I can not seem to find the code to disable a javascript function. What I want to do is have a javascript function and then I want to disable it. Here is the code:
<script>
var fooFunc = function fooFunction() {
alert("HELLO");
};
$(document).ready(function() {
fooFunc.disable();
});
</script>
<button onclick="fooFunc()">Button</button>
Basically, when the button is click the function should not work, it should be disabled. Thanks
"Disabling" fooFunc is the same as setting it to an empty function (not to null--that will cause an error when it is called the next time). In this case:
$(document).ready(function() {
fooFunc = function() { };
});
But I don't see how this is different from simply removing the onclick handler from the HTML element.
If you want the ability to disable/re-enable the function, you can write it like this:
fooFunc = function() {
function _fooFunc() {
if (!enabled) return;
alert("HELLO");
}
var enabled = true;
_fooFunc.enable = function() { enabled = true; };
_fooFunc.disable = function() { enabled = false; };
return _fooFunc;
}();
If you want to extend this to allow any function to be enabled/disabled, you can write a higher-order function, which takes any function as a parameter, and returns a function with enable and disable methods attached to it:
function disablable(fn) {
function inner() {
if (!enabled) return;
fn();
}
var enabled = true;
inner.enable = function() { enabled = true; };
inner.disable = function() { enabled = false; };
return inner;
}
Now you can define fooFunc as
var fooFunc = disablable(function fooFunction() {
alert("HELLO");
});
and the rest of your code will work as you want.
You can access the onclick property of the element..
<button id="id" onclick="fooFunc()">Button</button>
<script>
document.querySelector('#id').onclick = '';
</script>
If you don't want the function to work at all and be totally disabled then use the below.
If you want the function to work only under certain conditions then you will need if/else statements so it will work only when the conditions that you have set are met.
$(document).ready(function(){
$("button").onclick(function(event){
event.preventDefault();
});
});
You were going to define it back to undefined or null.
fooFunc=undefined;
You Should be doing this :) Change function definition on very first run and you are good to go.
<! DOCTYPE html>
<html lang="en">
<body>
<script>
var fooFunc = function() {
alert("HELLO");
fooFunc = function(){};
};
var enablefooFunc = function()
{
fooFunc = function() {
alert("HELLO");
fooFunc = function(){};
};
}
</script>
<button onclick="fooFunc()">Run once and Disable FooFunc</button>
<button onclick="enablefooFunc()">Enable FooFunc</button>
</body>
</html>
Related
I have this JS function which I'm trying to toggle on and off when clicked on the object with the myFunc() function on it. The trouble I'm having is that by the time the code reaches the first if(myVar)/else part and tries to do the handler it has already switched the myVar variable to false. What should I change to correct my logic error?
<script type="text/javascript">
var myVar = true;
function myFunc(myElement) {
var ele = myElement;
var myHandler = function(event) {
if(myVar) {
// do something
} else {
// do something else
}
}
if(myVar) {
window.addEventListener('mousemove', myHandler, false);
myVar = false;
} else {
window.removeEventListener('mousemove', myHandler, false);
myVar = true;
}
}
</script>
...
<body>
<div id="div1" onclick="myFunc(this)"></div>
</body>
I think this is what you are looking for:
var myVar = false;
function myHandler(event) {
if (myVar) {
console.log('do something');
}
}
function myFunc(myElement) {
var ele = myElement;
myVar = !myVar;
if (myVar) {
window.addEventListener('mousemove', myHandler, false);
} else {
window.removeEventListener('mousemove', myHandler, false);
}
}
<button onclick="myFunc(this)">click me</button>
Tell me if there is something you're not understanding in this code.
Why does myHandler need to check the value of myVar? According to your logic, myVar will always be false when myHandler runs, because you're always setting it to false when you add the event listener. myVar will only ever be set to true when you remove the event listener, so myHandler will never run when myVar is true.
