Related
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.)
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,});
Initially I asked this Question and written my own plugin to achieve the same,But i am facing very strange issue regarding to css of table.
After applying the plugin table cells borders are getting dis-sorted.
jsFiddle of the problem: Problem demo
In fiddle you can see that after first cell of the first tr, the header border line and table border line don't line up. I want the border line of thead cells and td cells to line up.
Can anyone tell me how to achieve that?
Lets start by doing a bit of a clean up of the code you posted so I can actually read your code and maintain a firm grasp on reality while we go down this rabbit hole.
If you write clean code, your problems will be exceptionally easier to see.
So lets clean it up and watch as all the problems here reveal themselves.
Step one: Your jsFiddle sets it to run "onDomReady," which basically means you've got $(document).ready(...) calling all the code in the box, which is fine, except you're got another got $(document).ready(...) inside there. Lets change that.
Step two: Lets add some white space and proper indentation in there, and stop using these one letter variable names.
{} are scope brackets, they should indent, not cover everything, they let us know what part of scope something is in.
Don't write .each() loops on one line, this adds no value and makes your code confusing to read.
$t should be called something meaningful, lets try element, because it holds the $(this) element, which is the active element you're working with.
w should be called something meaningful, but since you only use it twice I'm just going with element.width().
o needs to be less ambiguious, lets go with obj.
Step three: Selection structures
if(typeof(i)=='number')o.height=i;
else if(typeof(i)=='object')o=i;
else if(typeof(i)=='undefined')o={height:300}
Break that up, make it readable. Saving lines doesn't make you a better program, writing clean and easily understandable code will.
Why not use the switch-case statement?
switch (typeof(i)){
case "number":
o.height=i;
break;
case "object":
o=i;
break;
case "undefined":
o={height:300};
break;
}
Step four: Don't in-line styles. Just don't. There's no reason to do it, and it makes everyone's life harder.
Instead, lets just place the styles gently into the style sheet where it belongs, and make the parent=$('...') line look like parent=$('<div><div></div></div>').appendTo('body');.
Step five: Closure doesn't pass any value to arguments
After a bit of clean up, we see this block of code:
self.width(self.width() -
function(width){
var parent,child;
if(width===undefined){
parent=$('<div><div></div></div>').appendTo('body');
child=parent.children();
width= (child.innerWidth()) - (child.height(99).innerWidth());
parent.remove();
}
return width;
}()
);
Okay, that's a problem. Lets cut out a few lines to point out the problem here:
self.width(
self.width() -
function(width){
/*...*/
if(width===undefined){
/*...*/
}
return width;
}()
);
So, a quick refresher on this pattern you have here:
(function(arg1){
/*code*/
})(data);
Data gets passed to arg1. Arg1 declaires a variable in the scope local to that function, it doesn't get anything from outside. Outside data is passed in through the set of () that call the function, which your code had left abandoned. Think of it this way:
var msg = function(text) {
alert(text);
};
Then you call it as...
msg("hello world");
What your closure is doing is almost the same thing, except where you define your function, you also call it. Thus...
(function(text) {
alert(text);
})("hello world");
So, you need to pass a value of some sort into there, other wise this whole thing is always undefined. Lets do that. What are we passing? I have no way to be sure. This is why programmers need to add comments to their code.
Step six: Comment your code so people other than yourself will look at this code and have not a damn clue what you truthfuly wanted to do, and can only guess. It's like you posted a 200 point bounty and didn't bother helping people who want to help you. Why are you doing this to yourself, dude? Why couldn't you just go //This is what this does to give me a hint? What did I ever do to you?
Step Seven: Lets see if we can make the JS changes work with the JS Fiddle
Great odin... that HTML's 2000 lines long?
Okay, I'm working with pastebin here for the sake of saving space in the post here.
Alright, you started off with this: http://pastebin.com/xjmm4cev
You're using a lot of no-wrap, and putting classes onto individual elements. You shouldn't have to do this on each HTML element, CSS takes care of that very effectively, so lets go ahead and just rip out all the nowrap=nowrap and class="header" stuff (we'll put it back in a moment, but only ONE per group, not each element).
Then lets get rid of the useless blank lines.
Lets run this through HTML tidy and get it nice and indented correctly.
http://pastebin.com/uHtSZ4h5
Much easier to read over. Okay, so what do we see here? Well, it looks like you keep going in circles, cutting and pasting the same thing again and again. You also in-line javascript such as using onchange and onclick attributes. This is generally an awful thing to do to your code, and makes it hard to maintain (as I'm sure you've seen with this 2000+ line beast of cut+paste 27 times in a row).
So, lets take a look here:
elements, not inside a form
Elements in a table that are outside of rows, but not head/body/footer sections of a table
Code that's a huge pain to maintain because it keep going in circles, if you need to change this, you're basically screwed.
Lets fix all that.
We're going to use events in the tags, rather than in-line things. So, all of those in-line onchange and click attributes get the boot.
All of these inputs that are just floating around need to get put into a form, and taken out of this place in tables that only rows or table sections belong in.
Figure out how we can not have excessive input elements, if we can help it.
