I am trying to create a dynamic hyperlink that will download an image retrieved from the server.
The code I am using:
HTML:
<a class="btn" id="controlDownloadJPEG" download>Save & Download</a>
JS:
this.downloadJPEGClickHandler = function() {
CollageCore.downloadJPEG(function(data){
$("#controlDownloadJPEG").attr("href", "../file/fileStore.action?fileName=/" + data[0].AttachmentUrl);
});;
return true;
};
The href is getting changed on click, but the link itself is linking to the href set before my JavaScript executes. The first click does nothing as there is no default href and the second click will download what the first click should have downloaded.
I have seen suggestions to use JavaScript window.href instead of relying on the html tag itself. The reason I need to use the html tag is for its download functionality.
You are treating an asynchronous call as it it is synchronous. It is like ordering a delivery pizza and expecting it to be there as soon as you place the order. That does not happen unless you are standing in the restaurant and it is already been made.
You need to cancel the click and fire the page change manually when the call comes back. So you want to use window.location.href = "new path"; instead of setting the href.
this.downloadJPEGClickHandler = function() {
CollageCore.downloadJPEG(function(data){
window.location.href = "../file/fileStore.action?fileName=/" + data[0].AttachmentUrl;
});
return false; //or preventDefault if you pass in event object
};
If you are are attaching this activity to an onClick(event) handler you should be able to stop the redirect by passing in event.preventDefault();
cite: http://api.jquery.com/event.preventdefault/
Prevent the default click behavior, change the href attribute, and then imitate the click. Should work.
$( "a" ).click(function( event ) {
event.preventDefault();
$("#controlDownloadJPEG").attr("href", "../file/fileStore.action?fileName=/" + data[0].AttachmentUrl);
$(this).click();
});
Related
I have an application where some actions are taking place on click event of buttons. Also, I want to append a query string on every in the app. For this, I have written a jquery code, which is as follows:-
window.addEventListener('click', function(event) {
event.preventDefault();
var href = event.target.getAttribute("href");
if(href && href.indexOf('http') !== -1) {
timezone = jstz.determine()
window.location.href = href + '?jstz=' + timezone.name();
}
else
{
// re-enable default;
}
}, false);
The code prevents the default action of every click event. Then checks if the event generator has href attribute. If it has href attribute, then it appends the current client timezone in the url.
The problem is, the above code prevents the click event of every clickable object.
How can I re-enable the default action?
Is there any way by which I can use event.preventDefault() for only anchor tags?
You can implement you logic with event listener on a jquery selector as:
$("#target").click(function(event) {
event.preventDefault();
var href = event.target.getAttribute("href");
// blah blah
});
This way, for this example, prevent default is called only if the element with id target is clicked.
For more on jquery selectors: https://www.w3schools.com/jquery/jquery_ref_selectors.asp
This question already has answers here:
How do I programmatically click a link with javascript?
(12 answers)
Closed 8 years ago.
I have a question about Javascript event here. I have an <a> tag like this:
<a id='aTag' href='http://example.com'>Click to redirect</a>
Then I call an event like:
<script>
$('#aTag').click();
//or
$('#aTag').trigger('click');
</script>
It does not redirect me to http://example.com. I tried to add an onClick() event in the <a> tag like this:
<a id='aTag' href='http://example.com' onclick='alert("Event happened");'>Click to redirect</a>
And then call the .click() event. It shows me alert("Event happened");
Can anyone show me how to call the .click() event correctly, or correct this redirect with issue with the href in that <a> tag?
In my business I just need an <a> tag, so not with the window.open or windown.location.
Explanation
Redirects can only happen if the user clicks directly on the link. Programmatic or deferred click triggers do not work.
An alternative would be:
to change directly the window.location
to open the link in a new tab/window
Changing window.location
window.location="http://wherever.you/want/to/g0";
or
window.location=$('a.selector').attr('href'); // to use a link's address
New tab/window
You cannot programmatically (click() or trigger) open new tabs/ windows or redirect. They get (ad-)blocked. automatically
So new tab/window openings always have to be triggered by user action. (Otherwise we'd always be full with popup ads)
So 1st of all, make sure that your js is executed on a user event, and then you should be able to use window.open.
JsFiddle example
html:
new tab google
<button class="user">user triggered</button>
<button class="programatic">programatic</button>
js:
$('a').on('click', function(e) {
console.log('clicked', e);
// unfortunately although we simulated
// the click on the <a/> , it will still
// not launch a new window - idk why.
// therefore we can use the line below
// to open the <a>'s href in a new tab/window
// NOTE: this will only occur if the execution was
// triggered by the user
window.open(e.currentTarget.href);
});
var simulateClick = function(origEv) {
var e = $.Event("click");
e.ctrlKey = true;
e.metaKey = true;
e.originalEvent = origEv;
$('a').trigger(e);
};
$('button.user').on('click', function(e) {
// this call will actually open a window
simulateClick(e);
});
$('button.programatic').on('click', function(e) {
// this will result in a blocked popup
$.get('/someurl').always(function() {
// executes the method after a non-user event
// results in blocked popup
simulateClick(e);
});
});
// this will result in a blocked popup
setTimeout(simulateClick, 1000);
Try this -
<a id="aTag" href="http://mylink.com" onclick="return doWork();">Click to redirect</a>
<script>
function doWork(){
//... do your works
return true; // then return true to redirect
}
</script>
Here is the fiddle - http://jsfiddle.net/gcJ73/
(Though the fiddle attributes are a little different to show you that it works)
or with jQuery:
//first assign the click handler
$('#aTag').click(function(){
//... do your work
return true;
});
//then call programmatically
$("#aTag").click(); or $("#aTag").trigger("click");
BTW programatically calling it will not redirect. Will just call the event handler, not redirect.
jQuery fiddle - http://jsfiddle.net/gcJ73/3/
Try:
<script>
jQuery('#aTag').click(function() {
// Your Code
});
</script>
jQuery('#aTag').click() does not execute the href attribute of an anchor tag so you will not be redirected, do:
$(document).ready(function() {
jQuery('#aTag').click( function (e) {
window.location.href = this.href;
});
});
<a id='aTag' href='http://mylink.com' onclick="location.href='http://mylink.com';">
Click to redirect
</a>
check this code snippet, also it will work like what you want to do.
