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localStorage clears on refresh, parse & stringify not working

Working on a practice app with localStorage, but the stored data is getting cleared on page refresh. Based on answers to similar questions, I've used JSON.stringify(); on setItem, and JSON.parse(); on getItem, but still no luck. Am I using those methods in the wrong way? For reference, #petType and #petName are input IDs, and #name and #type are ul IDs. Thanks!
var animalArray = [];
var addPet = function(type,name) {
var type = $("#petType").val();
var name = $("#petName").val();
localStorage.setItem("petType", JSON.stringify(type));
localStorage.setItem("petName", JSON.stringify(name));
animalArray.push(type,name);
};
var logPets = function() {
animalArray.forEach( function(element,index) {
//empty array
animalArray.length = 0;
//empty input
$("input").val("");
var storedName = JSON.parse(localStorage.getItem("petName"));
var storedType = JSON.parse(localStorage.getItem("petType"));
//append localStorage values onto ul's
$("#name").append("<li>" + storedName + "</li>");
$("#type").append("<li>" + storedType + "</li>");
});
};
//click listPets button, call logPets function
$("#listPets").on("click", function() {
logPets();
$("#check").html("");
});
//click enter button, call addPet function
$("#enter").on("click", function() {
addPet(petType,petName);
$("#check").append("<i class='fa fa-check' aria-hidden='true'></i>");
});

It appears to clear because you are not loading data from it when the page loads. There are multiple bugs in the code:
It appears that you're only saving the last added pet to localStorage, which would create inconsistent behaviour
Setting animalArray.length to 0 is incorrect
animalArray.push(type, name); is probably not what you want, since it adds 2 items to the array, do something like animalArray.push({type: type, name: name});
logPets can just use the in memory array, since it's identical to the one saved
Fixed code:
var storedArray = localStorage.getItem("animalArray");
var animalArray = [];
if(storedArray) {
animalArray = JSON.parse(storedArray);
}
var addPet = function(type,name) {
var type = $("#petType").val();
var name = $("#petName").val();
animalArray.push({type: type, name: name});
localStorage.setItem("animalArray", JSON.stringify(animalArray));
};
var logPets = function() {
animalArray.forEach( function(element,index) {
//empty input
$("input").val("");
//append localStorage values onto ul's
$("#name").append("<li>" + element.name + "</li>");
$("#type").append("<li>" + element.type + "</li>");
});
};
//click listPets button, call logPets function
$("#listPets").on("click", function() {
logPets();
$("#check").html("");
});
//click enter button, call addPet function
$("#enter").on("click", function() {
addPet(petType,petName);
$("#check").append("<i class='fa fa-check' aria-hidden='true'></i>");
});
A quick fiddle to demo it: https://jsfiddle.net/rhnnvvL0/1/

