Develop Reference

Javascript - Use array values dynamically in HTML

My end result is supposed to be a list of objects in html. Bootstrap behind this. I'd like for the list to be created dynamically so I don't have to manually create all the divs because I don't know how many there will be. Here's what I have.
I have an array similar to this:
activities =
[
{
"activityOwner": "Raymond Carlson",
"activityDesc": "Complete all the steps from Getting Started wizard"
},
{
"activityOwner": "Flopsy McDoogal",
"activityDesc": "Called interested in March fundraising Sponsorship"
},
{
"activityOwner": "Gary Busy",
"activityDesc": "Get approval for price quote"
}
]
This is the first part where I'm not sure what to do. I can assign the element ids individually for my html like this but what I'd like to do is count how many elements are in my array and create these for me. I won't know how many there are to make these manually. I'm sure there needs to be a loop but I couldn't figure it out.
document.getElementById('activityowner0').innerHTML = activities[0].activityOwner;
document.getElementById('activitydesc0').innerHTML = activities[0].activityDesc;
document.getElementById('activityowner1').innerHTML = activities[1].activityOwner;
document.getElementById('activitydesc1').innerHTML = activities[1].activityDesc;
document.getElementById('activityowner2').innerHTML = activities[2].activityOwner;
document.getElementById('activitydesc2').innerHTML = activities[2].activityDesc;
etc.
etc.
And then...once I have that part, I'd like to know how to create my html divs dynamically based on how many elements are in my array. Again, right now I don't know how many there are so I'm having to create a bunch of these and then have extras if I have too many.
<div class="container">
<div class="row"></div>
<div class="qa-message-list" id="wallmessages">
<br>
<div class="message-item" id="m0">
<div class="message-inner">
<div class="message-head clearfix">
<div class="user-detail">
<h5 class="handle">
<p id='activityowner0'></p>
</h5>
<div class="post-meta"></div>
</div>
</div>
<div class="qa-message-content">
<p id='activitydesc0'></p>
</div>
</div>
</div>
I know this is a big ask so just pointing me in the right direction would be very helpful. I hope my question was clear and I appreciate it.

One way for you to achieve this would be to loop through the objects in your activities array. From there you can use a HTML template to store the base HTML structure which you can clone and update with the values of each object before you append it to the DOM.
In addition, an important thing to note when generating repeated content in a loop: never use id attributes. You will either end up with duplicates, which is invalid as id need to be unique, or you'll end up with ugly code generating incremental/random id at runtime which is unnecessary. Use classes instead.
Here's a working example:
const activities = [{ "activityOwner": "Raymond Carlson", "activityDesc": "Complete all the steps from Getting Started wizard"}, {"activityOwner": "Flopsy McDoogal","activityDesc": "Called interested in March fundraising Sponsorship" }, { "activityOwner": "Gary Busy", "activityDesc": "Get approval for price quote" }]
const html = activities.map(obj => {
let item = document.querySelector('#template').innerHTML;
item = item.replace('{owner}', obj.activityOwner);
item = item.replace('{desc}', obj.activityDesc);
return item;
});
document.querySelector('#list').innerHTML = html.join('');
<div id="list"></div>
<template id="template">
<div class="container">
<div class="row"></div>
<div class="qa-message-list">
<div class="message-item">
<div class="message-inner">
<div class="message-head clearfix">
<div class="user-detail">
<h5 class="handle">
<p class="activityowner">{owner}</p>
</h5>
<div class="post-meta"></div>
</div>
</div>
<div class="qa-message-content">
<p class="activitydesc">{desc}</p>
</div>
</div>
</div>
</div>
</div>
</template>

Conditionally hide the nth element of a v-for loop without modifying the array. vue 3 composition api search function

