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Using addEventListener on multiple elements, avoid TypeError when particular element not found

I'm using two simple addEventListener mouseenter and mouseleave functions respectively to play and stop animations (Bodymovin/SVG animations, though I suspect that fact is irrelevant).
So, the following works fine:
document.getElementById('animationDiv').addEventListener('mouseenter', function(){
animation.play();
})
(The HTML couldn't be simpler: The relevant part is just an empty div placeholder filled by script - i.e., <div id="animationDiv"></div>.
I can place that in the same file as the one that operationalizes the animation code, or I can place it in a separate "trigger" file, with both files (and other others necessary to processing) loaded in the site footer.
The problem arises when I need to be able to set triggers for any of multiple similar animations that may or may not appear on a given page.
If only one of two animatable elements are present on a page, then one of two sets of triggers will throw an error. If the first of two such triggers is not present, then the second one will not be processed, meaning that the animation will fail. Or at least that's what it looks like to me is happening.
So, just to be clear, if I add the following two triggers for the same page, and the first of the following two elements is present, then the animation will play on mouseenter. If only the second is present, its animation won't be triggered, apparently because of the error thrown on the first.
document.getElementById('firstAnimationDiv').addEventListener('mouseenter', function(){
firstAnimation.play();
})
document.getElementById('secondAnimationDiv').addEventListener('mouseenter', function(){
secondAnimation.play();
})
At present I can work around the problem by creating multiple trigger files, one for each animation, and setting them to load only when I know that the animatable element will be present, but this approach would get increasingly inefficient when I am using multiple animations per page, on pages whose content may be altered.
I've looked at try/catch approaches and also at event delegation approaches, but so far they seem a bit complicated for handling this simple problem, if appropriate at all.
Is there an efficient and flexible standard method for preventing or properly handling an error for an element not found, in such a way that subsequent functions can still be processed? Or am I missing something else or somehow misreading the error and the function failure I've been encountering?
WHY I PICKED THE ANSWER THAT I DID (PLUS WORKING CODE)
I was easily able to make the simple, directly responsive answer by Baoo work.
I was unable to make the answers below by Patrick Roberts and Crazy Train work, though no doubt my undeveloped js skills are entirely at fault. When I have the time, or when the issue next comes up for me in a more complex implementation (possibly soon!), I'll take another look at their solutions, and see if I can either make them work or if I can formulate a better question with fully fledged coding examples to be worked through.
Finally, just to make things clear for people who might be looking for an answer on Bodymovin animations, and whose js is even weaker than mine, the following is working code, all added to the same single file in which a larger set of Bodymovin animations are constructed, relieving me of any need to create separate trigger files, and preventing TypeErrors and impaired functionality.
//There are three "lets_talk" animations that can play - "home," "snug," and "fixed"
//and three types of buttons needing enter and leave play and stop triggers
let home = document.getElementById('myBtn_bm_home');
if (home) home.addEventListener('mouseenter', function() {
lets_talk_home.play();
});
if (home) home.addEventListener('mouseleave', function() {
lets_talk_home.stop();
});
let snug = document.getElementById('myBtn_bm_snug');
if (snug) snug.addEventListener('mouseenter', function() {
lets_talk_snug.play();
});
if (snug) snug.addEventListener('mouseleave', function() {
lets_talk_snug.stop();
});
let fixed = document.getElementById('myBtn_bm_fixed');
if (fixed) fixed.addEventListener('mouseenter', function() {
lets_talk_fixed.play();
});
if (fixed) fixed.addEventListener('mouseleave', function() {
lets_talk_fixed.stop();
});
At typical piece of underlying HTML (it's generated by a PHP function taking into account other conditions, so not identical for each button), looks like this at the moment - although I'll be paring away the data-attribute and class, since I'm not currently using either. I provide it on the off-chance that someone sees something significant or useful there.
<div id="letsTalk" class="lets-talk">
<a id="myBtn" href="#"><!-- a default-prevented link to a pop-up modal -->
<div class="bm-button" id="myBtn_bm_snug" data-animation="snug"></div><!-- "snug" (vs "fixed" or "home" is in both instances added by PHP -->
</a>
</div>
Obviously, a more parsimonious and flexible answer could be - and probably should be - written. On that note, correctly combining both the play and stop listeners within a single conditional would be an obvious first step, but I'm too much of a js plodder even to get that right on a first or second try. Maybe later/next time!
Thanks again to everyone who provided an answer. I won't ask you to try to squeeze the working solution into your suggested framework - but I won't ask you not to either...

