I am currently working on a dialog in order to replace the browser‘s original alert and confirm dialogs since I do not like them. My dialog is very flexible in it‘s use.
So my function is called msgBox and it has got the following syntax:
msgBox (prompt, title, buttons, modal, gradient)
All params are optional. In that case the function uses default values.
So far it works excellent already. Please see the code below.
I want to achieve now, getting as result the button that is clicked by the user to assign it to a variable or use it in an If-statement.
For example:
let response = msgBox("Load Settings?", "Confirm", ["Yes","No", "Restore defaults"]);
or
if (msgBox("Load file?", "Confirm", ["Yes","No", "Search"]) == 'Yes') {
// do some stuff
}
I want the dialog work this way, that it returns'false' in case it is non-modal and the user clicked on an area outside, otherwise it should return the clicked button as string in order to evaluate it.
Here is the code so far:
let isModal = true;
let msgBoxAnswer = null;
// #####################################################################################
// PURPOSE: Displays a modal | modeless dialog with dynamical buttons
//
// PARAMETER: - prompt = prompt text
// - titel = Titelzeie des Dialogs
// - buttons = Button-Array, sepatated by komma - Default = 'Ok'
// - modal = dialog modal | modeless - default = modal
// - gradient = optional: gradient of the titlebar
// RETURNS: : the value of the clicked button as string
// #####################################################################################
async function asyncMsgBox(prompt, title, buttons = ['Ok'], modal = true, gradient) {
// do some init stuff...
msgBoxAnswer = null;
if (prompt == null) {prompt = ''}
if (title == null || title.trim() == '') {
title = document.getElementsByTagName("title")[0].innerHTML;
}
isModal = modal;
let classnames = 'overlay';
if (modal) { classnames += ' dark'}
// search for the parent container (usually it's the <body>)
let parent = document.getElementsByTagName('body')[0];
parent.innerHTML += `<div id="msgBoxBG" class="${classnames}" onclick="closeDialog('cancel')"></div>`;
// catching an empty button-array
if (buttons[0] == '') {buttons[0] = 'Ok'}
// first create the buttons!
// otherwise the <div> is going to be closed automatically
let btnCode ='';
for (let i = 0; i < buttons.length; i++) {
const btn = buttons[i];
btnCode += `<button class="btnMsgbox" onclick="closeDialog('${btn}')">${btn}</button>`;
}
classnames = 'titlebar';
if (gradient) { classnames += ' gradient'}
let container = $('msgBoxBG');
container.innerHTML = `
<div class="dialog">
<div class ="${classnames}">
<h2 id="msgCaption">${title}</h2>
</div>
<p id="msgPrompt">${prompt}</p>
${btnCode}
</div>`;
try {
// HERE START THE PROBLEMS...
let answer = await closeDialog();
return answer; // resolve()
} catch(err){
return false; // reject()
}
}
function closeDialog(response){
return new Promise(function(resolve, reject) {
if (response) {
if (isModal && response == 'cancel') {return};
if (!isModal && response == 'cancel') {
$('msgBoxBG').remove();
reject('false');
} else if (response !='cancel') {
$('msgBoxBG').remove();
resolve(response);
} else {
return;
}
}
});
}
The problem is, that await closeDialog() finds the response-parameter 'undefined' at the first call and returns before the user is able to click on any button at all, which should call the same function.
I must add that I am not very experienced in Javascript yet. So if anyone has another suggestion or solution how to solve the problem, I am open to learn.
Thanks in advance for your help!
In my project, I've added the alert box and try to close the box if the user clicks on disclose button. But I don't know why this if condition is not executed.
can anyone tells me where I did make a mistake?
window.onload = function(){
var button = document.querySelector(".close");
var successMessage = document.querySelector(".messageStackSuccess");
var messageStack = document.querySelector(".messageStackError");
// console.log(successMessage.className);
button.onclick = function () {
if (messageStack.className == "messageStackError") {
messageStack.classList.add("displayNone");
}
else if (successMessage.className == "messageStackSuccess") {
successMessage.classList.add("displayNone");
}
};
};
I want to check with JavaScript if the user has already opened my website in another tab in their browser.
