Can't see problem in JS - javascript

I want that when mouse is over an image, an event should be triggered ONCE, and it should be triggered again only after mouse is out of that image and back again, and also at least 2 seconds passed.
If I leave my mouse over the image,it gets called like every milisecond,and by the logic of my function once you hover on the variable 'canhover' becomes 0 until you move mouse out
This code seems to have a bug and I cant see it. I need a new pair of eyes, but the algorithm is kinda logical
Working code :
<script type="text/javascript">
var timeok = 1;
function redotimeok() {
timeok = 1;
}
//
function onmenter()
{
if (timeok == 1)
{
enter();
timeok = 0;
}
}
//
function onmleave()
{
setTimeout(redotimeok, 2000);
leave();
}
//
$('#cashrefresh').hover(onmenter,onmleave);
function enter(){
$("#showname").load('./includes/do_name.inc.php');
$("#cashrefresh").attr("src","images/reficonani.gif");
}
function leave(){
$("#cashrefresh").attr("src","images/reficon.png");
}
</script>

I don't know if this will solve your entire problem (since we don't have a detailed description of what it is), but instead of:
$('#cashrefresh').hover(onmenter(),onmleave());
try:
$('#cashrefresh').hover(onmenter,onmleave);
And the same thing here:
setTimeout(redotimeok, 2000); // just the function name
Also, I don't see where you ever set timeok to zero. Do you mean to set timeok = 0 in onmenter()?

There are two methods in jquery for your problem:
.mouseenter() and .mouseleave()
Check out the demos there.
EDIT:
I thought hover was for mouseover and mouseout, sorry for confusion.
I checked your code again. And it seems that you're changing the image when mouse gets over the image, which forces browser to load the new image and the old image disappears for a very little while till the new one appears and i think this must be triggering both handlers continuosly and you're getting this behaviour.
Try not to change the source of the image, comment out that line and instead console.log("some message") there and see if the message is repeated as much as .load() was fired before.
Hope this helps.

Try changing onmleave function as follows:
function onmleave()
{
setTimeout(redotimeok, 2000);
leave();
}

Related

Limiting click detection on the page [javascript]

I'm trying to limit the user's ability to click on an object to a certain time limit. I looked around and found that apparently, setTimeout() is the correct function to use for this type of thing. I've applied the function to my code, but its not working. I'm thinking/know now that the problem is that the setTimeout in my code isn't limiting the actual click event, which I need to do. Here is a snippet of my click code:
function clickRun(event) {
var $objectVersion = correspondingObject(event.target.id);
if (isAnyVisible() == false) { // none open
$objectVersion.makeVisible();
} else if (isAnyVisible() && $objectVersion.isVisible()) { //click already open div
$objectVersion.makeInvisible();
} else if (isAnyVisible() && $objectVersion.isVisible()==false) { //different div open
searchAndDestroy();
$objectVersion.delay(600).makeVisible();
};
};
$('.ChartLink').click(function(event) {
setTimeout(clickRun(event),5000);
});
I've also created a JSFiddle to represent what I'm talking about: http://jsfiddle.net/FHC7s/
Is there a way to achieve limiting the actual click detection on the page?
I think the easiest way to do it is to keep track of the time of the previous click and if the current click is too soon after that, then don't do anything:
onClick = function(){
if(new Date().getTime() - lastCheck < MIN_CLICK_SPACING) return;
}
Have a look at this JSFiddle, I've set it up so you can have the button disable itself for time duration after detecting a click. Just make sure to remember how your closures are operating with your setTimeouts.
Your code contains an error... your line should be
setTimeout(function(){clickRun(event)},5000);
but even then I don't think that's exactly what you're looking for; that code will "delay" the click by 5 seconds, not actually prevent more clicks. If your true intent is to ignore all clicks after a certain amount of time, then I would go with mowwalker's answer; there's no way to stop the clicks, but you can check to see if you should honor them or not.

How to make the cursor change in d3.js when I want?

This is a question related to Basic Javascript loading message while js processing completes
My main problem is that cursor not is changed before my two functions drawlegend() and display() are called, but changes after everthing has finnished.
With the code as below where the restore of the cursor temporary commented out, I get the hourglass, but after everything has finnished.
How to get my cursor to change to an hourglass before my slow functions are called?
examplefunc()
{
mini.append("text")
.text(series[i].name)
.attr("x",30)
.attr("y",(15+(15*i)))
.attr("stroke",(d3.rgb(192,192,192)))
.attr("fill",(d3.rgb(192,192,192)))
.attr("stroke-width",0)
.style("font-size","12px")
.attr("text-anchor","start")
.attr("id","legend")
.on('mouseup', legendclick);
}
//===== legend clicked
function legendclick()
{
//--- get mouse pos
var origin = d3.mouse(this);
//--- get channel
var ch=Math.floor((origin[1]-4)/15);
//--- toggle active state
if (series[ch].active==true)
series[ch].active=false;
else
series[ch].active=true;
setTimeout(setcursor("wait"),5);
drawlegend();
display();
//setTimeout(setcursor("default"),5); // temp removed to see any result at all
}
//===== set cursor
function setcursor(cursor)
{
d3.select("body").style("cursor", cursor);
}
It is known that executing things in javascript, hangs your application. This means that only the eventual output is displayed on your screen. Thus, when you change the cursor to "wait" and after execution to "cursor", the javascript hasn't changed it, because the ui thread was busy calculating the things in the functions "drawlegend" and "display". However, I think when you execute the "drawlegend" and "display" asynchronous like
setTimeout(function () {
drawLegend();
display();
setcursor("default");
}, 0);
then things should go like you want to.
Let me know if this works for you.
Extra info: on this slideshare (especially slide 5) is explained what your problem is.

