How to go through a JSON with buttons in ReactJS - reactjs

I want to move through the contents of a JSON file with buttons.
This is the basic structure of my JSON:
[
{
"page": "1",
"required": "true",
"question": "lorem ipsum",
},
{
"page": "2",
"required": "true",
"question": "lorem ipsum dolor",
}
]
I'm building a multi-step form and I want to get the questions from this JSON. Is there any way for me to have a Next button, that moves one index forward in the JSON file, and displays the info in that index? The page identifier is unique to every object.
I'm new to React, so any explanations will be appreciated!

In my opinion, in order to iterate through the questions of your JSON, you'll first need to parse it by using JSON.parse() (documentation).
So per exemple, let's say your component looks like this :
function Form() {
[questions, setQuestions] = JSON.parse(your_json);
[currentQuestion, setCurrentQuestion] = 0;
function nextQuestion {
setCurrentQuestion = currentQuestion + 1;
}
return (
<div>
<label>{{ questions[currentQuestion].question }}</label>
<input type="text" />
<button onclick={ nextQuestion }>Next Question</button>
</div>
);
}
By doing this, you'll parse the JSON text, changing it to an object format, and make you being able to call any value. Then we have a counter and we will be able to change it's value by calling setCurrentQuestion. The method nextQuestion() does exactly this.
Then, in our JSX, we can display the question based on it's position in the JSON, and go to the next question by clicking the button. React will react to the value change by itself and then, change the question value automatically.
I hope that my answer help while being clear enough and I didn't do any mistake typing it ^^

Related

Making reusable component for array data in reactjs

I want to make a footer component in react with a heading and several links under it like in the image.
Also I want to pass only an array for the links like the following.
const FooterLinksData = [
{
link1: "Insolvers",
link2: "How it works?",
link3: "I'm looking for job",
link4: "I'm looking to hire",
},
{
link1: "Features",
link2: "Pricing",
link3: "Schedule a Demo",
},
];
My code:
return (
<>
<li>
<a href="/" className="footer_link">
{props.data[`link${props.num + 1}`]}
</a>
</li>
// I have written this li tag for times in my code
// props.data is the array I passed using the parent
// props.num is the number (0 in this case) to get link1 from
// the object
</>
);
My problem is that first obj under the array has 4 items while the second one only have 3. Is there any way to make a reusable component for it?
You can add the title inside the json and use it to bracke. Something like
const FooterLinksData = [
{
"title":"some title",
"links":[
"Insolvers",
"How it works"
]
},
{
"title":"some other title",
"links":[
"other Insolvers",
"other How it works"
}]
];
so then you will do something like:
FooterLinksData.map(({title, links}) => ({
<div>
<div>{title}</div>
<ul>{links.map(link => <li>{link}</li>)}</ul>
</div>
})
})
If you ask this question, I assume you use FooterLinksData[x].link1, FooterLinksData[x].link2, FooterLinksData[x].link3 ..... to display your links.
You could change your code to use the map() function instead, not having to deal with a fixed number of links.
Can't really help with code since you didn't posted how you render your links.

Angular // ng-select Use interpolation within a textarea on a text pulled from an array

