I'm aware that this can be achieved via a Promise but I am struggling to figure out how.
jQuery('.parentDiv').on('click', '.link', function(e) {
jQuery.when(jQuery('.saveBtn').trigger('click', { 'evtData': 'link' })).then(function {
// rest of the logic that should be performed on click of .link
});
});
The click of .saveBtn calls a function named doAjax:
jQuery('.saveBtn').on('click', function() {
doAjax()
});
function doAjax() {
var ajaxCall = jQuery.ajax(ajaxObject);
ajaxCall.done(function(data, status, xhr) {
//some logic go here
});
return ajaxCall;
}
Despite this the logic inside the .then handler is getting executed first i.e before doAjax completes.
I believe I need to change the jQuery.when(jQuery('.saveBtn').trigger('click',{'evtData':'link'})) as it may not be getting the Promise state which it should and immediately getting marked as Resolved thereby executing the callback without waiting?.
I tried return doAjax in .saveBtn but that also did not make a difference.
Ideas please.
The issue is because trigger() is not an async function, so then is called immediately. It would make far more sense to just call doAjax() directly from the click of .link instead of faking DOM events. Try this:
jQuery(function($) {
$('.parentDiv').on('click', '.link', function(e) {
doAjax().then(function {
// rest of the logic that should be performed on click of .link
});
});
$('.saveBtn').on('click', function() {
doAjax()
});
function doAjax() {
var ajaxCall = $.ajax(ajaxObject);
ajaxCall.done(function(data, status, xhr) {
// some logic go here
});
return ajaxCall;
}
});
I have 2 functions: myFunc1 and myFunc2. When myFunc1 is called, a jQuery confirmation Dialog appears. When the user clicks yes, myFunc2 is called, which should show another dialog.
But, despite successfully calling myFunc2, the second dialog never appears.
Here is a fiddle.
function myFunc1() {
dialog().then(function(data) {
if (data == "yes") {
console.log("clicked yes: show another dialog")
myFunc2();
} else {
console.log("clicked no")
}
});
}
function myFunc2() {
dialog();
console.log("myFunc2 is called")
}
function dialog(title) {
var def = $.Deferred();
$("#dialog").dialog({
modal: true,
buttons: {
"Yes": function() {
def.resolve("yes");
$(this).dialog("close");
},
"No": function() {
def.resolve("no");
$(this).dialog("close");
}
}
});
return def.promise();
}
$("button").on("click", myFunc1);
You are resolving the Deffered-Object before you are actually closing the first dialog. So when the then()-callback is hit, the dialog is still open, therefore no new one is created.
Just swap the functions and it should be working.
"Yes": function() {
$(this).dialog("close");
def.resolve("yes");
},
Example
When the Deferred is resolved, any doneCallbacks added by deferred.then() or deferred.done() are called. Callbacks are executed in the order they were added
.resolve()
You're using the same div to create all your dialogs, if you need to have more than one dialog open at once that will be an issue.
// Get a random unique number to use as the dialog id
var guid = Math.floor(Math.random() * 9999999999999) + 1;
// Clone the dialog div and give it a new name
$("#dialog").clone()[0].id = guid;
// Create the dialog with the new unique div
$("#"+guid).dialog({...});
Also,
// Make sure you remove the div after you close it
$(this).dialog("close").remove();
I'm trying to call a function after a popup automatically closes after 1 second.
This is my code:
$timeout(function() {
var closeit = myPopup.close();
closeit.then(function() {
$scope.dosomething();
});
}, 1000);
The dosomething function is never called. I'm new to AngularJS, anyone who can help me with this?
$ionicPopup - $ionicPopup.show(options) documentation:
Returns: object A promise which is resolved when the popup is closed.
Has an additional close function, which can be used to
programmatically close the popup.
var myPopup = show(options); // when you create a popup with $ionicPopup, you get a promise for the close event
myPopup.then(function() { // add a callback to the promise when it's fulfilled - ie the popup was closed
$scope.dosomething();
});
$timeout(function() {
myPopup.close();
}, 1000);
I have two questions about this code. The first is why the modal is not shown before the alert? The second is how can i delay the modal, because the popup is so fast that i can't see nothing in the modal.