I have a ref variable (foxArticles ), which holds a list that contains 100 items. In a v-for loop i loop over each value. As a result, i have 100 values rendered on the page.
<template>
<div class="news_container">
<div
v-for="article in foxArticles"
v-bind:key="article"
class="article_single_cell"
>
<div
class="news_box shadow hover:bg-red-100 "
v-if="containsKeyword(article, keywordInput)"
>
<div class="news_box_right">
<div class="news_headline text-red-500">
<a :href="article.url" target="_blank">
{{ article.title }}
</a>
</div>
</div>
</div>
</div>
</div>
</template>
<script>
const foxArticles = ref([]);
</script>
I also have a search function, which returns the value, if it includes the passed in keyword. The function is used in the child of the v-for loop.
<div class="search_input_container">
<input
type="text"
class="search_input"
v-model="keywordInput"
/>
</div>
<script>
const keywordInput = ref("");
function containsKeyword(article, keywordInput) {
if (article.title.toLowerCase().includes(keywordInput.toLowerCase())) {
return article;
}
}
</script>
The problem is, i can't use .slice() on the foxArticles array in the v-for loop, because that screws up the search functionality, as it returns only the values from the sliced range.
How can i have the access the all of the values of the array, while not rendering all 100 of returned articles on the initial load?
Any suggestions?

I think your approach will make it incredibly complex to achieve. It would be simpler to always iterate over some set, this set is either filtered based on a search-term, or it will be the first 100 items.
I'm not very familiar yet with the Vue 3 composition api so I'll demonstrate with a regular (vue 2) component.
<template>
<div class="news_container">
<div
v-for="article in matchingArticles"
v-bind:key="article"
class="article_single_cell"
>
... news_box ...
</div>
</div>
</template>
<script>
export default {
...
computed: {
matchingArticles() {
var articles = this.foxArticles;
if (this.keywordInput) {
articles = articles.filter(article => {
return this.containsKeyword(article, this.keywordInput)
})
} else {
// we will limit the result to 100
articles = articles.slice(0, 100);
}
// you may want to always limit results to 100
// but i'll leave that up to you.
return articles;
}
},
....
}
</script>
Another benefit is that the template does not need to worry about filtering results.

ok, so i kind of came up with another solution, for which you don't have to change the script part...
instead of having one v-for loop , you can make two of them, where each one is wrapped in a v-if statement div
The first v-if statement says, If the client has not used the search (keywordInput == ''), display articles in the range of (index, index)
The second one says = If the user has written something (keywordInput != ''), return those articles.
<template>
<div class="news_container">
<!-- if no search has been done -->
<div v-if="keywordInput == ''">
<div
v-for="article in foxArticles.slice(0, 4)"
v-bind:key="article"
class="article_single_cell"
>
<div class="news_box shadow hover:bg-red-100 ">
<div class="news_box_right">
<div class="news_headline text-red-500">
<a :href="article.url" target="_blank">
{{ article.title }}
</a>
</div>
</div>
</div>
</div>
</div>
<!-- if searched something -->
<div v-else-if="keywordInput != ''">
<div
v-for="article in foxArticles"
v-bind:key="article"
class="article_single_cell"
>
<div
class="news_box shadow hover:bg-red-100 "
v-if="containsKeyword(article, keywordInput) && keywordInput != ''"
>
<div class="news_box_right">
<div class="news_headline text-red-500">
<a :href="article.url" target="_blank">
{{ article.title }}
</a>
</div>
</div>
</div>
</div>
</div>
</div>
</template>
im not sure how this impacts performance tho, but that's a problem for another day

JSON to unordered list, sorted

I have an xml file that I made a JSON array with objects that are senators with a party, name, and a status of whether they have been voted or not. Only the name needs to be displayed on my HTML list. I don't know how to get it there, though, and I want to sort democrats and republicans dynamically as I go. here is a sample of the array:
[{"name":"Chuck Schumer","party":"Democrat","voted":false},
{"name":"Dick Durbin","party":"Democrat","voted":false}, ...]
I'm not sure how one does this. I have ID elements set up in my html because I know I need that.
Do I need to JSON.parse first? how do you connect them to the ID values?
Here is my HTML body.
<div id="dropLists" style="display: table">
<div style="display: table-row">
<div class="dropList">
<fieldset>
<legend>Democrats:</legend>
<ul id="democrats">
</ul>
</fieldset>
</div>
<div class="dropList">
<fieldset>
<legend>Republicans:</legend>
<ul id="republicans">
</ul>
</fieldset>
</div>
</div>
</div>

