How to review jQuery function execution related to specific events using Firebug? - javascript

I cannot for the life of me, after reading all of the documentation and probably twenty different Stack posts on the topic, figure out how to very simply view a log of JavaScript/jQuery function execution on a particular page using Firebug.
For example, I am attempting to determine which events are tied to a particular event (link being clicked, resulting in odd/unexpected behavior). I've heard over and over again that Firebug is the tool to use for this, but after ripping out the last few hairs remaining on my head over the last several hours, I can't figure it out.
Can someone please dummy-proof this for me? I'm not profiling. I'm not trying to look at the resources. I just want to see what JavaScript or jQuery code is executed as it relates to a specific user event (in this case, any link being clicked).

Related

Continuing a javascript after using .click() on a button which adds new DOM elements

I am a lowly operations employee without authorization to change the programs and permissions on my machine, and I would like to automate some highly repetitive data entry. I know there are a lot of programs that can do that, however, for the sake of this discussion we'll assume that I'm not allowed to have any of them and I can only script through the debug F12 menu in Chrome. I also probably don't understand half of these words as well as I should.
I have to run test cases on a third-party vendor's highly dynamic website, and I've already successfully written javascript which adds texts to elements in the DOM and presses the "next" button.
The problem is, upon .click()ing the "next" button, it takes time for the page to update, and the update creates new elements which weren't in the DOM when the script was initialized. I need to find a way to delay the execution of the script until the DOM contains all the elements I need to update.
As a really, really crude proof of concept I wrote the pre-filler for each page as a function, and I serially called each function at the end of the previous function, using setTimeout(nextfunct, 10000) to let the page update before executing the next line. (I was going to refine that by trying to create some kind of object listener instead of an arbitrary 10 second delay, but I wasn't even able to get that far.) This approach creates two errors.
1) The script seems to be checking whether the elements are on the DOM before the end of the setTimeout(), so it still gives me an error. If nextfunct is defined as
document.getElementById("doesntexistyet").value = "Fill Me";
console.log("nextfunct ran");
I will get the error message stating there is no element with the id "doesntexistyet" immediately, not after a delay of 10 seconds. The element on the next page will not update.
2) The DOM updating interrupts my script. In the above code, the console output will not ever appear in my console. If I comment out the missing element, so the function only prints a comment, it will still not appear in my console. However, if I comment out the code and I switch the setTimeout to 1ms, "nextfunct ran" will appear in my console, until the page updates, at which time the console will be deleted.
Are there ways around this which I can implement using only vanilla JS and a browser? I'm sure there's a keyword I can search for where someone has discussed this before, but it seems like the vast majority of JS autofilling discussions are oriented towards people designing code to be integrated into a website,
Thanks

How to check if JavaScript file is yet to loaded or loading

I am doing GUI automation of my website via Selenium (RobotFramework). The problem I am facing is:
When my automation script clicks on some element (button,link etc) which is supposed to perform some action, it dose nothing. This happening randomly. When we test is manually, it works all the time. One observation is, with slower machine/environment, this tends to happen more.
I suspect this is happening either due to some corresponding JS is not loaded yet or if there is any such thing called "action binding" with each elemetnt, has not happened.
Some question
- Is there a way to find out if all the JS calls are over?
- In case action binding happens, has it already bound or not.
Please share if you have any other solution.
do you know what is last to load on the page? This should be very easy to find out via Developer Tools in your browser of choice.
You can then easily use a Wait Until Keyword (there are many variations) to wait until that last item appears as you expect, then continue with your test. Setting the timeout length and interval will help control the overhead of time/performance.
Wait Until Element Is Visible id=finalElement 10 finalElement did not appear on the screen before timeout period
http://robotframework.org/Selenium2Library/Selenium2Library.html - please see the documentation for further examples and options in terms of keywords

How do I debug jQuery events using Firefox debugger?

I've been wracking my brain over this and cannot figure it out for the life of me.
Here's a test page I built for the sake of this discussion:
http://jsbin.com/garokalocu
Let's assume this page is very complex and I didn't build it, and I'm trying to see the code that runs when the user clicks "Do It." So I open the debugger, open the side pane and click "Events." I checkmark the click event for #execute which is the button.
Now I click the button, and the code hits the breakpoint. But strangely, the name "Bob" has already been filled in, so clearly it flew right past the actual code, and lands me here:
I don't understand what's going on here. So I tried something else, a new feature in Firefox that I thought might be handy. If I inspect the code, there are little "ev" tags on certain DOM elements. Supposedly you can click those and see the code.
Well, that was fruitless. I'd be forever grateful if someone could please tell me how on earth to debug jQuery events, and see the actual code that gets executed. Thanks!
You see jQuery as the handler because you used jQuery to make those listeners. jQuery code is called when event is triggered. If you used normal JS addEventListener, they will show up in the event without having to step through.
According to the article here the feature is coming in Firefox 34, so if you use Firefox beta it should have the behavior you want.