JavaScript local storage for pages

I have here a little script that I found and am using it to create a simple game of sorts...
/*
Here add:
'image_path': ['id_elm1', 'id_elm2']
"id_elm1" is the ID of the tag where the image is initially displayed
"id_elm2" is the ID of the second tag, where the image is moved, when click on the first tag
*/
var obimids = {
'http://www.notreble.com/buzz/wp-content/uploads/2011/12/les-claypool-200x200.jpg': ['lesto', 'les'],
'http://rs902.pbsrc.com/albums/ac223/walkingdeadheartbreaker/Muzak/Guitarists/LarryLalondePrimus.jpg~c200': ['lerto', 'ler'],
'http://www.noise11.com/wp/wp-content/uploads/2014/07/Primus-Alexander-200x200.jpg': ['timto', 'tim']
};
// function executed when click to move the image into the other tag
function whenAddImg() {
/* Here you can add a code to be executed when the images is added in the other tag */
return true;
}
/* From here no need to edit */
// create object that will contain functions to alternate image from a tag to another
var obaImg = new Object();
// http://coursesweb.net/javascript/
// put the image in element with ID from "ide"
obaImg.putImg = function(img, ide, stl) {
if(document.getElementById(ide)) {
document.getElementById(ide).innerHTML = '<img src="'+ img+ '" '+stl+' />';
}
}
// empty the element with ID from "elmid", add image in the other element associated to "img"
obaImg.alternateImg = function(elmid) {
var img = obaImg.storeim[elmid];
var addimg = (elmid == obimids[img][0]) ? obimids[img][1] : obimids[img][0];
$('#'+elmid+ ' img').hide(800, function(){
$('#'+elmid).html('');
obaImg.putImg(img, addimg, 'style="display:none;"');
$('#'+addimg+ ' img').fadeIn(500);
});
// function executed after the image is moved into "addimg"
whenAddImg();
}
obaImg.storeim = {}; // store /associate id_elm: image
// add 'image': 'id_elm1', and 'image': 'id_elm1' in "storeim"
// add the image in the first tag associated to image
// register 'onclick' to each element associated with images in "obimids"
obaImg.regOnclick = function() {
for(var im in obimids) {
obaImg.storeim[obimids[im][0]] = im;
obaImg.storeim[obimids[im][2]] = im;
obaImg.putImg(im, obimids[im][0], '');
document.getElementById(obimids[im][0]).onclick = function(){ obaImg.alternateImg(this.id); };
document.getElementById(obimids[im][3]).onclick = function(){ obaImg.alternateImg(this.id); };
}
}
obaImg.regOnclick(); // to execute regOnclick()
FIDDLE
When clicking the items it adds them to a container where I'd like them to be stored if the user navigates to another page. I have seen some local storage cookie code on another script
FIDDLE
var $chks = $('.compare').change(function () {
console.log('c', this)
if ($(this).is(':checked')) {
var img = $('<img>'),
findimg = $(this).closest('.box').find('img'),
data_term = findimg.data('term');
img.attr('src', findimg.attr('src'));
img.attr('data-term', data_term);
var input = '<input type="hidden" name="imagecompare" value="' + data_term + '">';
$('#area').find('div:empty:first').append(img).append(input);
} else {
var term = $(this).data('term'),
findboximage = $('#area > div > img[data-term=' + term + ']')
findboximage.parent('div').empty();
}
localStorage.setItem("imagecookie", $chks.filter(':checked').map(function () {
return $(this).data('term')
}).get().join(','));
});
$(document).on('click', '#area > div', function () {
$(this).empty();
localStorage.clear();
});
var cookie = localStorage.getItem("imagecookie");
if (cookie) {
var terms = cookie.split(',');
if (terms.length) {
$chks.filter($.map(terms, function (val) {
return '[data-term="' + val + '"]'
}).join()).prop('checked', true).change();
}
}
but can't figure how to apply something similar to this one. I would be grateful for any help or to be pointed to some useful places for help.

How to remove null from my Javascript

So, here's my script:
$(function () {
// define this here because we're changing the ID
var $twitter = $('twitter');
// bind to select inside iframe
$('#iframe').on('load', function () {
$(this).contents().find('#cds').change(function () {
var selectVal = $(this).val();
url = 'https://twitter.com/intent/tweet?button_hashtag=stream&text=Just enjoying ' + selectVal + ' on';
$twitter.attr("id", url);
}).change(); // trigger change to get initial value
});
});
Basically, it takes the selected value from my select box, and outputs it into a twitter link. The problem is, when nothing is selected, it outputs "null", and I was wondering if there was a way to detect this, and echo something else.

Try this:
var selectVal = $(this).val() || 'default value';