$('#myModal').modal('hide');
$(document).ajaxStart(function() {
$('#myModal').modal('show');
}).ajaxStop(function() {
$('#myModal').modal('hide');
//$('#myModal').delay(5000).modal('hide'); does not work
});
$(".generate_report").click(function(event) {
event.preventDefault();
$.post("xls.php", $(".form_report").serialize(), function() {
}).done(function(data) {
alert("should be executed only after modal");
});
});
demo
You can achieve the same with this code:
$(".generate_report").click(function (event) {
event.preventDefault();
$('#myModal').modal('show');
setTimeout(function(){
$.post("xls.php", $(".form_report").serialize(),function(data){
$('#myModal').modal('hide');
alert("after modal");
})
}, 2000);
});
And remove this code
$(document).ajaxStart(function() {
$('#myModal').modal('show');
}).ajaxStop(function() {
$('#myModal').modal('hide');
//$('#myModal').delay(5000).modal('hide'); does not work
});
What this code does is show a modal when the ajax call starts and instantly hide it when its done. You can use a timer to wait a while before closing it.
Also you've nested a callback function in your jQuery.post, but you don't use it which causes confusing code here. Theres no need to use .done() when you're just going to append it to the AJAX function directly. You can just use the callback function here.
$.post("xls.php", $(".form_report").serialize(), function(data) {
alert("should be executed only after modal");
});
But that is just a code styling concern. The done(), success(), fail() methods are used on a jQuery.Deferred promise object, which $.ajax happens to return. And since $.post/$.get are just pointers to $.ajax, they will too.
Secondly, if you want the modal to wait before it closes, you can do this:
var waitTimer;
var timeToWait = 2000; // Time to wait here
var $myModal = $('#myModal');
$myModal.modal('hide');
$(document).ajaxStart(function() {
$myModal.modal('show');
}).ajaxStop(function() {
if (waitTimer) {
clearTimeout(waitTimer);
}
waitTimer = setTimeout(function() {
$myModal.modal('hide');
}, msToWait);
});
The .delay() method you tried to use only works after you've animated something.
Also a quick tip: Cache your jQuery selectors. You're telling jQuery to jump in the DOM 3 times to search for the same element.
Currently, I'm working to replace "alert'/"confirm" with the jquery dialog.
But most of legacy codes is written in some asynchronous way, which make it difficult to change. Is there any way to make jquery dialog work in a synchronous way? ( don't use loop or callback function )
For example:
function run()
{
var result = confirm("yes or no");
alert( result );
\\more codes here
}
In this example the alert and other codes will be executed after user's choice.
If we use jquery dialog
var result = $dialog.open()
It will continue to execute the alert, which is asynchronous.
Currently, my solution is to use call back function in the OK|Cancel function.
For example:
OK: function ()
{
$dialog.close();
alert("yes");
//more codes here
}
This method works but it is difficult to make all the synchronous codes become asynchronous, which requires a lot of change (see the following example). So I'm looking for the synchronous jQuery Dialog, is it possible??
For example: ( The real codes are much more complicated than the following example)
function f1()
{
if ( confirm("hello") ) f2();
alert("no");
}
function f2()
{
if( confirm("world") ) f3();
alert("no");
}
function f3()
{
return confirm("!") ;
}
Another example:
vendorObject.on('some-event', function() {
if(confirm("Do you really want to do that?")) {
return true;
}
else {
return false; // cancel the event
}
});
... here the vendor object fires an event, which has to be cancelled if the user confirms. The event can only be cancelled if the event handler returns false - synchronously.
The short answer is no, you won't be able to keep your code synchronous. Here's why:
In order for this to be synchronous, the currently executing script would have to wait for the user to provide input, and then continue.
While there is a currently executing script, the user is unable to interact with the UI. In fact, the UI doesn't even update until after the script is done executing.
If the script can't continue until the user provides input, and the user can't provide input until the script is finished, the closest you'll ever get is a hung browser.
To illustrate this behavior, debug your code and set a break point on the line following a line that changes the UI:
$("body").css("backgroundColor", "red");
var x = 1; // break on this line
Notice that your page background is not yet red. It won't change to red until you resume execution and the script finishes executing. You are also unable to click any links in your page while you've got script execution paused with your debugger.
There is an exception to this rule for alert() and confirm(). These are browser controls, and are treated differently than actual web page UI elements.
The good news is that it really shouldn't be very hard to convert your code. Presumably, your code currently looks something like this:
if (confirm("continue?")) {
// several lines of code if yes
}
else {
// several lines of code if no
}
// several lines of code finally
Your asynchronous version could create a function ifConfirm(text, yesFn, noFn, finallyFn) and your code would look very much the same:
ifConfirm("continue?", function () {
// several lines of code if yes
},
function () {
// several lines of code if no
},
function () {
// several lines of code finally
});
Edit: In response to the additional example you added to your question, unfortunately that code will need to be refactored. It is simply not possible to have synchronous custom confirmation dialogs. To use a custom confirmation dialog in the scenario where an event needs to either continue or cancel, you'll just have to always cancel the event and mimic the event in the yesFn callback.