Just write your code so that it won't throw an error if the element isn't present, by simply checking if the element exists.
let first = document.getElementById('firstAnimationDiv');
if (first) first.addEventListener('mouseenter', function() {firstAnimation.play();});

You could approach this slightly differently using delegated event handling. mouseover, unlike mouseenter, bubbles to its ancestor elements, so you could add a single event listener to an ancestor element where every #animationDiv is contained, and switch on event.target.id to call the correct play() method:
document.getElementById('animationDivContainer').addEventListener('mouseover', function (event) {
switch (event.target.id) {
case 'firstAnimationDiv':
return firstAnimation.play();
case 'secondAnimationDiv':
return secondAnimation.play();
// and so on
}
});
You could also avoid using id and use a more semantically correct attribute like data-animation as a compromise between this approach and #CrazyTrain's:
document.getElementById('animationDivContainer').addEventListener('mouseover', function (event) {
// assuming <div data-animation="...">
// instead of <div id="...">
switch (event.target.dataset.animation) {
case 'first':
return firstAnimation.play();
case 'second':
return secondAnimation.play();
// and so on
}
});

First, refactor your HTML to add a common class to all of the placeholder divs instead of using unique IDs. Also add a data-animation attribute to reference the desired animation.
<div class="animation" data-animation="first"></div>
<div class="animation" data-animation="second"></div>
The data- attribute should have a value that targets the appropriate animation.
(As #PatrickRobers noted, the DOM selection can be based on the data-animation attribute, so the class isn't really needed.)
Since your animations are held as global variables, you can use the value of data-animation to look up that variable. However, it would be better if they weren't global, but were rather in a common object.
const animations = {
first: null, // your first animation
second: null, // your second animation
};
Then select the placeholder elements by class, and use the data attribute to see if the animation exists, and if so, play it.
const divs = document.querySelectorAll("div.animation");
divs.forEach(div => {
const anim = animations[div.dataset.animation];
if (anim) {
anim.play(); // Found the animation for this div, so play it
}
});
This way you're guaranteed only to work with placeholder divs that exist and animations that exist.
(And as noted above, selection using the data attribute can be done const divs = document.querySelectorAll("div[data-animation]"); so the class becomes unnecessary.)

issues with Raphaël and removing objects within svg

if you open the code pen there is a fire button. it will launch a bunch of ellipses and then when it hits it will cause a burst. if you look the ellipses ,which there are two sets of, they are still there. I have tried using the below
d3.selectAll("ellipse").remove()
$("ellipse").remove()
$("ellipse").each(function(){this.remove()})
http://codepen.io/daniel667/pen/QwMWrm
the code pen above will help show what im talking about the second fire button to the far right is what ive been trying to use to kill the ellipses so I don't wait for the animation the functions at the very bottom.

I would create a Raphael set, or an array and store the elemets in that, so you can reference them later to remove. If they will be used repeatedly, it may be worth not removing them, but just hiding them rather than recreating each time.
var mySet;
...
mySet = paper.set();
mySet.push( circi );
....
function throwss() {
mySet.forEach( function( el ) { el.remove(); });
}
Example: codepen
For speed, you may also want to look into Velocity.js, also be aware for animation filters can be quite resource heavy.

Combine two line of codes in one function with JavaScript

I'm using Cycle slideshow and setTimeout() to give it seconds of delay
I want to to combine these two line of codes below to execute them simultaneously. But, I don't know how to accomplish this in JavaScript.
$('#slideshow').cycle('resume');
$('#slideshow').cycle({
sync: false,
speed: 300,
})
I want to put them in one line like this:
$('#slideshow').cycle(??????///here is your help////??????");
If I don't do this, the slide show, again, starts from the initial point and I don't want it.
How may I solve this?

Without looking in detail at the plugin's source code, I think from your description, that the plugin automatically starts from beginning whenever you set its options. That seems reasonable, as the plugin likely has to recalculate things from scratch whenever its options are changed.
Can you set the options once, e.g. during initialization, halting it then if necessary:
$('#slideshow').cycle({sync:false, speed:300}).cycle('pause');
Later, when you want to start the show, just resume it
$('#slideshow').cycle('resume');
Alternatively, you could look into setting the global options before initializing the slideshows.

try this:
$('#slideshow').cycle('resume').cycle({sync: false,speed:300,});

How to harness control of my JQuery coded sliding divs?