You can remove the if(myVar)/else from myHandler since myVar will always be false there.
you can achieve this by 2 methods
method 1:
<body>
<div id="div1">div</div>
</body>
<script type="text/javascript">
var myVar = false;
var myHandler = function() {
myVar = !myVar;
}
document.getElementById('div1').addEventListener('click', myHandler);
</script>
method2:
<body>
<div onClick="myHandler()">div</div>
</body>
<script type="text/javascript">
var myVar = false;
var myHandler = function() {
myVar = !myVar;
}
</script>
hope you have found what you are looking for.
I want to make a button that toggles a new class when it's clicked, then when that new class is clicked, it sets goAway to true. Here's what I'm using, does anyone notice something that would prevent this? It works in all other onclick functions that have the line: goAway = true;
var goAway = false;
$("button:not(.MyNewClass)").click(function(){
window.onbeforeunload = function () {
if (!goAway) {
return 'Syanara mutha ******';
}
}
});
$(document).ready(function() {
$('.MyNewClass').click(function() {
goAway = true;
});
});
I have also tried this below, but neither seem to work...
var goAway = false;
$("button:not(.MyNewClass)").click(function(){
window.onbeforeunload = function () {
if (!goAway) {
return 'Syanara mutha ******';
}
}
});
$(document).ready(function() {
$('.MyNewClass').click(function() {
window.onbeforeunload = null;
});
});
You can try either one of this.
First one:
$(window).unbind('onbeforeunload');
Second one:
window.onbeforeunload = false;
I hope this works for you.
Update:
I noticed you placed onbeforeunload function inside click function.
Once try by placing this function out side of click function.
window.onbeforeunload = function () {
if (!goAway) {
return 'Syanara mutha ******';
}
}
Finally! I figured it out. Attached a JavaScript onClick event to the element set to toggle with jQuery ;)
The html button:
<button onclick="removeWarning()">This is the button</button>
Then the rest:
<script>
var goAway = false;
$("button").click(function(){
$(this).toggleClass('MyNewClass');
window.onbeforeunload = function () {
if (!goAway) {
return 'Syanara mutha ******';
}
}
});
function removeWarning(){
if ($("button").hasClass('MyNewClass')){
goAway = true;
}
}
</script>
I have some variables in the following JS:
document.addEventListener('DOMContentLoaded', function (){
document.getElementById('btn4').addEventListener('click', getbg);
});
getbg = function()
{
chrome.runtime.getBackgroundPage(
function (bg) {
var allcompanynames = bg.companynames;
alert(allcompanynames)})
}
As you can see, the variable is "allcompanynames".
However, how do I pass them and show it on the popup.html page?
I have tried
<script type="text/javascript" src="companynames.js"></script>
<p id="allcompanynames"></p>
no luck. What's wrong?
document.addEventListener('DOMContentLoaded', function (){
document.getElementById('btn4').addEventListener('click', getbg);
});
getbg = function()
{
chrome.runtime.getBackgroundPage(
function (bg) {
var allcompanynames = bg.companynames;
alert(allcompanynames)})
document.getElementById("allcompanynames").innerHTML(allcompanynames)
}
I'm guessing you should add that last line after displaying the pop up to add the content into the page.
Write your code in this way
var background = chrome.extension.getBackgroundPage();
var allcompanynames = background.companynames;
alert(allcompanynames)
I attempted to combine two functions in the code below. All seems to be working except I cannot get the variable currentImage.metaData.something to work in the second function. I appreciate your advice.