For example, a link:
$("a[href]").click(function (e) {
e.preventDefault();
var link = this.href;
ifConfirm("Are you sure you want to leave this awesome page?", function () {
location.href = link;
});
});
Or, a form:
$("form").submit(function (e) {
e.preventDefault();
var form = this;
ifConfirm("Are you sure you're ready to submit this form?", function () {
form.submit();
});
});
I'm not exactly sure what the motivation behind not using callbacks is so it is hard to judge what solution might satisfy your requirements, but another way to delay execution is through jQuery's "deferred" object.
http://api.jquery.com/category/deferred-object/
You could set up a function that opens the jquery dialog and add code that "waits" for dialog to close. This ends up working in a fairly similar way to a callback in the case you've laid out but here is an example:
function confirm () {
var defer = $.Deferred();
$('<div>Do you want to continue?</div>').dialog({
autoOpen: true,
close: function () {
$(this).dialog('destroy');
},
position: ['left', 'top'],
title: 'Continue?',
buttons: {
"Yes": function() {
defer.resolve("yes"); //on Yes click, end deferred state successfully with yes value
$( this ).dialog( "close" );
},
"No": function() {
defer.resolve("no"); //on No click end deferred successfully with no value
$( this ).dialog( "close" );
}
}
});
return defer.promise(); //important to return the deferred promise
}
$(document).ready(function () {
$('#prod_btn').click(function () {
confirm().then(function (answer) {//then will run if Yes or No is clicked
alert('run all my code on ' + answer);
});
});
});
Here it is working in jsFiddle: http://jsfiddle.net/FJMuJ/
No, you can't do anything sync in Javascript (alert is breaking the rules, in fact). Javascript is built with "single threaded, async" in the core.
What you can do, though, is disable functionality of the underlying page (lightbox-like) so no event get triggered from the page until you don't take the dialog action, be it OK or Cancel. Thought this does not help you to get your sync code working. You have to rewrite.
Here's some ideas - what you actually want is to block your async event to make it look like sync. Here's some links:
Queuing async calls
Mobl
Narrative JavaScript
Hope this helps you further!!
To answer David Whiteman's more specific question, here's how I'm implementing a "deferred" postback for a LinkButton Click event. Basically, I'm just preventing the default behaviour and firing the postback manually when user feedback is available.
function MyClientClickHandler(event, confirmationMessage, yesText, noText) {
// My LinkButtons are created dynamically, so I compute the caller's ID
var elementName = event.srcElement.id.replace(/_/g, '$');
// I don't want the event to be fired immediately because I want to add a parameter based on user's input
event.preventDefault();
$('<p>' + confirmationMessage + '</p>').dialog({
buttons: [
{
text: yesText,
click: function () {
$(this).dialog("close");
// Now I'm ready to fire the postback
__doPostBack(elementName, 'Y');
}
},
{
text: noText,
click: function () {
$(this).dialog("close");
// In my case, I need a postback when the user presses "no" as well
__doPostBack(elementName, 'N');
}
}
]
});
}
You can use a real modal dialog.
[dialog] is an element for a popup box in a web page, including a modal option which will make the rest of the page inert during use. This could be useful to block a user's interaction until they give you a response, or to confirm an action.
https://github.com/GoogleChrome/dialog-polyfill
I don't really see why you are opposed to using Jquery callbacks to achieve the behavior in your example. You will definitely have to rewrite some code but something like:
function f1() {
$( "#testdiv" ).dialog({
modal: true,
buttons: {
"OK": function() {
$( this ).dialog( "close" );
f2();
},
Cancel: function() {
$( this ).dialog( "close" );
alert('no');
}
}
});
}
function f2() {
$( "#testdiv2" ).dialog({
modal: true,
buttons: {
"OK": function() {
$( this ).dialog( "close" );
f3();
},
Cancel: function() {
$( this ).dialog( "close" );
alert('no');
}
}
});
}
function f3() {
$( "#testdiv3" ).dialog({
modal: true,
buttons: {
"OK": function() {
$( this ).dialog( "close" );
},
Cancel: function() {
$( this ).dialog( "close" );
}
}
});
}
<div id="testdiv" title="Hello"/>
<div id="testdiv2" title="World"/>
<div id="testdiv3" title="!"/>