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; | |
} |
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