Still in my very first days with Angular and ran into a problem i can't get my head around.
What I am trying to accomplish is sort of creating a way to have a persons name added to a message template.
The templates are loaded from a file like this
this.http.get('../../assets/templatefiles/customtemplates.json').subscribe(data => {this.templateArray = data as any [];
The structure of the JSON file is as follows
[{
"Id": 1,
"Type": "SR Templates",
"Name": "Message 1",
"Body": "Some meaningful text here"
},
{
"Id": 2,
"Type": "SR Templates",
"Name": "Message 2",
"Body": "Some more meaningful text here"
},
{
"Id": 3,
"Type": "GTFO Templates",
"Name": "Message 3",
"Body": "Guess what? Exactly, some even more..blahhh"
}]
All good so far. Then, in my template I use ng-select to create the dropdown list to display the options grouped by Type
<ng-select [items]="templateArray"
bindLabel="Name"
bindValue="Body"
groupBy="Type"
[(ngModel)]="selectedTemplate"
>
<ng-template ng-optgroup-tmp let-item="item">
<strong>{{item.Id}}</strong>
</ng-template>
</ng-select>
So far...working it seems. Templates are grouped by Type and show up in the drop down just fine.
Below the selection is a textarea in which the "Body" value is supposed to be displayed. Works fine as well, when selecting a template from the drop down the text shows fine in the textarea.
The problem I am facing is that there is an input field for the persons name the message will be send to.
I get the name as follows:
<input type="text" [(ngModel)]="srcName" class="form-control" placeholder="Name">
The bit confusing me is how to get/add the persons name to the message using interpolation?
I was hoping for something like just having to change the text in the JSON and adding the interpolation to it but apparently that does not work hehe.
{
"Id": 1,
"Type": "SR Templates",
"Name": "Message 1",
"Body": "Dear {{srcName}, Some meaningful text here"
}
I've been searching up and down, but am ultimately stuck and am desperate for a nudge in the direction I would have to go to actually get that name inserted in the textarea together with the template from the array...
You can make a function that concatenates your selected template and the name in you input, like so:
onSubmit() {
this.message = `Dear ${this.srcName}, ${this.selectedTemplate}`;
}
And then you can add a button that executes this function:
<button (click)="onSubmit()">Submit</button>
Now whenever you select the template you want and add the name you want to the input and click on submit button, you will get a concatenated message with the info you want.
Here is a live demo if you want more explanation.
In the live demo a used a normal HTML select, but it should work the same with angular material select.
##EDIT
If you need to put your srcName inside of your templates body, you will have to create a place holder in your template's body, something like:
"Guess what? Exactly {srcName}, some even more..blahhh"
instead of:
"Guess what? Exactly, some even more..blahhh"
Then you will have to change the onSubmit function:
onSubmit() {
this.message = this.selectedTemplate.replace('{srcName}', this.srcName)
}
I also added the changes to to the live demo.

Access individual JSON array item and use for blog post dynamically

I'm building a simple Nuxt JS blog with a blog.json file containing an array of blog posts which contains:
Title (String)
Body (HTML markup)
Creation (Date)
I will attach the format of this shortly. I know how to iterate over each array item and display it on the page, and I also have a basic understanding and some basic experience with dynamic routing in Nuxt JS.
The problem I'm currently facing is I need to be able to access individual array items and use them as blog posts, e.g: pages/blog/_slug where _slug would be the title of a blog post, with hyphens + all lowercase automatically.
I'm wondering how I would access for instance the Winter blog post in my example and be able to go to mysite.com/blog/winter-blog-post using the following JSON format:
{
"blogs": [
{
"title": "Summer blog post",
"body": "<div class=\"post\">My blog content</div>",
"created": "2019-03-14 10:08:00"
}
{
"title": "Winter blog post",
"body": "<div class=\"post\">My blog content</div>",
"created": "2019-03-15 10:08:00"
},
{
"title": "Spring blog post",
"body": "<div class=\"post\">My blog content</div>",
"created": "2019-03-16 10:08:00"
}
]
}
I essentially want to be able to go to mysite.com/blog/winter-blog-post and have it use the content from that particular array item.
I'll assume you have your pages set up correctly and you can reach /blog/_slug, so it really is just a matter of passing the required params and converting them as needed. In blog.vue you would have a list of your posts and a click on something would navigate to the full article. That click event would trigger a method where you can manipulate the title and use it as a param. So if you have a 'Read More...' button you would assign #click="readMore(blog.title)" to that button.
Then in your methods you take the passed 'title' parameter, change it as you want, and trigger the route change.
methods: {
readeMore(title) {
let passedTitle = title.toLowerCase()
passedTitle = passedTitle.replace(" ", "-")
this.$router.push('/blog/' + passedTitle)
}
}
Then in your _slug.vue you take the passed param, change it back and use that to find your article.
export default {
asyncData({params, $axios }) {
let title = params.passedTitle.replace("-", " ")
let oldTitle = title.charAt(0).toUpperCase() + title.slice(1)
// make your query however you do, if with axios...
$axios.get('/posts', {
params: {
title: oldTitle
}
})
//or if its a vuex state item...
//let post = this.$store.state.posts.find((p) => p.title === oldTitle)
return post
},
}