Essentially I have 4 divs that take turns sliding in and sliding out with delays and then it recalls the function. Like so:
$(document).ready (function bradslide(){
$("#slide1").delay('1000').slideDown('1000').delay('6000').slideUp('1000');
$("#slide2").delay('9000').slideDown('1000').delay('6000').slideUp('1000');
$("#slide3").delay('17000').slideDown('1000').delay('6000').slideUp('1000');
$("#slide4").delay('25000').slideDown('1000').delay('6000').slideUp('1000', 'swing', bradslide);
}
);
Let me say that this works fine, but that I am open to cleaning it up or making it easier or more up to standard if suggestions are made.
However my question is this: How can I arrange this so that the end user can manipulate the animation. This slides through the divs on its own, but ideally I would like to have a couple buttons to click to go backward or forwards (I think you get the idea).
Any suggestions of how or where to begin would be greatly appreciated. I imagine I might have to scrap this little piece of code as it stands. Thanks in advance guys.

Despite my own comment, I do have some general advice:
Look into using classes instead of IDs, and then use jQuery's DOM-traversal methods to identify what the next slider candidate is. Tracking the "currentSlide" and then targeting the "nextSlide" (identified with a .next() perhaps?) means that you can add any number of slider divs (with a class instead of ID, remember?) and still have it work.
The user controls (next, prev, or selecting a specific slide) simply interrupt the timer (probably a setTimeout instead of .delay()) and then invoke the exact same function that brings the next slide into place.
To make code more reusable and flexible, you should use some variables. For example, if your slide duration is going to be 1000, you would have var duration = 1000 scoped to an appropriate place (the document ready function is fine... or the sliding function) and then in your function call (whatever it ends up looking like), you would use .slideDown(duration). Then you can set that value to whatever you want and update it easily later.
Extending on the above, you could even build an API allowing you to pass values into your custom slider function:
var bradslide = function(container, delay, duration) {
// do stuff with a parent container, some delay value, and a duration value
};
bradslide('sliderParent', 6000, 1000);

What is the best way to implement multiway toggle using javascript/jQuery?

I have a div that can display 3 images (in the background) each indicating the 'state' of some variable: i.e., partial, full and none. For each of these states I have images: partial.gif, full.gif and none.gif (i.e., these are background images of that div)
Need: Circular queue like toggling effect for changing the images in this order partial -> full -> none -> partial
So if the current image is 'partial.gif' and the user clicks the div the background image changes to the next one in the sequence i.e., full.gif (and if it is currently full.gif it changes to none.gif and that to partial.gif and so on).
Naive solution: have a bunch of if/else's or switch-case and check the current one (image) and then decide based on array look up which is the next one. Is this the best way of doing it? Can I leverage jQuery's toggle function somehow?
(PS: It need not be restricted to images, but could also be for different background color sequences etc., I'd like to know what it is a good 'generic' way of doing it i.e., The example may be specific for background images but if I changed part of that code for background-color or font it should still work. I don't want it to be purely generic, but just enough so it is easy to modify for other attributes. If not, that's fine too. Just a thought :)

http://api.jquery.com/toggle-event/
To be precise http://api.jquery.com/toggle-event/#example-0
does exactly what you wanted...
$("#div1").toggle(
function() {
$(this).css("background-image","url(full.png)")
},
function() {
$(this).css("background-image","url()")
},
function() {
$(this).css("background-image","url(partial.png)")
}
});
UPDATE fn.toggle was removed from jQuery
Here are relevant posts
Where has fn.toggle( handler(eventObject), handler(eventObject)...) gone?
Toggle stopped working after jquery update

As long as it's a CSS-based solution (where you can just switch classes), you could do something like this (untested code):
$('#element').click(function() {
// get current css class value.
var class = $(this).attr('class');
// determine/increment number.
var nextNumber = parseInt(class.charAt(class.length - 1)) + 1;
// if too high, reset to first one.
if (nextNumber > 3) {
nextNumber = 1;
}
// remove old class and add new class.
$(this).removeClass(class).addClass('my_class' + nextNumber);
});
Assumption being made here that you only have one CSS class applied to the element at a time. But if that's not the case, I'm sure you can find a workaround/tweak for this.
And this is just generic enough where you can swap out your CSS class definitions without impacting the script functionality.