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@spawnrider
Created August 8, 2019 13:50
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/*--- 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;
}
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