Why *ngFor in Angular shows the new object first from the array of objects which is having .subscribe() method on in Ionic 3

I am new to Ionic 3 & Angular and ran into an issue with *ngFor and .subscribe() method. Please forgive me if it is an easy question. I tried to figure out the behaviour of http.get(..).map(..).subscribe() function when used along with *ngFor to maintain an array of objects and show the records to user using *ngFor on the .html template file but unable to know *ngFor's odd behaviour.
In my Ionic 3 App, I am getting the data using an API and storing it inside a component variable called "users" which is declared as below in component .ts file -
users: Array<any>;
I have below component function which gives me data for this users array -
addUser(count: number) {
this.http.get('https://randomuser.me/api/?results=' + count)
.map(data => data.json().results)
.subscribe(result => {
for (let val of result) {
this.users.push(val);
}
})
}
Initially, I get data for 10 users from the API using above component function by simply calling it inside my ngAfterViewInit() function like -
this.addUser(10);
This gives me 10 user record objects inside my users array which I show to the user using something like below in the view .html file -
<ion-card *ngFor="let user of users">
{{user.email}}
</ion-card>
At this time *ngFor puts the last array element at first in the view and shows the records in the descending order as the elements in the array starting from index 9 to 0.(LIFO order)
Now I start popping the last element from this users array using users.pop(); and push another element at the beginning at index 0 by shifting current elements using users.unshift(..) in below function and calling it as addNewUser(1); -
addNewUser(count: number) {
this.http.get('https://randomuser.me/api/?results=' + count)
.map(data => data.json().results)
.subscribe(result => {
for (let val of result) {
this.users.unshift(val);
}
})
}
At this moment, if we consider the first array which had 10 elements, the last object at index 9 had been removed and another element at index 0 has been added making the previous elements on index 0-8 to shift to index 1-9.
On doing so, my view gets updated which has *ngFor and surprisingly this time it shows the first element at first place which is actually on index 0 which is the one I recently put. This is opposite to the order earlier followed by *ngFor to render elements on the screen.
Why *ngFor in Ionic 3 view shows the recently inserted object element first from the array of objects which is dependent on the subscribe method .subscribe() method. I am really confused about this.
I really need to clear the concept of *ngFor and subscribe(). Please help me.
Note : The API mentioned above is publicly accessible for testing and you may call it to check the response structure if required.
Pasting a sample API response below on calling https://randomuser.me/api/?results=1 -
{
"results": [
{
"gender": "male",
"name": {
"title": "mr",
"first": "daniel",
"last": "stoll"
},
"location": {
"street": "9719 tannenweg",
"city": "cottbus/chosebuz",
"state": "bremen",
"postcode": 81443
},
"email": "daniel.stoll#example.com",
"login": {
"username": "greenleopard994",
"password": "chat",
"salt": "OUjisBdQ",
"md5": "8148d51998f3fef835a5f3979218c181",
"sha1": "131ae09d045b345efe36a330bf17a450b76f7de3",
"sha256": "94c3a362b5f516d0fb1d4e9dbb632d32d57b8886d5cc7bf0d5cedc99e7d55219"
},
"dob": "1957-04-26 22:07:14",
"registered": "2002-04-29 10:57:34",
"phone": "0556-4348870",
"cell": "0172-5116200",
"id": {
"name": "",
"value": null
},
"picture": {
"large": "https://randomuser.me/api/portraits/men/14.jpg",
"medium": "https://randomuser.me/api/portraits/med/men/14.jpg",
"thumbnail": "https://randomuser.me/api/portraits/thumb/men/14.jpg"
},
"nat": "DE"
}
],
"info": {
"seed": "8fd4afe85884c767",
"results": 1,
"page": 1,
"version": "1.1"
}
}
Refer this example showing my issue.
If you have a sorting issue with indexing and you think it's related.. you could work around the issue by assigning an index:
*ngFor="let user of users; let i = index"
and then reference the direct index value
users[i]
You should make a copy of that array. Editing array elements while looping them can lead to unexpected behaviour.