You're almost there. Here's an overview:
document.querySelector to select the 2 ul elements
document.createElement to create li elements
element.appendChild to insert the li elements into the `uls element.
let data = [{
"name": "Chuck Schumer",
"party": "Democrat",
"voted": false
},
{
"name": "Dick Durbin",
"party": "Democrat",
"voted": false
},
{
"name": "X Y Z",
"party": "Republican",
"voted": false
},
];
data.forEach(({name, party}) => {
let itemEl = document.createElement('li');
itemEl.textContent = name;
let listId = party === 'Democrat' ? '#democrats' : '#republicans';
let listEl = document.querySelector(listId);
listEl.appendChild(itemEl);
});
<div id="dropLists" style="display: table">
<div style="display: table-row">
<div class="dropList">
<fieldset>
<legend>Democrats:</legend>
<ul id="democrats">
</ul>
</fieldset>
</div>
<div class="dropList">
<fieldset>
<legend>Republicans:</legend>
<ul id="republicans">
</ul>
</fieldset>
</div>
</div>
</div>

Filter the list to get either "democrats" or "republicans", map the results to have only the name wrapped in a li and set the innerHTML of the coresponding ul ( html elements with id will be global variables, so you do democrats.innerHTML = ... )
const data = [{"name":"Chuck Schumer","party":"Democrat","voted":false},{"name":"Dick Durbin","party":"Democrat","voted":false},{"name":"Dick Durbin 2","party":"Republican","voted":false}]
democrats.innerHTML = data.filter(o => o.party === "Democrat").map(o => '<li>' + o.name + '</li>').join('');
republicans.innerHTML = data.filter(o => o.party === "Republican").map(o => '<li>' + o.name + '</li>').join('');
<div id="dropLists" style="display: table">
<div style="display: table-row">
<div class="dropList">
<fieldset>
<legend>Democrats:</legend>
<ul id="democrats">
</ul>
</fieldset>
</div>
<div class="dropList">
<fieldset>
<legend>Republicans:</legend>
<ul id="republicans">
</ul>
</fieldset>
</div>
</div>
</div>

Where is the code getting the data from? Is it reading an XML file? Calling a URL and downloading it? Or are you copying/pasting your array into the code? If you're copying/pasting it, then it's already an array and doesn't need to be JSON.parsed. If it's coming as the entire contents of a file obtained via fetch, then you can just use response.json() on the result of the fetch to convert it into an array. Any other source would likely give it to you as a string, in which case you just need to call JSON.parse() on the string to get the array.
Once you have an array, it's extremely easy to split it into two lists, one for each party:
const dems = senators.filter(senator => senator.party === 'Democrat');
const reps = senators.filter(senator => senator.party === 'Republican');
And then to convert them to an HTML list inside your existing ul elements:
const demList = document.getElementById('democrats');
dems.forEach(dem => {
const listItem = document.createElement('li');
listItem.textContent = dem.name;
demList.appendChild(listItem);
});
(The code is similar for the Republican list.)

adding items with ngFor with multiple arrays

Im trying to list some data from 2 different arrays - I need to keep the arrays seperate so i can differenciate between the data. I also need to add a class on items from the first array.
I've tried:
<div class="divInput" id="divC">
<div class="divTextInput">
<input /><button>Add</button>
</div>
<div id="CWrapper" class="tableWrapper">
<div class="cell" *ngFor="let c1 of data.c1">
<p title={{c1}}>{{c1}}</p><span></span>
</div>
<div class="cell kle" *ngFor="let c2 of data.c2">
<img src={{imagePath}}>
<p title={{c2}}>{{c2}}</p><span></span>
</div>
</div>
</div>
The kle class doesnt add any css, it's just there so i can differentiate between the two, and do trigger events.
Where the data class is:
class Data {
c1: string[];
c2: string[];
}
Adding to the array with:
$('#divC .divTextInput button').on('click', (ev) => {
let button = $(ev.currentTarget);
let input = button.prev();
if (input.val()) {
this.data.c1.push(<string>input.val());
this.data.c2.push(<string>input.val());
}
});
When i add a string to c2, it adds it to the html, but when i add a string to c1 it doesnt add to the html (Only div with class="cell kle" is added)
It adds the data that initially is in the array, but not when i add dynamically
If i log the arrays, they both have the added string.
-- Update --
It works if the arrays arent in a class.