How to generally find out what javascript controls the behavior of a general element on a webpage?

Look at this fiddle http://jsfiddle.net/52VtD/2635/
Inside it you can see one tooltip working.
Suppose we weren't looking at a fiddle though, and couldn't see the javascript source, but we wanted to know what was controlling this tooltip behavior?
The answer is
$("#tooltip1").tooltip();
So how do we find that answer using chrome or firefox inspector, or some other debug/browser inspector stuff? Preferably it would be quick, as opposed to downloading all .js files and prettifying them in an IDE and then manually searching.
There is no quick answer to this. You pretty much have to analyze a specific situation and see what clues you can then go look for.
In this particular case, you're going to suspect that there's an event listener attached to the #tooltip object. You can first look in the Chrome debugger for event listeners. Right click on the button, select Inspect Element, click on the Event Listeners tab and then look at the event listeners. In this particular case, you will see a bunch of them for that object. What you want is mouseout and mouseover. But, when you see where the event listeners are attached, it just take you to the internals of jQuery. This is a challenge with a library because it's the library that actually attached the event as part of some higher level API that the developer used.
So, now you know that jQuery was used to attach these events. You need to figure out where in the code these events where attached. To do this, you need to develop a theory about how the developer identified this particular object in jQuery. Since there is no particular structure to this simple document, the likely way that the developer found this particular object is with a "#tooltip" selector passed to some jQuery function. So, at this point, I would search all the JS in the page for "#tooltip" and see what you find.
While still in the Chrome debugger, you can hit Ctrl+F and enter #tooltip. Then, hit enter several times as it takes you to different uses of that and the third time, it will take you to:
$("#tooltip1").tooltip();
And, you will have your answer. Obviously, every problem like this is a bit different and it takes some detective work and searching to figure out what clues to search for in the Javascript. Some cases are much harder than others.
In *Chrome** you can bring up the developer tools buy clicking f12 and on the right you should see a tab titled "Event Listeners". Here you should see the event listeners for the page your are on.
This should have all the Event Listener info you could ever want :)

Facebook JS (FBJS) event listener

So I have looked through most of the facebook questions here and it has absolutely confirmed my thoughts. Facebook development may be among some of the worst I've ever used. I'll avoid my rant for now, but as a note to where I'm coming from: tried php sdk, worked decently out of the box, found out I need to put the functionality on a pages tab, can't iframe on pages tab, have to use FBML (which they are retiring in two months, yet I can't start testing the iframe approach yet)
Anyway, I run into FBJS at this point. It works "good enough" for most things, but for some reason I can't get an event registered to an object (a select box in particular interest) by adding a listener (as per FBJS documentation). I am able to add it directly to the html object and have it work, but this is not desirable and I would really like to know what I consider the proper way to do it, which involves seperation of logic and display.
What I want to happen: click on the select box, make a selection, display the text of the selection in an empty div (later on adding Ajax but one step at a time here)
Code:
<script>
var obj = document.getElementById('select-id');
obj.addEventListener('onchange',my_func);
function my_func(evt){
var inner = document.getElementById('div-id');
inner.setTextValue('hey'); // for testing purposes
}
</script>
The above code doesn't do anything when I make a change to the select box. However, this behaves as planned:
<select name="find_state" id="find_state" onchange="my_func();">
I will be grudgingly using this method as I develop, but would really love to know what I might be doing wrong or if anyone else has this issue? And if anyone has any opinions on the matter I would love to know of some form of facebook development recommendations as applications, pages, and tabs all appear to behave totally different from eachother, yet it seems that they all should be doing the same thing to me? Is there any unified way to develop across all three of these things, or am I missing something?
Thanks in advance, as well as for the past help!
I think it should be:
obj.addEventListener('change',my_func);
(instead of onchange)
Straight from Facebook documentation:
The third parameter [to addEventListener], boolean useCapture is required (it does not have a default value)
That means that you should have:
obj.addEventListener('change', my_func, false);
Use the following html and your events attached with .addEventListener() start to work. This seems to be undocumented "feature".
<select name="find_state" id="find_state" onmousedown="return true;">
This also enables the event to fire first time the user changes the value of select. Otherwise it would fire only on second onchange event.

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