force DOM redraw with javascript on demand

The title of the question expresses what I think is the ultimate question behind my particular case.
My case:
Inside a click handler, I want to make an image visible (a 'loading' animation) right before a busy function starts. Then I want to make it invisible again after the function has completed.
Instead of what I expected I realize that the image never becomes visible. I guess that this is due to the browser waiting for the handler to end, before it can do any redrawing (I am sure there are good performance reasons for that).
The code (also in this fiddle: http://jsfiddle.net/JLmh4/2/)
html:
<img id="kitty" src="http://placekitten.com/50/50" style="display:none">
<div>click to see the cat </div>
js:
$(document).ready(function(){
$('#enlace').click(function(){
var kitty = $('#kitty');
kitty.css('display','block');
// see: http://unixpapa.com/js/sleep.html
function sleepStupidly(usec)
{
var endtime= new Date().getTime() + usec;
while (new Date().getTime() < endtime)
;
}
// simulates bussy proccess, calling some function...
sleepStupidly(4000);
// when this triggers the img style do refresh!
// but not before
alert('now you do see it');
kitty.css('display','none');
});
});
I have added the alert call right after the sleepStupidly function to show that in that moment of rest, the browser does redraw, but not before. I innocently expected it to redraw right after setting the 'display' to 'block';
For the record, I have also tried appending html tags, or swapping css classes, instead of the image showing and hiding in this code. Same result.
After all my research I think that what I would need is the ability to force the browser to redraw and stop every other thing until then.
Is it possible? Is it possible in a crossbrowser way? Some plugin I wasn't able to find maybe...?
I thought that maybe something like 'jquery css callback' (as in this question: In JQuery, Is it possible to get callback function after setting new css rule?) would do the trick ... but that doesn't exist.
I have also tried to separte the showing, function call and hiding in different handlers for the same event ... but nothing. Also adding a setTimeout to delay the execution of the function (as recommended here: Force DOM refresh in JavaScript).
Thanks and I hope it also helps others.
javier
EDIT (after setting my preferred answer):
Just to further explain why I selected the window.setTimeout strategy.
In my real use case I have realized that in order to give the browser time enough to redraw the page, I had to give it about 1000 milliseconds (much more than the 50 for the fiddle example). This I believe is due to a deeper DOM tree (in fact, unnecessarily deep).
The setTimeout let approach lets you do that.
Use JQuery show and hide callbacks (or other way to display something like fadeIn/fadeOut).
http://jsfiddle.net/JLmh4/3/
$(document).ready(function () {
$('#enlace').click(function () {
var kitty = $('#kitty');
// see: http://unixpapa.com/js/sleep.html
function sleepStupidly(usec) {
var endtime = new Date().getTime() + usec;
while (new Date().getTime() < endtime);
}
kitty.show(function () {
// simulates bussy proccess, calling some function...
sleepStupidly(4000);
// when this triggers the img style do refresh!
// but not before
alert('now you do see it');
kitty.hide();
});
});
});
Use window.setTimeout() with some short unnoticeable delay to run slow function:
$(document).ready(function() {
$('#enlace').click(function() {
showImage();
window.setTimeout(function() {
sleepStupidly(4000);
alert('now you do see it');
hideImage();
}, 50);
});
});
Live demo
To force redraw, you can use offsetHeight or getComputedStyle().
var foo = window.getComputedStyle(el, null);
or
var bar = el.offsetHeight;
"el" being a DOM element
I do not know if this works in your case (as I have not tested it), but when manipulating CSS with JavaScript/jQuery it is sometimes necessary to force redrawing of a specific element to make changes take effect.
This is done by simply requesting a CSS property.
In your case, I would try putting a kitty.position().left; before the function call prior to messing with setTimeout.
What worked for me is setting the following:
$(element).css('display','none');
After that you can do whatever you want, and eventually you want to do:
$(element).css('display','block');

