https://github.com/electron/electron
https://github.com/angular/angular.js/
https://github.com/pckurdu/Build-Application-Using-Firebase-With-Electronjs-Part-3
add() functiononSnapshot() and get() functionsdocs propery and data() functioninnerHTML and getElementById functions in javascriptHello to everyone,
We are at the end of the articles I described the process of creating a desktop application using firebase.
We have performed electronjs installation in previous tutorials and we have done angular routing settings and also we have performed login and signup using firebase authentication.
Once we've logged in, we can access and modify certain data in application. We must store this data in a database. Firebase provides database and database services to store our data. This database is called cloud firestore and we will use this database for our desktop application.
We'll create a dashboard page and we'll only give it access when it's authentice. When the user accesses the dashboard page, he/she will be able to add articles and view these articles. We will enter the title and content of the article on the application and create a collection of articles and add the data to the documentation.
This tutorial consists of 3 parts:
In the first part, we will create the dashboard page and create the form elements to enter the title and content of the articles, and we will also edit them using bootstrap.
In the second part, we enter these values on the cloud firestore.
In the third part, we list the documents on the cloud firestore.
Let's start!
The dashboard page is a page that the user can see by loging in. This page will be the data entry into the database.
The user will enter the title and content of the articles in the form field and this information will be saved in the cloud firestore so we have to create two input for the user to enter the article title and article content.
These values must also be displayed on the screen because I want to explain post the data in firestore and get the data list in firestore. So I would like to open a field where I will show you the article lists.
<div class="container">
<form>
<div class="form-group">
<label for="title">Article Title</label>
<input type="text" class="form-control" id="title" ng-model="title" />
</div>
<div class="form-group">
<label for="content">Article Content</label>
<input type="text" class="form-control" id="content" ng-model="content" />
</div>
<button type="submit" class="btn btn-warning" ng-click="add()">Add</button>
</form><br/>
<h3>Article List</h3>
<div>
<ul class="list-group" id="ul">
</ul>
</div>
</div>
We've added two div that use the form-group classes, and we've defined the inputs between these divs.
The important thing here is the values of the ng-model attributes, because with the help of these values, we will capture the data entered in the inputs. In addition, the button added to the button will inform us that the button clicked.
We divided the board page into two and added the data to the user in the first part, in the second part, we have defined the ul label to show this added data. We do not define the li tags inside the ul tag because will create the li tags on the controller page and upload them to the ul tag.
To access the elements on the dashboard page we need to create a controller for this page. So we can access the add() function and add the data to firestore.
app.controller('dashboardCtrl',function($rootScope,$scope,$location){
if($rootScope.auth==true){//checking user login.
}
}
Since I'll use $scope, $rootScope and $location objects in the dashboardCtrl, I've defined these objects in the cotroller function.
When the user loged in to loginCtrl, we set the $rootScope.auth object to true. So that we can determine that the user is logged in. In dashboardCtrl, we have to check this auth object before activating the dashboard page.
As we have done the necessary checks, we can now write our code to add our data. We need to write all the codes in the if block, which we check the auth object.
$scope.add=function(){
db.collection('articles').add({//A collection of articles is being created and a document is added.
title:$scope.title,
content:$scope.content
}).then(()=>{//success
console.log("Article successfully added");
}).catch(err=>{//unsuccessful
console.log(err.message);
})
}
The $scope.add function is the function that will be triggered when the button is clicked.
We have previously defined the db variable. This represents the variable firestore. We can add collection to firestore with collection included in db object. With the add() function in the collection, we can add a document to the firestore.
The add() function takes the object into it and resends the result to us. If the data insertion is successful with the then() function, we can capture the result. If an error occurs during data insertion, we can find this error with the catch() function.
After clicking the Add button, this data is added to the firebase.
Initially did not have a collection of articles and was created when we click the add button. If we run the application again and add the another article again, it will add the document in the existing articles collection.
In this section we will show the firestore data on the application.
var ul=document.getElementById('ul');//ul element to be added to the article list is captured.
db.collection('articles').onSnapshot(snap=>{//Instant data is captured with onsnapshot
console.log(snap.docs);
})
We created the ul tag on dashboard.html.With the getElementById() function, we can access this entire tag.
The onSnapshot() function allows us to access the documents in the collection instantly. Opens a channel between firestore and the application and provides continuous control of a change. Another method of access to data is the get() function. With the get() function, access to the data is provided, but the application cannot see this change when there is a change in firestore after access.
When we print the snap.docs information to the console, we get the following result.
then we can capture articles from this data.
var articles=snap.docs;//all documents in articles collection
if(articles.length){
let html='';//I will add all li tags into html
articles.forEach(art=>{
//console.log(belge);
var a=art.data();//title and content fields of the document
console.log(a);
//each article is written to the variable li.
var li=`${a.title}---${a.content} `;
html +=li;
});
ul.innerHTML=html;//Add li elements into ul
}
We return to all documents with forEach and access the documents with the data() function. after this process a variable has the title and content information of the document.We can define this information in a li tag, I define the class property for using Bootstrap. After the forEach process is finished, the data in the database is made up of a html variables.
Finally, we can define this data to the ul tag using the innerHTML property.
Result: