I am using change page event in jquery mobile with multiview plugin when page is change the function calling two times means if am using alert it shows same alert two times and when I click on back button some it shows the page but when I do this frequently it shows error in plug in file can any one help me
Do you mean the pagebeforechange event?
This event is triggering twice as designed.
The difference between this two calls is the data's toPage attribute:
jQuery(document).bind('pagebeforechange', function(e, data) {
var toPage = data.toPage;
if(typeof toPage === 'string') {
// -- triggered first
// -- toPage is a string containing the page`s url
} else {
// -- triggered second
// -- toPage is an jQuery collection object containing the page
}
});
Related
I have 2 Jquery Mobile pages (Login and Home). When the user first launches the application (phonegap) the system check for a local storage variable ('ses_already_login). If the variable is set then the system should not show the login page instead it should show the home page. If the variable is not set then it should show the login page.
Both login and home page contains a header and footer with some form controls which are loaded dynamically using jQuery.
I am doing something like below and I see a blank grey screen. The condition gets through and could see the alert message after that I goes to a blank screen.
$(document).on("pagebeforeshow","#pg_login",function(){
if(checkAlreadyLogin()){
alert('I am inside');
$.mobile.changePage("#pg_home");
e.preventDefault();
}
});
I also aware that changePage is deprecated. So, can someone help me how I can redirect/change to the home page.
Solution 1:
You need to use pagecontainerbeforechange in that case not any other event. Because at this stage, you can alter toPage property to redirect user to any page you want.
That event always fires twice and returns toPage which holds either url (string) or jQuery object of target page. However, on first run it returns a jQuery object twice. When it fires for the first time, you have to make sure that toPage is an object and absUrl is undefined, in addition to your condition.
$(document).on("pagecontainerbeforechange", function(e, data) {
if(typeof data.toPage == "object" && typeof data.absUrl == "undefined" && !condition) {
data.toPage = $("#login"); /* change to page with ID "login" */
}
});
Demo
Solution 2:
Another solution is to listen to mobileinit event to check whether user is logged in or not, and then change the position of target page to make "first" page in DOM.
$(document).on("mobileinit", function (e, data) {
$.mobile.autoInitializePage = false; /* optional - stop auto-initalization */
if (!condition) {
$(function () {
$("#login").prependTo("body"); /* make "login" page first child of "pagecontainer" (body by default) */
$.mobile.initializePage(); /* optional - manual initialization */
});
}
});
You can delay auto-initialization of the framework if you want, however, jQuery functions .prependTo should be wrapped in $(function() {}); or .ready() because mobileinit fires before jQuery library is ready.
Demo
I'm writing my own ESC handler because I need to do other actions when ESC is pressed, specifically I need to manage where focus goes for keyboard-only users. I have it working for all menus and some dialogs (both of which are using jQueryUI) but I'm having problems with dialogs that open on top of other dialogs (confirmation dialogs).
I'm using a Backbone View and adding my keydown handler on dialogcreate. this.$el.on('dialogcreate', this.bindKeydownEvent);
My handler:
bindKeydownEvent: function(ev, ui) {
var self = this;
this.$el.dialog().on('keydown', function(evt) {
if(evt.keyCode === $.ui.keyCode.ESCAPE) {
self.$el.dialog("close");
if(self.options.closeFocusEl) {
$(self.options.closeFocusEl).focus();
}
evt.stopPropagation();
}
});
}
I've checked and this.$el.dialog() is the correct dialog when the second dialog calls this.bindKeydownEvent but for some reason the keydown handler is not being triggered no matter what I press in the dialog (Tab, Space, Enter, random letters, etc).
Any idea what I'm doing wrong or have a better way I could bind the keydown event?
EDIT:
I just noticed that this is also happening in some first-level dialogs. It looks like the only difference is the way we get the template and therefore create the interior of the dialog. In our Alert and Confirmation dialog classes, we define the template as an attribute on the object like this: template: _.template("<div><%= o.content %></div>"). In other views (in which the keydown binding works) we build the child elements and add them to the DOM of the dialog, set the template in the initialize function
this.options.template = 'navigation/CreateNewDialog.template';
or set it when we call the dialog
var closeConv = new views.CloseConversationDialogView({
confirm: this.closeConversationConfirmed,
content: i18n.t("closeConversationInput"),
template: "conversation/CloseConversationDialog.template"
});
closeConv.render();
Is there a reason that creating the template inline as an attribute on the view would not bind keydown correctly?
To understand why your event handler isn't being triggered you need first understand how event delegation works.
The key to event delegation in that events bubble up the DOM. So when you bind your event using this.$el.dialog().on('keydown',..., what you basically doing is listening to any keydown event that is triggered on your $el or it's descendants. In this case being that your second dialog isn't a descendant of your $el it's events won't bubble up to it and therefore don't trigger your handler.