Toggling two events on one button

I'm trying to add some functionality to be able to edit comments inline. So far it's pretty close, but I'm experiencing issues trying to trigger a second event. It works the first time, but after that, fails.
$(function() {
var $editBtn = $('.js-edit-comment-btn');
var clicked = false;
$editBtn.on('click', $editBtn, function() {
clicked = true;
var $that = $(this);
var $form = $that.closest('.js-edit-comment');
var $commentTextBody = $that.closest('div').find('.js-comment-body');
var commentText = $commentTextBody.text();
var $editableText = $('<textarea />');
if ($that.text() === 'Save Edits') {
$that.text('Saving...').attr('disabled', true);
} else {
$that.text('Save Edits').attr('alt', 'Save your edits');
}
// Replace div with textarea, and populate it with the comment text
var makeDivTextarea = function($editableText, commentText, $commentTextBody) {
$editableText.val(commentText);
$commentTextBody.replaceWith($editableText);
$editableText.addClass('gray_textarea js-edited-comment').width('100%').css('padding', '4px').focus();
};
makeDivTextarea($editableText, commentText, $commentTextBody);
var saveEdits = function($that, $editableText) {
$that.on('click', $that, function() {
if (clicked) {
var comment = $that.closest('div').find('.js-edited-comment').val();
$editableText.wrap('<div class="js-comment-body" />').replaceWith(comment);
$that.text('Edit').attr('alt', 'Edit Your Comment').attr('disabled', false);
$('#output').append('saved');
clicked = false;
return false;
}
});
};
saveEdits($that, $editableText);
return false;
});
});​
jsfiddle demo here

Hiya demo for your working solution: http://jsfiddle.net/8P6uz/
clicked=true was the issue :)) I have rectified another small thing. i.e. $('#output') is set to empty before appending another saved hence text **saved** will only appear once.
small note: If I may suggest use Id of the button or if there are many edit buttons try using this which you already i reckon; I will see if I can write this more cleaner but that will be sometime latter-ish but this should fix your issue. :) enjoy!
Jquery Code
$(function() {
var $editBtn = $('.js-edit-comment-btn');
var clicked = false;
$editBtn.on('click', $editBtn, function() {
clicked = true;
var $that = $(this);
var $form = $that.closest('.js-edit-comment');
var $commentTextBody = $that.closest('div').find('.js-comment-body');
var commentText = $commentTextBody.text();
var $editableText = $('<textarea />');
if ($that.text() === 'Save Edits') {
$that.text('Saving...').attr('disabled', true);
} else {
$that.text('Save Edits').attr('alt', 'Save your edits');
}
// Replace div with textarea, and populate it with the comment text
var makeDivTextarea = function($editableText, commentText, $commentTextBody) {
$editableText.val(commentText);
$commentTextBody.replaceWith($editableText);
$editableText.addClass('gray_textarea js-edited-comment').width('100%').css('padding', '4px').focus();
};
makeDivTextarea($editableText, commentText, $commentTextBody);
var saveEdits = function($that, $editableText) {
$that.on('click', $that, function() {
if (clicked) {
var comment = $that.closest('div').find('.js-edited-comment').val();
$editableText.wrap('<div class="js-comment-body" />').replaceWith(comment);
$that.text('Edit').attr('alt', 'Edit Your Comment').attr('disabled', false);
$('#output').text("");
$('#output').append('saved');
clicked = true;
return false;
}
});
};
saveEdits($that, $editableText);
return false;
});
});​

How to get jQuery placeholder/watermark plugin to work for ajax loaded text fields?