It seems I cannot do that with pagevisibility...
The only way I see is to use WebSocket based on a session cookie, and check if the client has more than one socket. But by this way, from current tab, I have to ask my server if this user has a tab opened right next to their current browser tab. It is a little far-fetched!
Maybe with localstorage?
The shorter version with localStorage and Storage listener
<script type="text/javascript">
// Broadcast that you're opening a page.
localStorage.openpages = Date.now();
var onLocalStorageEvent = function(e){
if(e.key == "openpages"){
// Listen if anybody else is opening the same page!
localStorage.page_available = Date.now();
}
if(e.key == "page_available"){
alert("One more page already open");
}
};
window.addEventListener('storage', onLocalStorageEvent, false);
</script>
Update:
Works on page crash as well.
Stimulate page crash in chrome: chrome://inducebrowsercrashforrealz
Live demo
Using local storage I created a simple demo that should accomplish what your looking to do. Basically, it simply maintains a count of currently opened windows. When the window is closed the unload events fire and remove it from the total window count.
When you first look at it, you may think there's more going on than there really is. Most of it was a shotty attempt to add logic into who was the "main" window, and who should take over as the "main" window as you closed children. (Hence the setTimeout calls to recheck if it should be promoted to a main window) After some head scratching, I decided it would take too much time to implement and was outside the scope of this question. However, if you have two windows open (Main, and Child) and you close the Main, the child will be promoted to a main.
For the most part you should be able to get the general idea of whats going on and use it for your own implementation.
See it all in action here:
http://jsbin.com/mipanuro/1/edit
Oh yeah, to actually see it in action... Open the link in multiple windows. :)
Update:
I've made the necessary changes to have the the local storage maintain the "main" window. As you close tabs child windows can then become promoted to a main window. There are two ways to control the "main" window state through a parameter passed to the constructor of WindowStateManager. This implementation is much nicer than my previous attempt.
JavaScript:
// noprotect
var statusWindow = document.getElementById('status');
(function (win)
{
//Private variables
var _LOCALSTORAGE_KEY = 'WINDOW_VALIDATION';
var RECHECK_WINDOW_DELAY_MS = 100;
var _initialized = false;
var _isMainWindow = false;
var _unloaded = false;
var _windowArray;
var _windowId;
var _isNewWindowPromotedToMain = false;
var _onWindowUpdated;
function WindowStateManager(isNewWindowPromotedToMain, onWindowUpdated)
{
//this.resetWindows();
_onWindowUpdated = onWindowUpdated;
_isNewWindowPromotedToMain = isNewWindowPromotedToMain;
_windowId = Date.now().toString();
bindUnload();
determineWindowState.call(this);
_initialized = true;
_onWindowUpdated.call(this);
}
//Determine the state of the window
//If its a main or child window
function determineWindowState()
{
var self = this;
var _previousState = _isMainWindow;
_windowArray = localStorage.getItem(_LOCALSTORAGE_KEY);
if (_windowArray === null || _windowArray === "NaN")
{
_windowArray = [];
}
else
{
_windowArray = JSON.parse(_windowArray);
}
if (_initialized)
{
//Determine if this window should be promoted
if (_windowArray.length <= 1 ||
(_isNewWindowPromotedToMain ? _windowArray[_windowArray.length - 1] : _windowArray[0]) === _windowId)
{
_isMainWindow = true;
}
else
{
_isMainWindow = false;
}
}
else
{
if (_windowArray.length === 0)
{
_isMainWindow = true;
_windowArray[0] = _windowId;
localStorage.setItem(_LOCALSTORAGE_KEY, JSON.stringify(_windowArray));
}
else
{
_isMainWindow = false;
_windowArray.push(_windowId);
localStorage.setItem(_LOCALSTORAGE_KEY, JSON.stringify(_windowArray));
}
}
//If the window state has been updated invoke callback
if (_previousState !== _isMainWindow)
{
_onWindowUpdated.call(this);
}
//Perform a recheck of the window on a delay
setTimeout(function()
{
determineWindowState.call(self);
}, RECHECK_WINDOW_DELAY_MS);
}
