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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. Forked for use without JQuery.
Usage example:
waitForKeyElements (
"div.comments"
, commentCallbackFunction
);
//--- Page-specific function to do what we want when the node is found.
function commentCallbackFunction (element) {
element.text ("This comment changed by waitForKeyElements().");
}
IMPORTANT: Without JQuery, this fork does not look into the content of
iframes.
*/
function waitForKeyElements (
selectorTxt, /* Required: The 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.
*/
) {
var targetNodes, btargetsFound;
targetNodes = document.querySelectorAll(selectorTxt);
if (targetNodes && targetNodes.length > 0) {
btargetsFound = true;
/*--- Found target node(s). Go through each and act if they
are new.
*/
targetNodes.forEach(function(element) {
var alreadyFound = element.dataset.found == 'alreadyFound' ? 'alreadyFound' : false;
if (!alreadyFound) {
//--- Call the payload function.
var cancelFound = actionFunction (element);
if (cancelFound)
btargetsFound = false;
else
element.dataset.found = 'alreadyFound';
}
} );
}
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
);
},
300
);
controlObj [controlKey] = timeControl;
}
}
waitForKeyElements.controlObj = controlObj;
}
@DinoChiesa

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@DinoChiesa DinoChiesa commented Jul 26, 2019

Thank you! Helpful.

@Luckz

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@Luckz Luckz commented Jul 28, 2020

This one's better for me than some competitors I tried. :3

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