AngularJS custom directive within ng-repeat with dynamic attributes and two way binding

I'm banging my head on the wall over this for days and finally decided to post this question since I can't find an answer that matches what I'm trying to do.
Context: I'm building a dynamic form building platform that describes form elements in a JSON structure like this -
{
"name": "email",
"type": "email",
"text": "Your Email",
"model": "user.profile.email"
}
And then in the View I have a recursive ng-repeat that includes the field template like this -
<script type="text/ng-template" id="field.html">
<div ng-if="field.type === 'email'" class="{{field.class}}">
<p translate="{{field.text}}"></p>
<input type="{{field.type}}" name="{{field.name}}" class="form-control" dyn-model="{{field.model}}">
</div>
</script>
As you see, I use a custom directive dynModel to create the ng-model attribute with interpolated value of the model from the string value. So far do good.
Now I have a more complex scenario in which I have a collection of fields that can be added or removed by clicking on Add button or removeMe button. See below -
{
"name": "urls",
"type": "collection",
"text": "Your Profile URLs",
"model": "user.profile.urls",
"items": [
{
"name": "url",
"type": "url",
"text": "Facebook URL",
"model": "url"
},
{
"name": "url",
"type": "url",
"text": "Facebook URL",
"model": "url"
}
],
"action_button": {
"name": "add",
"type": "action",
"action": "addURL"
}
}
<div ng-if="field.type === 'collection'">
<button class="btn btn-info" dyn-click click-action="{{field.action_button.action}}" click-model="{{field.model}}">{{field.action_button.text}}</button>
<div dyn-ng-repeat="item in {{field.model}}" >
<div ng-repeat="field in field.items" ng-include src="'field.html'"></div>
</div>
</div>
As you'll notice, I have another custom directive that takes care of interpolation of {{field.model}} from the previous ng-repeat (not shown).
Now to the crux of the issue. As you see in the template, I have nested ng-repeats, the first one iterates through user.profile.urls and the second one iterates through the field parameters in JSON and creates the HTML tags, etc. One of those fields is a button (action_button) that is used to add more URLS to the list. When I click the button, I want it to trigger a function in my controller and effectively add a new child to the parent model (user.profile.urls). I then also want each URL, existing and new to have a remove button next to them that will be dynamic and will remove that particular item from the model.
If you see the code above, I have a custom directive dyn-click that reads in the
click-action="{{field.action_button.action}}"
That contains the function name (addURL) to be called that resides in my controller and the model
click-model="{{field.model}}"
(user.profile.urls) to which the new item is to be added. This is not working. The reason for this complexity is that I have multiple levels of nesting and at each level there are dynamic elements that need to be interpolated and bound. The directive dyn-click looks like this right now -
exports = module.exports = function (ngModule) {
ngModule.directive("dynClick",function() {
return {
restrict: 'A',
link: function(scope,element,attrs) {
$(element).click(function(e, rowid){
scope.clickAction(scope.clickModel, scope.$index);
});
}
};
});
};
With this code, when I click on the rendered form's Add button, the code in the $(element).click method above gets executed giving the following error -
Uncaught TypeError: undefined is not a function
I have tried a few different things with scope:{} in the dyn-click directive, with different errors and none of them have worked completely with two way binding of the model and calling the function as expected.
Help!
EDIT-1 - please see the comments:
$(element).click(function(e, rowid){
scope.$eval(attrs["clickAction"])(scope.$eval(attrs["clickModel"]), scope.$index);
});
EDIT-2: The plunker is here - http://plnkr.co/edit/DoacjRnO61g4IYodPwWu?p=preview. Still tweaking it to get it right, but you guys should be able to see the necessary pieces. Thanks!
EDIT-3: Thanks Sebastian. The new plunker is here - http://plnkr.co/edit/Z6ViT7scubMxa17SFgtx?p=preview . The issue with the field.items ng-repeat still exists. For some reason the inner ng-repeat is not being executed. Any ideas? Josep, Sebastian?

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