To work around this you can either bind directly to your second dialog, or instead bind to a exisitng higher level element like the document. For example
$(document).on('keydown', '.myDialog', function() {...
The only thing my original attempt was missing was "widget". The widget method, according to api.jqueryui.com,
Returns a jQuery object containing the generated wrapper.
I don't see any documentation on what exactly $('.selector').dialog() returns but apparently it is not the same as $('.selector').dialog("widget"). I also changed on('keydown'... to just use the jQuery keydown instead.
bindKeydownEvent: function(ev, ui) {
var self = this;
this.$el.dialog("widget").keydown(function(evt) {
if(evt.keyCode === $.ui.keyCode.ESCAPE) {
self.$el.dialog("close");
if(self.options.closeFocusEl) {
$(self.options.closeFocusEl).focus();
}
evt.stopPropagation();
}
});
}
I have the following:
$(document).on("pageinit", function (event) {
alert("pageinit called");
$('#logout').bind('click', function() {alert("clicked!");});
});
The first time the page runs you get a single alert 'pageinit called'. Clicking the element with id #logout fires the alert 'clicked!'. If I click any other links in this page I still get the 'pageinit called' alert (and I get it multiple times, apparently for each page I have previously navigated as well) but subsequently the handler for #logout is gone and never never re-established.
Can anyone tell me how I can get the handler for #logout to remain? I've tried:
$('#logout').die('click').live('click', function() {alert("clicked!");});
to no avail.
After looking more closely (and as commented by Omar), this problem is caused by a combination of the jquery mobile paging system AND trying to attach to a 'single' element by id.
In my case each time I clicked a link within the page it would load into the jqm paging system a separate page, each one containing its own #logout element. My solution was to query for all the buttons and attach handlers to each one:
var buttons = $("*[id='logout']");
buttons.each(function() {
// handle click or whatever here
});
Instead of:
var button = $('#logout'); // Only hooks into the first #logout element
Adding my bindings to the pageinit event like so:
$('#mypage').on("pageinit", function () {
$('#login-sumbit').on('click', function () {
console.log('button clicked');
});
});
I would expect pageinit to bind the click event once only. But what happens in my single page app is that the button is binding every time the page is loaded even when clicking back.
This results in undesirable multiple duplicate binds. Any ideas on what event to use to bind only once in my single page app, so that loading the page again (back button, loading inline page) in the same session doesn't re-bind?
Looks like I found the answer myself, turns out quite rightly pageinit fires every time the page is loaded even though it's not reloading from the server, otherwise what would fire when a new page is shown.
pageinit is the right event but I need to use .one not .on, .one will bind one time only.
$('#mypage').on("pageinit", function () {
$('#login-sumbit').one('click', function () {
console.log('button clicked');
});
});
Now everything works as expected. Better still I've found you can use .one with the pageinit event for even more control over your bindings and data loads perfect for my requirements.
http://api.jquery.com/one/
You could use:
$('#login-sumbit').off('click').on('click', function(e) {
console.log('button clicked');
});
I'm trying to dynamically populate a select tag at load time (latest jQM version) using a custom template filling function.
If the fn is called in the "pagebeforechange" event, the select tag is properly initialized. Since this event is called on every page transition, I thought of moving the fn to the 'pageinit' event. This does not work, presumably because the DOM is not yet fully available. How can I coerce jQM to inject content in a page only once? Currently, I am using a kludge. There surely must be a smarter way. Thanks for any suggestions.
$(document).bind('pageinit', function () {
InitSelTagTest("#selActTag", "tplTag"); // Does not work.
});
$(document).bind("pagebeforechange", function (e, data) {
if ($("#selActTag").children().size() === 0) {
InitSelTagTest("#selActTag", "tplTag"); // Kludge, but it works
}
});
function InitSelTagTest(el,tpl) { // Append all tags to element el
var lstAllTags = JSON.parse($("#hidTag").val()); // Create tag array
// Retrieve html content from template.
var cbeg = "//<![" + "CDATA[", cend = "//]" + "]>";
var rslt = tmpl(tpl, { ddd: lstAllTags }).replace(cbeg, ").replace(cend,");
$(el).html(rslt).trigger("create"); // Add to DOM.
}
EDIT
In response to Shenaniganz' comment, it seems that the "pagebeforecreate" event could do the trick ie.
$("#pgAct").live("pagebeforecreate", function () {
// Populate tag select. Works. Traversed only once.
InitSelTag("#selActTag", "tplTag");
});
I'm not sure I fully understand your question but I'll throw a few things out there and you let me know if I can extend further.
To make something trigger only once on page load you can try to implement a regular JQuery $(document).ready(function(){}) aka $(function(){}) for the exact reason why JQuery Mobile users are told not to use it. It triggers only once on DOM load. Further pages don't trigger it because they're being switched via Ajax.
Other than that, on regular dynamic content loading you take a look at the following example I put together for someone else earlier:
http://jsbin.com/ozejif/1/edit