//Remove the window from the global count
function removeWindow()
{
var __windowArray = JSON.parse(localStorage.getItem(_LOCALSTORAGE_KEY));
for (var i = 0, length = __windowArray.length; i < length; i++)
{
if (__windowArray[i] === _windowId)
{
__windowArray.splice(i, 1);
break;
}
}
//Update the local storage with the new array
localStorage.setItem(_LOCALSTORAGE_KEY, JSON.stringify(__windowArray));
}
//Bind unloading events
function bindUnload()
{
win.addEventListener('beforeunload', function ()
{
if (!_unloaded)
{
removeWindow();
}
});
win.addEventListener('unload', function ()
{
if (!_unloaded)
{
removeWindow();
}
});
}
WindowStateManager.prototype.isMainWindow = function ()
{
return _isMainWindow;
};
WindowStateManager.prototype.resetWindows = function ()
{
localStorage.removeItem(_LOCALSTORAGE_KEY);
};
win.WindowStateManager = WindowStateManager;
})(window);
var WindowStateManager = new WindowStateManager(false, windowUpdated);
function windowUpdated()
{
//"this" is a reference to the WindowStateManager
statusWindow.className = (this.isMainWindow() ? 'main' : 'child');
}
//Resets the count in case something goes wrong in code
//WindowStateManager.resetWindows()
HTML:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>JS Bin</title>
</head>
<body>
<div id='status'>
<span class='mainWindow'>Main Window</span>
<span class='childWindow'>Child Window</span>
</div>
</body>
</html>
CSS:
#status
{
display:table;
width:100%;
height:500px;
border:1px solid black;
}
span
{
vertical-align:middle;
text-align:center;
margin:0 auto;
font-size:50px;
font-family:arial;
color:#ba3fa3;
display:none;
}
#status.main .mainWindow,
#status.child .childWindow
{
display:table-cell;
}
.mainWindow
{
background-color:#22d86e;
}
.childWindow
{
background-color:#70aeff;
}
(2021) You can use BroadcastChannel to communicate between tabs of the same origin.
For example, put the following at the top level of your js code, then test by opening 2 tabs:
const bc = new BroadcastChannel("my-awesome-site");
bc.onmessage = (event) => {
if (event.data === `Am I the first?`) {
bc.postMessage(`No you're not.`);
alert(`Another tab of this site just got opened`);
}
if (event.data === `No you're not.`) {
alert(`An instance of this site is already running`);
}
};
bc.postMessage(`Am I the first?`);
I know it is late, but maybe help someone
This snippet of code, will detect how many tabs are open and how many are active (visible) and if none of tabs is active, it will choose last opened tab, as active one.
This code will handle windows/tab crash too and it will refresh the count at crash.
Because localStorage is not supported on Stack Overflow currently, please test here.
<html>
<body>
Open in several tabs or windows
<div id="holder_element"></div>
<script type="text/javascript">
//localStorage.clear();
manage_crash();
//Create a windows ID for each windows that is oppened
var current_window_id = Date.now() + "";//convert to string
var time_period = 3000;//ms
//Check to see if PageVisibility API is supported or not
var PV_API = page_visibility_API_check();
/************************
** PAGE VISIBILITY API **
*************************/
function page_visibility_API_check ()
{
var page_visibility_API = false;
var visibility_change_handler = false;
if ('hidden' in document)
{
page_visibility_API = 'hidden';
visibility_change_handler = 'visibilitychange';
}
else
{
var prefixes = ['webkit','moz','ms','o'];
//loop over all the known prefixes
for (var i = 0; i < prefixes.length; i++){
if ((prefixes[i] + 'Hidden') in document)
{
page_visibility_API = prefixes[i] + 'Hidden';
visibility_change_handler = prefixes[i] + 'visibilitychange';
}
}
}
if (!page_visibility_API)
{
//PageVisibility API is not supported in this device
return page_visibility_API;
}
return {"hidden": page_visibility_API, "handler": visibility_change_handler};
}
if (PV_API)
{
document.addEventListener(PV_API.handler, function(){
//console.log("current_window_id", current_window_id, "document[PV_API.hidden]", document[PV_API.hidden]);
if (document[PV_API.hidden])
{
//windows is hidden now
remove_from_active_windows(current_window_id);
//skip_once = true;
}
else
{
//windows is visible now
//add_to_active_windows(current_window_id);
//skip_once = false;