I have a code similar to this:
<a href='link.html'>goto link page <img src='images/edit.gif' alt='Dont Go, just edit' onclick='doEdit()'></a>
Now I want the href link to work as normal if you click on the text, but if you click on the image, it should do something else and not goto the link at all.
There is also a restriction, I cannot edit the link or its text, the only thing that I have total control over is the img tag and its called onclick function. So I have to prevent the link from going on from within that img tag.
Any help will be appreciated.
Just preventDefault on the click event when the target is an <img>
yourAnchor.addEventListener('click', function (e) {
if (e.target.tagName === 'IMG')
e.preventDefault();
});
Now I want the href link to work as normal if you click on the text, but if you click on the image, it should do something else and not goto the link at all.
The correct way to do that is to not put the img inside the link.
However, if you really want to do that, change your onclick to:
onclick='doEdit(event)'
...and in doEdit:
function doEdit(event) {
if (event.stopPropagation) {
event.stopPropagation(); // Standard
}
else {
event.cancelBubble = true; // Old IE
}
// ...your img logic...
}
That will prevent the click event from bubbling to the link. You need the test for stopPropagation because IE8 and earlier don't have it (or preventDefault), they use properties instead (cancelBubble = true for stopPropagation and returnValue = false for preventDefault). (We're probably stuck with IE8 at least another year, maybe more, despite XP end-of-life...)
Pass the event through to the doEvent method call, similar to this:
<a href='link.html'>goto link page <img src='images/edit.gif' alt='Dont Go, just edit' onclick='doEdit(event)'></a>
Then you can call event.preventDefault() to cancel the event and do your own thing, similar to this:
function doEdit(event){
// your code here
event.preventDefault();
}
DEMO - Using the event object to cancel the event.
Im not quite sure what you mean but if you want the text to have a link and the image to have a onclick event
text
<a href='link.html'>goto link page</a>
image
<img src='images/edit.gif' alt='Dont Go, just edit' onclick='doEdit()'></img>
My initial thought is to simply remove the image tag from between the link tags.
<a href='link.html'>goto link page</a>
<img src='images/edit.gif' alt='Dont Go, just edit' onclick='doEdit()'/>
Are there more restrictions that do not allow you to do something like this?
I just want to enable / disable onclick and href on elements (a or div).
I don't know how to do this.
I can disable onclick by adding an handler on click event, but the href is still available.
$(this).unbind().click(function(event){
event.preventDefault();
return;
});
Edit FOUND A HACK FOR A ELEMENTS
if ($(this).attr("href")) {
$(this).attr("x-href", $(this).attr("href"));
$(this).removeAttr("href");
}
If you return false on the onclick event, the href is irgnored.
This will go to Goole: <a
href="http://www.google.com"
onclick="alert('Go to
Google')">Test</a>
This will not go to Google: Test
Ok i've found a workaround : putting an overlay over the main div containing all the elements i wanted to disable ..
It just works.
You could try the following:
$('a, div').click(
function(e){
return false;
// cancels default action *and* stops propagation
// or e.preventDefault;
// cancels default action without stopping propagation
});
MDC documentation for preventDefault, jQuery documentation for event.preventDefault.
SO question: JavaScript event.preventDefault vs return false.
I'm unsure as to the problem of the "href still being available," since the click event is cancelled; however if you want to remove the href from a elements:
$('a[href]').attr('href','#');
will remove them (or, rather, replace the URL with a #).
Edited in response to comment (to question) by OP:
Ok, sorry ;) I just want to be able (by clicking on a button), to disable / enable all the links (click or href) over elements (div or a)
$('#buttonRemoveClickId, .buttonClassName').click(
function() {
$('a, div').unbind('click');
});
$('#buttonReplaceClickId, .buttonOtherClassName').click(
function() {
$('a, div').bind('click');
});
unbind(),
bind().
Try this to disable click:
$(this).unbind('click');
You can set the href attribute directly to "" to prevent the original from showing up in the status bar, if that's what you're asking.
$(this).unbind().click(function(event){
event.preventDefault();
}).attr("href", "");
Otherwise, a event.preventDefault() already stops links from being clickable.
Suppose we have the ff. in a.html:
<script>
function onClick() {
// Do some important stuff and then...
location = "b.html";
}
</script>
Link
Double-clicking on Link will trigger the event-handler onClick. However, the second click in the double-click seems to be interpreted as another click and causes the page to jump to the named anchor. In effect, the location isn't changed.
My questions are:
Is this a browser bug or feature?
Is there a way to work-around this behavior?
You could try
href="javascript:void(0);"
instead
Use window.location = "b.html". location by itself has no special meaning.
The anchor jumping is unrelated. You can disable it by stopping the event.
function onClick(event) {
event.preventDefault();
event.stopPropagation();
}
Link
gshankar is right
Another variant:
<script>
function onClick() {
location = "b.html";
return false;
}
</script>
Link
Or you can point the link at the function and skip the onclick event:
<script>
function onClick() {
location = "b.html";
return false;
}
</script>
Link