Forcing page to refresh after its content has changed - javascript

I have a button which acts as an indicator, so has two states; pressing it toggles the state, and moves on to the next page.
Pressing the button calls a JavaScript function which handles this.
Having changed a button's 'src' image, using jQuery, I wish for the user to see the image change, pause for a fraction of a second, and only then see the next page displayed.
I am finding that the image does not visibly change until the JavaScript function returns, but this is after the pause, and after the page change. I.e. the browser does not show the page changes until the button's function has exit.
So I wish to cause the page to repaint in the browser, before the pause.
All the solutions I have tried refresh the page to its state on the server, and any changes I made to it in jQuery are lost.
Is there a way to force the page or button to be repainted, which will honor the changes I made to it in JavaScript/jQuery?

$("#YourButtonWhichTriggersChanges").click(function() {
// page repaint code, image change, etc.
setTimeout(function(){
window.location.reload();
// use window.location.href = "my/new/url.html";
// or window.location.replace("my/new/url.html");
// to change the page instead of just reloading.
}, 1000);
});
Where 1000 is the number of milliseconds you want to wait before refreshing the page.
Edit: I think you want this code instead:
$("#ApproveButton").css('backgroundImage', 'url(\'img/but/proof/ApprovePageButton.png\')');
The extra backslashes are in there to escape out the single quotes in the url parameter.
Another edit: Here's a combination of the two solutions I supplied which should work:
$("#ApproveButton").click(function() {
// actually repaint the button's background image
$(this).css('backgroundImage', 'url(\'img/but/proof/ApprovePageButton.png\')');
// change the page after 1000 milliseconds have gone by.
setTimeout(function(){
window.location.reload();
/* use window.location.href = "my/new/url.html";
* or window.location.replace("my/new/url.html");
* to change the page instead of just reloading.
*/
}, 1000);
});

Related

remove and append iframe when src refreshes

The code below creates a 10 second delay, and then draws the captcha iframe to the page.
<script>
$(document).ready(function() {
$("#contain").delay(10000).queue(function(next) {
$(this).append('<iframe src="captcha.php"></iframe>');
});
});
</script>
<div id="contain"></div>
When the correct captcha is entered, the iframe captcha page refreshes and a new captcha is presented.
What I would like to happen is every time captcha.php is refreshes, I would like the iframe removed from source again, and the then readded again after 10 seconds.
Originally I was just using a switch inside the captcha to toggle the parent iframe for 10 seconds, but that is relatively easy for the user to just set the display without waiting for the timer - so I am seek a better solution.
It seems the best way, if I can manage to get it working, would be to add and remove the iframe with a 10 second delay on the add.

javascript function reloads page upon completion

I have a simple javascript program that runs onclick of an image.
However, whenever I clicked the image, the page reloaded.
After a lot of debugging I found that the page doesn't reload until right as the script completes.
There are several setTimeouts in the code, but I noticed the page was reloading instantly. I even changed these timeouts to 15000 milliseconds, but it still reloads immediately.
I am using jquery, if it makes any difference.
I also want a different result from the program every time you click it, so that each time you click it a different script runs and a some text changes in a specific order. I did this by changing the onclick attribute of the images in each script to the name of the next script, so that script one would switch onclick to script two, and so on. I set a timeout on these switches so that one click doesn't race through every single script. script two isn't running, so that much works.
my code:
function getSounds() {
console.log("script. initiated");
$("#soundwebGetSoundDirections").html("Now, Wait until the file is done downloading and click below again.");
console.log("new message");
$("#soundwebGetSoundA").attr('href',"");
console.log("href eliminated");
setTimeout($("#soundwebGetSoundImg").attr('onclick','findFile()'),2000);
console.log("onclick to findFile()");
}
function findFile(){
console.log("FINDFILE")
$("#soundwebGetSoundDirections").html("Find the file(it's probably in your downloads), copy the path of the file (usually at the top of the file explorer) and paste in it the box below. Then, make sure there is a '/' at the end of the path and type 'Linkiness.txt' (case sensitive, without quotes) at the end. Once you have all that stuff typed, click the icon again.");
console.log("FIND IT, DARN IT!!");
$("#soundwebGetSoundPathInput").css("opacity",1);
console.log("diving into reader");
setTimeout($("#soundwebGetSoundImg").attr('onclick','readFile()'),1000);
}
function readFile(){
console.log("loading...");
$("#soundwebGetSoundDirections").html("loading...");
if(document.getElementById("soundwebGetSoundPathInput").value.length == 0){
setTimeout($("#soundwebGetSoundDirections").html("Please fill in Path!"),1000);
setTimeout(findFile(),2000);
}
}
and the HTML that's linked to,
<a id = "soundwebGetSoundA" href = "https://docs.google.com/feeds/download/documents/export/Export?id=1ynhHZihlL241FNZEar6ibzEdhHcWJ1qXKaxMUKM-DpE&exportFormat=txt">
<img onclick = "getSounds();" class = "soundwebImgResize" src = "https://cdn3.iconfinder.com/data/icons/glypho-music-and-sound/64/music-note-sound-circle-512.png" id = "soundwebGetSoundImg"/>
</a>
Thanks for any help,
Lucas N.
If you don't want clicking the image to cause the anchor tag to load the href, then move the image tag outside of the anchor tag.
You aren't using setTimeout correctly. You should be passing in a function not a statement. So, for example, instead of
setTimeout($("#soundwebGetSoundDirections").html("Please fill in Path!"),1000);
setTimeout(findFile(),2000);
you should use
setTimeout(function () { $("#soundwebGetSoundDirections").html("Please fill in Path!") },1000);
setTimeout(findFile,2000);
I think the same goes for setting the onclick attribute but I've never tried dynamically changing an onclick attribute like that.
Since you're already using jQuery you could try using .on('click'... and .off('click'... if your current setup isn't working.