I'm using the following placeholder plugin
(function($){
var ph = "PLACEHOLDER-INPUT";
var phl = "PLACEHOLDER-LABEL";
var boundEvents = false;
var default_options = {
labelClass: 'placeholder'
};
//check for native support for placeholder attribute, if so stub methods and return
var input = document.createElement("input");
if ('placeholder' in input) {
$.fn.placeholder = $.fn.unplaceholder = function(){}; //empty function
delete input; //cleanup IE memory
return;
};
delete input;
//bind to resize to fix placeholders when the page resizes (fields are hidden/displayed, which can change positioning).
$(window).resize(checkResize);
$.fn.placeholder = function(options) {
bindEvents();
var opts = $.extend(default_options, options)
this.each(function(){
var rnd=Math.random().toString(32).replace(/\./,'')
,input=$(this)
,label=$('<label style="position:absolute;display:none;top:0;left:0;"></label>');
if (!input.attr('placeholder') || input.data(ph) === ph) return; //already watermarked
//make sure the input tag has an ID assigned, if not, assign one.
if (!input.attr('id')) input.attr('id', 'input_' + rnd);
label .attr('id',input.attr('id') + "_placeholder")
.data(ph, '#' + input.attr('id')) //reference to the input tag
.attr('for',input.attr('id'))
.addClass(opts.labelClass)
.addClass(opts.labelClass + '-for-' + this.tagName.toLowerCase()) //ex: watermark-for-textarea
.addClass(phl)
.text(input.attr('placeholder'));
input
.data(phl, '#' + label.attr('id')) //set a reference to the label
.data(ph,ph) //set that the field is watermarked
.addClass(ph) //add the watermark class
.after(label) //add the label field to the page
//setup overlay
itemFocus.call(this);
itemBlur.call(this);
});
};
$.fn.unplaceholder = function(){
this.each(function(){
var input=$(this),
label=$(input.data(phl));
if (input.data(ph) !== ph) return;
label.remove();
input.removeData(ph).removeData(phl).removeClass(ph).unbind('change',itemChange);
});
};
function bindEvents() {
if (boundEvents) return;
//prepare live bindings if not already done.
$("form").live('reset', function(){
$(this).find('.' + ph).each(itemBlur);
});
$('.' + ph)
.live('keydown',itemFocus)
.live('mousedown',itemFocus)
.live('mouseup',itemFocus)
.live('mouseclick',itemFocus)
.live('focus',itemFocus)
.live('focusin',itemFocus)
.live('blur',itemBlur)
.live('focusout',itemBlur)
.live('change',itemChange);
;
$('.' + phl)
.live('click', function() { $($(this).data(ph)).focus(); })
.live('mouseup', function() { $($(this).data(ph)).focus(); });
bound = true;
boundEvents = true;
};
function itemChange() {
var input = $(this);
if (!!input.val()) {
$(input.data(phl)).hide();
return;
}
if (input.data(ph+'FOCUSED') != 1) {
showPHL(input);
}
}
function itemFocus() {
$($(this).data(ph+'FOCUSED',1).data(phl)).hide();
};
function itemBlur() {
var that = this;
showPHL($(this).removeData(ph+'FOCUSED'));
//use timeout to let other validators/formatters directly bound to blur/focusout work
setTimeout(function(){
var input = $(that);
//if the item wasn't refocused, test the item
if (input.data(ph+'FOCUSED') != 1) {
showPHL(input);
}
}, 200);
};
function showPHL(input, forced) {
var label = $(input.data(phl));
//if not already shown, and needs to be, show it.
if ((forced || label.css('display') == 'none') && !input.val())
label
.text(input.attr('placeholder'))
.css('top', input.position().top + 'px')
.css('left', input.position().left + 'px')
.css('display', 'block');
//console.dir({ 'input': { 'id':input.attr('id'), 'pos': input.position() }});
}
var cr;
function checkResize() {
if (cr) window.clearTimeout(cr);
cr = window.setTimeout(checkResize2, 50);
}
function checkResize2() {
$('.' + ph).each(function(){
var input = $(this);
var focused = $(this).data(ph+'FOCUSED');
if (!focused) showPHL(input, true);
});
}
}(jQuery));
It applies the placeholder attribute to form fields in browsers that do not natively support the placeholder attribute (ex. IE9). It works for statically loaded text fields, however for text fields that are loaded via ajax, the placeholder does not appear.
Is it possible to achieve this 'watermark' effect on text fields that are loaded via ajax?

What happens if you trigger the window resize function after adding in new inputs?
$(window).trigger('resize')

You could apply the plugin to newly created controls after the AJAX call completes. Forgive the pseudo-code as I'm not really sure about how your AJAX calls are working:
$.ajax({
url: "test.html",
cache: false
}).done(function( result ) {
field = $('<input>').html(result);
$("#results").append(field);
field.placeholder();
});
Another option is that you could use jQuery's .on() method to bind dynamically created controls to the function--but it wants an event (like click). I'm not sure how you would do that. Maybe something like this:
$( 'body' ).on('click','input.addField', function(e){
$(this).placeholder();
});
I know this won't work, but maybe it helps get you brainstorm solutions.