Vue.js change model attached to a form upon clicking a list

I have an array of objects. These objects are loaded into a list in vue.js.
Aside from this list, I have a form that displays data from one of these objects. I want to, when clicking one of the list's elements, it will bind this specific object to the form and show its data.
How can do this in Vue.js?
My list code is:
<div id="app-7">
<ul id="food-list" v-cloak>
<food-item v-for="item in foodList" v-bind:food="item" v-bind:key="item.id" inline-template>
<li class="food">
<div class="food-header">
<img :src="'img/' + food.slug +'.png'">
<div class="food-title">
<p>{{food.name}} |
<b>{{food.slug}}</b>
</p>
<p>quantity: {{food.quantity}}</p>
</div>
<div class="food-load"> // load into form upon clicking this
</div>
</div>
</li>
</food-item>
</ul>
</div>

Since I do not have the code for the form, this is my best guess without clarification.
You can add a click handler to the item you want to be clicked. It will pass the value of the food item into the method.
<div class="food-load" #click="setFoodItem(item)">
</div>
And when that method is called, it can assign the clicked item to a data property. I'm not sure where your form is, and if it is in a different component. If it is in a child component, you would have to pass it in as a prop, or emit an event to pass it to a parent component.
data() {
return {
//create a reactive field to store the current object for the form.
foodItemForm: null
};
},
methods: {
//method for setting the current item for the form.
setFoodItem(item) {
this.foodItemForm = item;
}
}

Missing quite a bit of info in your sample code, your script is very important to see to make sense of what you would like to accomplish and where things might be going wrong.
Here's a quick list of the issue I came across with your code:
v-for refers to an individual food item as 'item', inside the loop you're trying to access properties as 'food'
You don't wrap your code in a component unless you're importing the component
When binding a value to 'v-bind:src' (or shorthand ':src') only pass the url, you should be specifying this in your script not inline.
You're better off using a button and the 'v-on:click' (or shorthand '#click') to load your selected food item into your form
You should also include your Javascript
Regardless, here's how I would handle this (took the liberty in filling in some blanks):
<template>
<div id="app">
<ul id="food-list">
<!--<food-item v-for="item in foodList" v-bind:food="item" v-bind:key="item.id" inline-template>-->
<li v-for="item in foodList" class="food">
<div class="food-header">
<img :src="item.slug" v-bind:alt="item.slug" width="250px" height="auto">
<div class="food-title">
<p>{{item.name}} | <b>{{item.slug}}</b></p>
<p>quantity: {{item.quantity}}</p>
</div>
<button class="food-load" #click="loadFoodItem(item.id)">Load Food Item</button>
</div>
</li>
<!--</food-item>-->
</ul>
<form v-if="activeFoodId != null" id="foodItemForm" action="#">
<h3>Food Form</h3>
<label for="food-id">Id:</label>
<input id="food-id" type="number" v-bind:value="foodList[activeFoodId].id"><br/>
<label for="food-slug">Slug:</label>
<input id="food-slug" type="text" v-bind:value="foodList[activeFoodId].slug"><br/>
<label for="food-name">Name:</label>
<input id="food-name" type="text" v-bind:value="foodList[activeFoodId].name"><br/>
<label for="food-quantity">Quantity:</label>
<input id="food-quantity" type="number" v-bind:value="foodList[activeFoodId].quantity">
</form>
</div>
</template>
<script>
export default {
name: 'app',
data: function () {
return {
activeFoodId: null,
foodList: [
{
id: 1,
slug: 'http://3.bp.blogspot.com/-QiJCtE3yeOA/TWHfElpIbkI/AAAAAAAAADE/Xv6osICLe6E/s320/tomato.jpeg',
name: 'tomatoes',
quantity: 4
}, {
id: 2,
slug: 'https://img.purch.com/rc/300x200/aHR0cDovL3d3dy5saXZlc2NpZW5jZS5jb20vaW1hZ2VzL2kvMDAwLzA2NS8xNDkvb3JpZ2luYWwvYmFuYW5hcy5qcGc=',
name: 'bananas',
quantity: 12
}, {
id: 3,
slug: 'https://media.gettyimages.com/photos/red-apples-picture-id186823339?b=1&k=6&m=186823339&s=612x612&w=0&h=HwKqE1MrsWrofYe7FvaevMnSB89FKbMjT-G1E_1HpEw=',
name: 'apples',
quantity: 7
}
]
}
},
methods: {
loadFoodItem: function (foodItemId) {
console.log(foodItemId)
this.activeFoodId = foodItemId
}
}
}
</script>
<style>
/# Irrelevant #/
</style>
Hope it helps!