Browsers back button is causing issues with hidden field

I've run into an interesting issue and I'm not sure how to solve it. I maintain a hidden value on my homepage that tracks the events loaded on the page. The event position gets updated after the page loads. When navigating away from the page and then clicking the browsers back button the previous event number is seen. If I click a link and load the home page directly the event position gets reset (as expected)
My HTML:
<input type="hidden" id="event_num" value="0">
My javascript call to get/set the event_num value:
function getRecentEvents() {
var event_pos = $('#event_num').val();
//console.log("POS: " + event_pos);
$.getJSON("functions/get_events.php", { f: 'get_events', event_pos: event_pos, limit: limit}, function(data) {
if (data.events.length > 0) {
// set the new value
$('#event_num').val(data.events_pos);
}
});
I would expect the hidden field to be 0 every time the page is loaded regardless if the user clicked a link or hit the back button on the browser.
Any idea how I might fix this or is this a known issue?
The page is not loaded again if you click the "back" button, the cached page content is shown. That is, the page as the state of it was the last time you visited it. You could reset the event_num counter on $(document).ready or on a document unload event, then you will get the expected behaviour.

Website: Detect when I arrive somewhere because of History Navigation

I have a page where I show a throbber when I navigate away from the page. Like <a onclick="throbber.show()"> on every link. When I now navigate back in Firefox, the throbber is still shown.
Is there any javascript event that is fired to the arriving webpage when I click back? Or one that is fired just when the webpage is changed to the new one? Or can I make my throbber more intelligent?
Thanks for any input!
put this in your html:
<form name="_browser"><input id="checker" value="1" type="hidden"></form>
and also this javascript:
function cacheCheck()
{
var checker = document.getElementById("checker");
if (checker.value == 2) return true;
checker.value = 2;
checker.defaultValue = 2;
return false;
}
function cacheReload()
{
if (cacheCheck()) location.reload(true);
}
and then call cacheReload when your page loads:
<body onload="cacheReload()">
Dldnh's answer inpired me to do some tests. I suspected that the body.onload() event would be called when going back and forth. So I created a simple testpage and found out that this is true in Firefox 10, IE7, IE 8, IE 9 and Chrome 17. Also jQuery(document).ready() will be called.
The very simple solution for hidind the throbber would therefore be either using
<body onload="hideThrobber()">
or using jQuery ready
jQuery(document).ready(function () {
hideThrobber();
};
to hide the throbber then. I implemented this and it seems to work fine on my page. Would be great if somebody with a similar problem could confirm this.
I also found this interesting Stackoverflow question. While it is a little outdated, the point that calling javascript on navigation back and forth slowing down the page is still true. But I would guess that todays JS-Engines are fast enough so this is not a real issue anymore.
If you can't turn off the throbber from the page you navigate to, there are a few things you can do. The trick is that the page will be left active, so you can start up some things before you leave, in the onclick. They aren't perfect though.
Start a timer. The timer will be running when you return to the page, so the timeout routine will be called, and you can switch the throbber off there.
Problem: if you set the timer interval too small, the timeout routine will be called before the user has actually left the page, and the throbber will stop. Or if you set the interval too large, it will take a while before the timeout routine kicks in after they have returned.
Add an event listener to the body that responds to the mousemove event, so that as soon as the user moves the mouse, the routine that turnes off the throbber will be called.
Problem: if the user clicks the browser's Back button, the mouse will be outside the window when the page is redisplayed, so the throbber will remain visible until the user moves the mouse into the window.
So, take your pick. Or do both. Just remember to clean up afterwards - stop the timer, remove the event listener.

Always up to date content using AJAX

At the moment I am using ajax requests every 10 minutes to update certain content and other time intervals for others.
I do this using jQuery by:
On mouse move, the active page is checked
If the active page has not be updated within the given time interval, the page is updated
I'm doing this because although i want the content to stay up to date, I don't want it to be sending requests in the background (when the user is not using the application). Doing this also means that if the user has not used it for more than the time period, when they start to use it again it will automatically update.
I'm wondering just how efficient this is as whenever the mouse moves the checks are called (and has slowed down performance a bit - especially when trying to click links) - is the a more efficient way to do this?
Thanks!
I would rather activate/reset a timer, on say, 60 seconds, on movement of the mouse, and set your fixed-interval checks to only run if that timer is above zero.
That way, checks aren't made every time the mouse moves, and if the user becomes inactive, update checks stop after 60 seconds.
Another possible solution would be to use the window blur and focus events to determine if the window is active:
var checkForContentUpdates = true;
$(window).focus(function() {
checkForContentUpdates = true;
});
$(window).blur(function() {
checkForContentUpdates = false;
});
Your AJAX routine would then key off of the checkForContentUpdates bool.
I'm sure that there are scenarios where this isn't fool-proof, so you'd likely have to combine this method with other logic.

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