check_current_window_status ();
}
}, false);
}
/********************************************
** ADD CURRENT WINDOW TO main_windows LIST **
*********************************************/
add_to_main_windows_list(current_window_id);
//update active_window to current window
localStorage.active_window = current_window_id;
/**************************************************************************
** REMOVE CURRENT WINDOWS FROM THE main_windows LIST ON CLOSE OR REFRESH **
***************************************************************************/
window.addEventListener('beforeunload', function ()
{
remove_from_main_windows_list(current_window_id);
});
/*****************************
** ADD TO main_windows LIST **
******************************/
function add_to_main_windows_list(window_id)
{
var temp_main_windows_list = get_main_windows_list();
var index = temp_main_windows_list.indexOf(window_id);
if (index < 0)
{
//this windows is not in the list currently
temp_main_windows_list.push(window_id);
}
localStorage.main_windows = temp_main_windows_list.join(",");
return temp_main_windows_list;
}
/**************************
** GET main_windows LIST **
***************************/
function get_main_windows_list()
{
var temp_main_windows_list = [];
if (localStorage.main_windows)
{
temp_main_windows_list = (localStorage.main_windows).split(",");
}
return temp_main_windows_list;
}
/**********************************************
** REMOVE WINDOWS FROM THE main_windows LIST **
***********************************************/
function remove_from_main_windows_list(window_id)
{
var temp_main_windows_list = [];
if (localStorage.main_windows)
{
temp_main_windows_list = (localStorage.main_windows).split(",");
}
var index = temp_main_windows_list.indexOf(window_id);
if (index > -1) {
temp_main_windows_list.splice(index, 1);
}
localStorage.main_windows = temp_main_windows_list.join(",");
//remove from active windows too
remove_from_active_windows(window_id);
return temp_main_windows_list;
}
/**************************
** GET active_windows LIST **
***************************/
function get_active_windows_list()
{
var temp_active_windows_list = [];
if (localStorage.actived_windows)
{
temp_active_windows_list = (localStorage.actived_windows).split(",");
}
return temp_active_windows_list;
}
/*************************************
** REMOVE FROM actived_windows LIST **
**************************************/
function remove_from_active_windows(window_id)
{
var temp_active_windows_list = get_active_windows_list();
var index = temp_active_windows_list.indexOf(window_id);
if (index > -1) {
temp_active_windows_list.splice(index, 1);
}
localStorage.actived_windows = temp_active_windows_list.join(",");
return temp_active_windows_list;
}
/********************************
** ADD TO actived_windows LIST **
*********************************/
function add_to_active_windows(window_id)
{
var temp_active_windows_list = get_active_windows_list();
var index = temp_active_windows_list.indexOf(window_id);
if (index < 0)
{
//this windows is not in active list currently
temp_active_windows_list.push(window_id);
}
localStorage.actived_windows = temp_active_windows_list.join(",");
return temp_active_windows_list;
}
/*****************
** MANAGE CRASH **
******************/
//If the last update didn't happened recently (more than time_period*2)
//we will clear saved localStorage's data and reload the page
function manage_crash()
{
if (localStorage.last_update)
{
if (parseInt(localStorage.last_update) + (time_period * 2) < Date.now())
{
//seems a crash came! who knows!?
//localStorage.clear();
localStorage.removeItem('main_windows');
localStorage.removeItem('actived_windows');
localStorage.removeItem('active_window');
localStorage.removeItem('last_update');
location.reload();
}
}
}
/********************************
** CHECK CURRENT WINDOW STATUS **
*********************************/
function check_current_window_status(test)
{
manage_crash();
if (PV_API)
{
var active_status = "Inactive";
var windows_list = get_main_windows_list();
var active_windows_list = get_active_windows_list();
if (windows_list.indexOf(localStorage.active_window) < 0)
{
//last actived windows is not alive anymore!
