Category Archives: Tecnologías de la Información

Tecnologias de la Informacion

Angular2 – Authentication and Route protection

Module introduction We want allow only logged in users to modify recipes How Authentication works in SPAs In SPAs authentication is managed by tokens More about jWT JSON Web tokens: Creating a signup page and route We create a Sign up form page and his route “/signup”. All associated to a auth/signup.component Setting up […]

Angular2 – Making Http Requests

Introduction Traditional Web apps against SPAs Example App & Backend setup We use firebase to make a test database: NOTE: Keep in mind set database rules to get free access: { “rules”: { “.read”: “true”, “.write”: “true” } }   Sending requests (example POST) With the Angular Http class we can create Observables. But the […]

Angular2 – Handling forms: Reactive approach

Introduction to the Reactive Approach Form is created programmatically and synchronized with the DOM Reactive : Setup In the app.module we need to comment out FormsModule and add ReactiveFormsModule app.module.ts import { BrowserModule } from ‘@angular/platform-browser’; import { NgModule } from ‘@angular/core’; // import { FormsModule } from ‘@angular/forms’; import { ReactiveFormsModule } from ‘@angular/forms’; […]

Angular 2 – Using pipes to transform output and making http requests

Pipes are about transforming output Using Pipes Some pipes are coming built in in Angular: {{ server.instanceType | uppercase }} | {{ server.started | date}} Parametrizing pipes {{ server.started | date:’fullDate’ }} Where to learn more about pipes!?query=pipe For example , for the date pipe we can see all the options we have available: […]

Angular 2 – Handling forms

Regarding forms, what Angular does for us is giving us a object representation of the form in order to handle fetching data and form validation. And also we will be able to handle form submit without reloading the page (as it is a SPA). Two approaches There are two ways of handling forms with Angular. […]

Angular 2 – Observables

Observables are another way of handling async tasks. Angular2 use them a lot. Usually are objects wrapping some data source which emits events, such as button clicks , https requests, etc. Analyzing a Built in observable We already used observables when subscribing to changes int the route params: this.route.params.subscribe( (params: Params)=> { = +params[‘id’]; […]

Angular 2 – Routing

Setting up and loading routes We set up two routes: http://localhost:4200/page1 http://localhost:4200/page2 app.module.ts import { Routes, RouterModule } from ‘@angular/Router’; import { Page1Component } from ‘./page1/page1.component’; import { Page2Component } from ‘./page2/page2.component’; const appRoutes: Routes = [ // { path: ”, Page1Component}, { path: ‘page1’, component: Page1Component}, { path: ‘page2’, component: Page2Component} ]; … imports: […]

Angular 2 – Using services and dependency injection

Injecting a custom service into components A Service is created when we need a centralized component which serves some functionality to multiple components. Also we would expect to be a singleton instance. app.component.html <button type=”button” (click)=”testLoggingService(‘one’)” name=”button”>Test Logging Service One</button> <button type=”button” (click)=”testLoggingService(‘two’)” name=”button”>Test Logging Service Two</button> app.component.ts import { Component } from ‘@angular/core’; import […]

Angular 2 – Directives Deep dive

Attribute vs Structural Directives In attribute directives you never modify the DOM structure , just change some behaviour in the element where it is added to. I looks like a normal HTML attribute (with databinding or property binding). In Structural directives the DOM is modified. It also looks like a normal HTML attribute but it […]

Angular2 – Introduction Notes

Angular CLI Before install check latest nodejs version (>=v7.7.1) npm install -g @angular/cli Angular Command Line Interface for workflow commons tasks. More info in Create a new app skeleton: ng new my-first-app Init local development server: ng serve Integrating Bootstrap Install bootstrap npm package npm install –save bootstrap Edit .angular-cli.json: “styles”: [ “../node_modules/bootstrap/dist/css/bootstrap.min.css”, “styles.css” ], […]