What the heck is the )="" that you have on every input button? Deleted.
So, here's all of your hidden boxes: http://pastebin.com/LXZSkvyf which I've removed, because we don't have a anywhere.
And here's what the code looks like without all of these weird things in it: http://pastebin.com/MiaJTGpb
Much more readable, but still not quite there.
Step 8: What can you do to make the HTML of the table work better?
You're using Thead and Tbody, and that's good.
You're using attributes for things like cellpadding, that's bad.
You've given each body row an ID. I don't feel you needed to do this, but it's not always bad. However, I'll show you how you could work without it.
You give some selects a select-box class, but it's nowhere in the css. I've removed it.
You give a title attribute to the selects that says "option_value". The title attribute is generally used to make a tool-tip popup when you leave the mouse over something. I'm not sure what you're going to do here, but that's bound to confuse your user. I'd highly suggest giving something better than option_value in that place.
You keep using the ID Submit_FMS_AddDelivery. HTML ID tags are meant to be unique, and used only once on one element. You've got it 27 times, that's bad. I don't think you need an ID on it, so I've removed it.
You've also got input-btn going on, I'm removing it, because you haven't shown it's used anywhere.
You probably don't need any of these ID tags on select and TR to be honest, so I'm pulling them.
What's that look like? Basically, you've got what's almost just the data, in it's nice pure form. That's good. http://pastebin.com/UNS6CAtb
Step 9: What were you trying to do?
Lets step back and take a look here.
All you really wanted to do was keep a fixed header, but you've ended up doing a lot of JavaScript hacks and manipulating the DOM in a lot of places. We need to stop doing this. Is there a simpler way to do what you want?
I'll have to expand on how to make this function with the rest of your stuff, but I get up for work in a few hours. I'll update again with more... But we'll get there.
Right now, because I haven't fixed what I took out, it doesn't look right. But I'm tired.
So, here's where we are so far: http://jsfiddle.net/5C6z7/
Plus those inputs we took out (and will be going back in later, in a different way)
Looks like all you have to do is to take the padding into account: each cell has 3 px padding both left and righ so you have to add 6 px to the width:
$t.find('tr:first th').each(function(){cols.push($(this).width()+6);});
Otherwise the cells with only one word inside will "push" the actual width a bit wider so that the word will fit and other cells with space to move will compensate by becoming a bit narrower. The header and the body both do this independently with different contents which creates the difference in actual cell widths.
EDIT: For Firefox you also need to widen the table so that the cells fit. After calculating the column widths add
var actualWidth = $t.width()+cols.length*6;
$t.width( actualWidth );
And later change the wrapper to:
$wrap.css({width:actualWidth,height:o.height,overflow:'auto'});
EDIT 2: To have both the header and the body scroll simultaneously you need to wrap them both to an outer div that handles the scrolling.
var $outerWrap = $( '<div>' ).css( {width:"300px", overflow:'auto' } );
var $wrap=$('<div>').css(
{ width:actualWidth,height:o.height,"overflow-y":'auto', "overflow-x":'hidden' }
);
$firstRow.wrap( $outerWrap );
$firstRow.after( $wrap );
$wrap.append( $t );
Demo: http://jsfiddle.net/YcRTz/2/
What about replacing '<th>' tags with '<td>' tags?
No extra js code required.
http://jsfiddle.net/spQAh/7/
Okay so instead of troubleshooting or using anything complex, I came up with simple CSS + JS solution to your problem. Take a look at http://jsfiddle.net/TdLQT/
Obviously, the process of making header static, can be made dynamic, meaning trigger it after user scrolls a bit or have it there by default or count other object's position from top window and trigger static behavior when it reaches or exceeds certain pixels. I can provide that if you give me details on exact design of your HTML page.
Anyways, I as you can see, have used fixed pixel heights which you can choose not to or make them elastic or dynamic. What is important to know is that, though solution relies on JS a bit, output position is purely from CSS. I am using classes to manipulate the position.
the simple solution is that when you calculate the width of the column you do not include padding. So you need to change the line
$t.find('tr:first th').each( function() {
cols.push($(this).width());
});
to
$t.find('tr:first th').each( function() {
cols.push($(this).outerWidth());
});
if your cells have margins use .outerWidth(true)
This works in quirks mode with IE7&8 and Chrome IE8 has a problem in strict mode. However I believe that that problem is caused by the added scrollbar. If you want to use IE8 in strict mode you have to allow for the width of the vertical scrollbar..
i am using prettify, i am wondering if i can make it work with any code block, not requiring the prettyprint class.
else, how can i attach the class prettyprint dynamically, maybe using jquery. what i want to acheive is similar to stack overflow where code typed in the editor will be "pretty printed" in the preview and output.
i tried
$("#main").delegate("code", "ready", function() {
// this does not seem to run at all?
// intending to add the prettyprint class here
});
$(document).ready(function(){ $('code').addClass('prettyprint'); });
$(document).ready(<func>) runs <func> when the DOM is ready.
$('code') selects all code tags.
.addClass() adds the specified class to any elements it is passed (in this case, all of the code tags).
