted script. Otherwise, point me to the GreasyFork version.

Best!
Jeremy

@BrockA

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commented Nov 17, 2015

@GollyJer, Interesting, there appear to be at least 4 copies of waitForKeyElements on Greasy Fork:

3 out of 4 of them even credit me; I can die in peace! :D

Anywho, I've no interest in creating a Greasy Fork account at this time. Use whichever version/method that works best for you.

@panayot-zhi

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commented Mar 23, 2016

Seems the unacredited version is mine, fixed now, Cheers :)

@GollyJer You could also import this script as a resource, like this :
// @resource waitForKeyElements https://gist.githubusercontent.com/BrockA/2625891/raw/9c97aa67ff9c5d56be34a55ad6c18a314e5eb548/waitForKeyElements.js

then read it with GM_getResourceText("waitForKeyElements ") and inject it on page or eval it in script.

@terabyte

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commented Oct 4, 2016

@BrockA - Apparently github is delivering notifications 11 months delayed? wtf... Anyways, many thanks for chiming in! I might still like to use it but I don't maintain disapproval plugin much these days, so not sure if I will ever get to it. Thanks for contributing to the hive mind just the same! =D

@GollyJer

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commented Nov 14, 2016

Thanks for that @panayot-zhi Updated my script to point directly at the gist.
https://greasyfork.org/en/scripts/13968-gollyjer-s-auto-expand-google-search-tools

@doyousketch2

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commented Jan 2, 2017

@panayot-zhi - Even better yet, run the address through Git.io to get a shortened URL.
// @require https://git.io/vMmuf
Then use function normally.

@hellonearthis

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commented Jan 9, 2017

@john-cj

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@mjblay

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commented Mar 12, 2018

Not sure if this has already been accomplished, but I couldn't find an example of this without the need for JQuery. I forked this and removed reliance on JQuery, though I had to hobble it by disabling the iframe search. Might help some though, and it works for my project. Thanks for your work @BrockA

@insanid

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commented Mar 13, 2018

@mjblay What a crazy coincidence. I have been re-writing it as well within this past week to no longer rely on jQuery, and I also ended up removing the iframe feature until I had more time to re-write that part in vanillajs. I had published a gist a couple of days ago, but I removed it after encountering a few bugs. I checked out your Gist/Github account and couldn't find the fork. Are you planning on publishing it on Github?

@BrockA

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commented Mar 13, 2018

@mjblay, you're welcome.

@mjblay

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commented Mar 13, 2018

@insanid I inadvertently deleted it. I re-added the fork here: https://gist.github.com/mjblay/18d34d861e981b7785e407c3b443b99b. I haven't tested it thoroughly, but it seems to be working on a private site I maintain and use daily.

@Gallion

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commented Sep 17, 2018

Can this act within an iframe that is itself within an iframe?

@BrockA

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commented Sep 17, 2018

@Gallion, not directly but it can help. If you need to, open a question about that on some place like Stack Overflow and give details and a working test case or link to the target page.

@EliezerWu

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commented Dec 12, 2018

It's a very useful script but recently I met an issue. If waitForKeyElements already finds the element at the first run and the element disappears. The timer cannot be cleared since the element is not found anymore.

@BrockA

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commented Dec 12, 2018

@EliezerWu, Even when you set bWaitOnce to true?
Also, letting the timer keep running is not normally a problem.

Anyway, post a "Minimal, Complete, and Verifiable example" if you want me to investigate this further.

@josepelupi

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commented Aug 12, 2019

@BrockA,

I don't know if you still want/need this, but I consider it:

Creative Commons, Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)

I'm not going to lawyer-up in any case.

Hi =)
How can i do for commercial use?
It would be used to dynamically generate buttons with javascript codes to automate tasks in my work =)

thanks.

@BrockA

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commented Aug 12, 2019

@josepelupi, And anyone else who wants to use this commercially...

Consider this free to use commercially until your install base exceeds twenty-thousand users. At which point, any fee would probably consist of a modest (3 digits or less) donation to EFF or similar.

You could add a comment to your code: "Used by permission of github.com/BrockA until install base exceeds twenty-thousand users."

How can i do for commercial use?
It would be used to dynamically generate buttons with javascript codes to automate tasks in my work =)

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