<script type="text/javascript" src="code.photoswipe-2.1.5.min.js"></script>
<script type="text/javascript">
(function(window, PhotoSwipe){
document.addEventListener('DOMContentLoaded', function(){
var
options = {
getImageMetaData: function(el){
return {
href: el.getAttribute('href'),
something: el.getAttribute('data-something'),
anotherThing: el.getAttribute('data-another-thing')
}
}
},
instance = PhotoSwipe.attach( window.document.querySelectorAll('#Gallery a'), options );
instance.addEventHandler(PhotoSwipe.EventTypes.onDisplayImage, function(e){
var currentImage = instance.getCurrentImage();
console.log(currentImage.metaData.something);
console.log(currentImage.metaData.anotherThing);
});
}, false);
}(window, window.Code.Util, window.Code.PhotoSwipe));
(function(window, Util, PhotoSwipe){
document.addEventListener('DOMContentLoaded', function(){
var
sayHiEl,
sayHiClickHandler = function(e){
alert('yo!!!');
}
options = {
getToolbar: function(){
return '<div class="ps-toolbar-close" style="padding-top: 12px;">Close</div><div class="ps-toolbar-play" style="padding-top: 12px;">Play</div><div class="ps-toolbar-previous" style="padding-top: 12px;">Previous</div><div class="ps-toolbar-next" style="padding-top: 12px;">Next</div><div class="say-hi" style="padding-top: 12px;">Say Hi!</div>';
// NB. Calling PhotoSwipe.Toolbar.getToolbar() wil return the default toolbar HTML
}
},
instance = PhotoSwipe.attach( window.document.querySelectorAll('#Gallery a'), options );
// onShow - store a reference to our "say hi" button
instance.addEventHandler(PhotoSwipe.EventTypes.onShow, function(e){
sayHiEl = window.document.querySelectorAll('.say-hi')[0];
});
// onToolbarTap - listen out for when the toolbar is tapped
instance.addEventHandler(PhotoSwipe.EventTypes.onToolbarTap, function(e){
if (e.toolbarAction === PhotoSwipe.Toolbar.ToolbarAction.none){
if (e.tapTarget === sayHiEl || Util.DOM.isChildOf(e.tapTarget, sayHiEl)){
alert(currentImage.metaData.anotherThing);
}
}
});
// onBeforeHide - clean up
instance.addEventHandler(PhotoSwipe.EventTypes.onBeforeHide, function(e){
sayHiEl = null;
});
}, false);
}(window, window.Code.Util, window.Code.PhotoSwipe));
You're declaring the currentImage variable within the first function. Variables created with the var keyword are function-scoped, meaning that it isn't visible outside of the function (and hence not visible in your second function, in this case).
I would probably suggest some more general code reorganization, but an easy fix would be to declare the variable above both of your functions, making it visible to both.
Need to apply a var to a statement if its conditions are met, this syntax isn't throwing errors but its not working.
<script type="text/javascript">
$(document).ready(function(){
var action_is_post = false;
//stuff here
$(this).ready(function () {
if ($("#stepDesc0").is(".current")) {
action_is_post = true;
}
});
//stuff here
</script>
should I use something other than .ready? Do I even need the $(this).ready(function ()... part? I need it to apply the var when #stepDesc0 has the class current.
$(document).ready(function(){
var action_is_post = false;
$("form").submit(function () {
action_is_post = true;
});
if ($("#stepDesc0").is(".current")) {
var action_is_post = true;
}
window.onbeforeunload = confirmExit;
function confirmExit()
{
if (!action_is_post)
return 'Using the browsers back, refresh or close button will cause you to lose all form data. Please use the Next and Back buttons on the form.';
}
});
<script type="text/javascript">
$(document).ready(function(){
var action_is_post=$("#stepDesc0").is(".current");
});
</script>
If you want the variable to be accessible outside the $(document).ready(function(){..., then you'll need to declare it outside the statement like this:
<script type="text/javascript">
var action_is_post;
$(document).ready(function(){
action_is_post=$("#stepDesc0").is(".current");
});
</script>
HTML (in order to test it):
Show value
$(function() {
var actionIsPost = $('#stepDesc0').is('.current');
alert( actionIsPost );
});
If you are adding the current class to #stepDesc0 on an event then put the .is check in the event handler.