I don't think delegate() is necessary here. You just need to execute prettyPrint() every now and then to evaluate your preview. One solution might be to use setInterval to apply Prettify after every x seconds. Here's a quick example:
$('textarea').bind('keyup', function(e) {
val = this.value.replace(/<code>/gi, '<code class="prettyprint">');
$('#preview').html(val);
});
setInterval(function(){ prettyPrint(); }, 10000);
This would execute prettyPrint() every 10 seconds. It's not what I'd call perfect, but I think it does what you want. You'd probably also want to clear the interval if the user hasn't typed anything for a certain amount of time, but I hope this is enough to get you moving in the right direction.
I'm modifying some code from a question asked a few months ago, and I keep getting stymied. The bottom line is, I hover over Anchors, which is meant to fade in corresponding divs and also apply a "highlight" class to the Anchor. I can use base JQuery and get "OK" results, but mouse events are making the user experience less than smooth.
I load JQuery 1.3 via Google APIs.
And it seems to work. I can use the built in hover() or mouseover(), and fadeIn() is intact... no JavaScript errors, etc. So, JQuery itself is clearly "loaded". But I was facing a problem that it seemed everyone was recommending hoverIntent to solve.
After loading JQuery, I load the hoverIntent JavaScript. I've triple-checked the path, and even dummy-proofed the path. I just don't see any reasonable way it can be a question of path.
Once the external javascripts are (allegedly) loaded in, I continue with my page's script:
var $old=null;
$(function () {
$("#rollover a").hoverIntent(doSwitch,doNothing)
});
function doNothing() {};
function doSwitch() {
var $this = $(this);
var $index = $this.attr("id").replace(/switch/, ""); //extract the index number of the ID by subtracting the text "switch" from its name
if($old!=null) $old.removeClass("highlight"); //remove the highlight class from the old (previous) switch before adding that class to the next
$this.addClass("highlight"); //adds the class "highlight" to the current switch div
$("#panels div").hide(); //hide the divs inside panels
$("#panel" + $index).fadeIn(300); //show the panel div "panel + number" -- so if switch2 is used, panel2 will be shown
$old = $this; //declare that the current switch div is now "old". When the function is called again, the old highlight can be removed.
};
I get the error:
Error: $("#rollover a").hoverIntent is not a function
If I change to a known-working function like hover (just change ".hoverIntent" to ".hover") it "works" again. I'm sure this is a basic question but I'm a total hack when it comes to this (as you can see by my code).
Now, for all appearances, it SEEMS like either the path is wrong (I've zillion-checked and even put it on an external site with an HTTP link that I double-checked; it's not wrong), or the .js doesn't declare the function. If it's the latter, I must be missing a few lines of code to make the function available, but I couldn't find anything on the author's site. In his source code he uses a $(document).ready, which I also tried to emulate, but maybe I did that wrong, too.
Again, the weird bit is that .hover works fine, .hoverIntent doesn't. I can't figure out why it's not considered a function.
Trying to avoid missing anything... let's see... there are no other JavaScripts being called. This post contains all the Javascript the page uses... I tried doing it as per the author's var config example (hoverIntent is still not a function).
I get the itching feeling I'm just missing one line to declare the function, but I can't for the life of me figure out what it is, or why it's not already declared in the external .js file. Thanks for any insight!
Greg
Update:
The weirdest thing, since I'm on it... and actually, if this gets solved, I might not need hoverIntent solved:
I add an alert to the "doNothing" function and revert back to plain old .hover, just to see what's going on. For 2 of my 5 Anchors, as soon as I hover, doNothing() gets called and I see the alert. For the other 3, doNothing() correctly does NOT get called until mouseout. As you can see, the same function should apply for any Anchor inside of "rollover" div. I don't know why it's being particular.
But:
If I change fadeIn to another effect like slideDown, doNothing() correctly does NOT get called until mouseout.
when using fadeIn, doNothing() doesn't get called in Opera, but seems to get called in pretty much all other browsers.
Is it possible that fadeIn itself is buggy, or is it just that I need to pass it an appropriate callback? I don't know what that callback would be, if so.
Cheers for your long attention spans...
Greg
Hope I didn't waste too many people's time...
As it turns out, the second problem was 2 feet from the screen, too. I suspected it would have to do with the HTML/CSS because it was odd that only 2 out of 5 elements exhibited strange behaviour.
So, checked my code, dug out our friend FireBug, and discovered that I was hovering over another div that overlapped my rollover div. Reason being? In the CSS I had called it .panels instead of .panel, and the classname is .panel. So, it used defaults for the div... ie. 100% width...
Question is answered... "Be more careful"
Matt and Mak forced me to umpteen-check my code and sure enough I reloaded JQuery after loading another plugin and inserting my own code. Since hoverIntent modifies JQuery's hover() in order to work, re-loading JQuery mucked it up.
That solved, logic dictated I re-examine my HTML/CSS in order to investigate my fadeIn() weirdness... and sure enough, I had a typo in a class which caused some havoc.
Dumb dumb dumb... But now I can sleep.