Flickering mousenter mouseleave with delay, button list

I have made a list(<p>) with buttons. When I move my mouse over them it's a 1,2 sec delay before my textbox are marked with yellow to show where I can write. When I move my mouse away they turn normal(white).
My problem is when I quickly hover my mouse over the buttons back and forth a lot of the textboxes gets marked.
I had hoped the 1,2 sec delay would have worked then but it doesn't. But it works if I move my mouse slowly in and out of the button.
Here is a fiddle to it: http://jsfiddle.net/Pota/Fj6E6/
Here is my JavaScript code
$(function () {
$("p.pRespRoleId").mouseenter(function () {
var timeOut = 1200;
$this = $(this);
$this.data("delay", setTimeout(function () {
mouseInRespRoleId();
}, timeOut)
);
})
.mouseleave(function () {
$this = $(this);
if ($this.next(mouseOutRespRoleId()).is(":visible")) {
clearTimeout($this.data("delay"));
mouseOutRespRoleId();
}
else {
$this.next("p.pRespRoleId").show();
}
});
});
and
function mouseInRespRole()
{
var txtInRespRole = document.getElementById("<%=txtRespRoleName.ClientID %>");
txtInRespRole.style.background = "#FFFF00";
if (document.getElementById('txtRespRoleName').value == '')
{
document.getElementById('txtRespRoleName').innerHTML = txtInRespRole;
return false;
}
}
function mouseOutRespRole()
{
var txtOutRespRole = document.getElementById("<%=txtRespRoleName.ClientID %>");
txtOutRespRole.style.background = "white";
if (document.getElementById('txtRespRoleName').value == '')
{
document.getElementById('txtRespRoleName').innerHTML = txtOutRespRole;
return true;
}
}
Your jsFiddle is surely confusing to me (I am not sure what you are trying to achieve - there is a tangible possibility that you are overcomplicating things). I hope I got your requirement right...
Anyway, I believe your logic was right, but there were some flaws in the implementation. So, here is a modified (and partially corrected) version of your jsFiddle, which does what (I believe) you were trying to achieve.
Your use of '$this.next(mouseOutRespRoleId()).is(":visible")' was sure the most confusing, so I removed it completely. (In case it was fulfilling some other, not obvious purpose, you'll have to provide a more detailed description.)
The main problem was that $this.next(mouseOutRespRoleId()).is(":visible") was never evaluating to true, thus never clearing the timer that called mouseInRespRoleId().
EDIT:
I updated my jsFiddle illustration so that it takes care of IE9's strange behaviour (a.k.a. bug (?)). It should work without flickering now.
Short explanation of the problem:
Aparantly, in IE9 the mouse-events generation has some "timing issues", so that when entering (mouseOver) and leaving (mouseOut) a component multiple times rapidly, sometimes the mouse-events order gets messed up. E.g.:
The following event sequence (i.e. actual events):
mouseOver -> mouseOut -> mouseOver
May produce the following (obviously wrong) javascript-event sequence (i.e. events triggered by JS-engine in IE9):
mouseOver -> mouseOver(!) -> mouseOut(!)
So, I added an extra clearTimeout($this.data("delay")) in the "mouseentered" handler-function, in order to clear any pending scheduled executions of "mouseInRespRoleId".
It does not work perfectly on IE9 (and probably previous versions of IE - not tested), but it is as good as it can get (afaik).
(NOTE: It still works as intended on other (non-buggy) browsers.)

jQuery: Timeout/Delay with a notification function?

I wrote the following simple function that takes two parameters mostly coming from another function returned with json from the server.
var timing = 10000;
function notificationOutput(type, message) {
console.log('output now!');
var note = $('.notification');
note.css('display', 'none');
if ( type == "success" ) { note.removeClass('warning').addClass('success'); }
if ( type == "warning" ) { note.removeClass('success').addClass('warning'); }
note.find('.message').html(message);
note.slideDown( function() {
note.delay(timing).slideUp();
});
}
All it does is simply sliding down a bar from the top of my page putting out a message (either success or warning). The timing variable is for the notification-bar to stay for 10 seconds. So when the function is triggered I want the bar to slideDown(), hold that position for 10seconds and than slideUp() again.
However right now when the function is triggered there is a weird timeout happening till the notification bar appears. That means when the function is fired the console.log() output I have in there right now is logged immediately in my JS-console but the slideDown() takes a few seconds longer to appear! Why is that?
I want the slideDown() to happen immediately (at the same time as the output now is logged in the console). Why is there a delay happening?
Thanks for your help!
Nothing obvious there. I would try trimming the code down until it slides down as expected. Remove the callback, remove the html-set, remove the success/warning class-setters, select the note-element before outputting to the console, replace the slide with an immediate show, etc.
Also try calling .stop(true,true) on the note first: note.stop(true,true).slideDown();. This is in case it is busy with some other animation and the slide down is being queued.
Try this
note.slideDown().delay(timing).slideUp();
i think that the problem might be in the easing function used by the slideDown which is swing by default (which is logaritmic). try using linear and maybe try using a faster slidedown time
note.slideDown(400, 'linear').delay(timing).slideUp(400, 'linear');
You are not passing a value for duration to slideDown. Try:
note.slideDown(1000, function() {
note.delay(timing).slideUp();
});

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