//remove_from_main_windows_list(localStorage.active_window);
//set the last added window, as active_window
localStorage.active_window = windows_list[windows_list.length - 1];
}
if (! document[PV_API.hidden])
{
//Window's page is visible
localStorage.active_window = current_window_id;
}
if (localStorage.active_window == current_window_id)
{
active_status = "Active";
}
if (active_status == "Active")
{
active_windows_list = add_to_active_windows(current_window_id);
}
else
{
active_windows_list = remove_from_active_windows(current_window_id);
}
console.log(test, active_windows_list);
var element_holder = document.getElementById("holder_element");
element_holder.insertAdjacentHTML("afterbegin", "<div>"+element_holder.childElementCount+") Current Windows is "+ active_status +" "+active_windows_list.length+" window(s) is visible and active of "+ windows_list.length +" windows</div>");
}
else
{
console.log("PageVisibility API is not supported :(");
//our INACTIVE pages, will remain INACTIVE forever, you need to make some action in this case!
}
localStorage.last_update = Date.now();
}
//check storage continuously
setInterval(function(){
check_current_window_status ();
}, time_period);
//initial check
check_current_window_status ();
</script>
</body>
</html>
I'm sure this is a super easy fix and I just can't see it..
I have a play button and I only want it to write to database (inc playcount) only when it's clicked the first time.
Any idea why this doesn't work? This result counts every click, and if I do if countonce = 0 and declare at beginning as 0 it won't count any clicks. Am I misunderstanding javascript?
<div id="left-05-play_">
<script type="text/javascript">
var currsong = 1;
var playcountadd = document.getElementById('left-05-play_');
playcountadd.onclick = function() {
if (countonce != 1) {
$.post( "php/songadd.php", { addsong: "1", } );
var countonce = 1;
} }
</script>
</div>
Thank-you for taking the time to read this question.
This should do the trick.
var currsong = 1;
var songadded = false;
var playcountadd = document.getElementById('left-05-play_');
playcountadd.onclick = function() {
if (!songadded) {
$.post( "php/songadd.php", { addsong: "1", } );
songadded = true;
}
}
Changed countonce to songadded
Moved songadded out of onclick function
Changed songadded to boolean logic
Check whether songadded=false before proceeding with AJAX post
I have a javascript function on the child page that I need to run when the save button on the master page is clicked.
ValidateCheckList = function() {
var ErrorCodeU1001 = "U1001";
var ErrorCodeU1002 = "U1002";
var ErrorCodeU1003 = "U1003";
var errors = [];
$('<%= errorsHiddenField.ClientID %>').val("0");
var fingerprintsTaken = $('<%= FingerprintsTakenYesNo.PluginSelector %>').YesNoPlugin(YesNoMethodsEnum.IsYes);
if (!fingerprintsTaken) {
errors.push(ErrorCodeU1001);
}
var dnaTaken = $('<%= DNATakenYesNo.PluginSelector %>').YesNoPlugin(YesNoMethodsEnum.IsYes);
if (!dnaTaken) {
errors.push(ErrorCodeU1002);
}
var photographTaken = $('<%= PhotographTakenYesNo.PluginSelector %>').YesNoPlugin(YesNoMethodsEnum.IsYes);
if (!photographTaken) {
errors.push(ErrorCodeU1003);
}
if (errors.length > 0) {
('<%= errorsHiddenField.ClientID %>').val(errors.length.toString());
$(document).PageUtilPlugin(PageUtilMethodsEnum.DisplayUserNotificationMessage, { messageType: "Warning", message: errors });
}
}
I have tried -
$(document).ready(function() {
document.getElementById("ctl00_ctl00_ContentPlaceHolder1_SaveButton").onclick = ValidateCheckList;
but this doesn't work.
It also needs to do a postback.
Can anyone help?
thanks
try this
change you code like this
function ValidateCheckList ()
{
if(allvalidates)
return true;
else
return false;
}
on master page save button in page load
button.Attribute.Add("OnClick", "return ValidateCheckList ()");
what do you mean with the parent and child exactly ?
if you mean the pop-ed up window is the child window you can use this
childwindow = window.open("child.html", "Pop", "width=700,height=400, scrollbars=1");
childwindow.yourfunction();