Tutorial by Examples: le

To load a class we first need to define it. The class is defined by the ClassLoader. There's just one problem, Oracle didn't write the ClassLoader's code with this feature available. To define the class we will need to access a method named defineClass() which is a private method of the ClassLoader....

{ "title": "Person", "type": "object", "properties": { "firstName": { "type": "string" }, "lastName": { "type": "string" ...

shared.service.ts: import { Injectable } from '@angular/core'; import { Headers, Http } from '@angular/http'; import 'rxjs/add/operator/toPromise'; import { Observable } from 'rxjs/Observable'; import { Observable } from 'rxjs/Rx'; import {Subject} from 'rxjs/Subject'; @Injectable(...

To create a component we add @Component decorator in a class passing some parameters: providers: Resources that will be injected into the component constructor selector: The query selector that will find the element in the HTML and replace by the component styles: Inline styles. NOTE: DO NOT us...

Templates are HTML files that may contain logic. You can specify a template in two ways: Passing template as a file path @Component({ templateUrl: 'hero.component.html', }) Passing a template as an inline code @Component({ template: `<div>My template here</div>`, }) Tem...

Let's assume we have a Dogs application, then our model will be a Dog class. DatabaseReference reference = FirebaseDatabase.getInstance().getReference().child("dogs"); This is how to send a Dog to the database, a new unique dog and set the dog with the key. String key = reference.push...

A module is a class with the @NgModule decorator. To create a module we add @NgModule passing some parameters: bootstrap: The component that will be the root of your application. This configuration is only present on your root module declarations: Resources the module declares. When you add a ne...

Modules can be nested by using the imports parameter of @NgModule decorator. We can create a core.module in our application that will contain generic things, like a ReservePipe (a pipe that reverse a string) and bundle those in this module: import { CommonModule } from '@angular/common'; import {...

The model view controller is a very common design pattern that has been around for quite some time. This pattern focuses on reducing spaghetti code by separating classes into functional parts. Recently I have been experimenting with this design pattern in Unity and would like to lay out a basic exam...

Here is how to create your own singleton class for toast messages, If your application need to show success, warning and the danger messages for different use cases you can use this class after you have modified it to your own specifications. public class ToastGenerate { private stati...

In this example, base class Singleton provides getMessage() method that returns "Hello world!" message. It's subclasses UppercaseSingleton and LowercaseSingleton override getMessage() method to provide appropriate representation of the message. //Yeah, we'll need reflection to pull this ...

Grouping with the data.table package is done using the syntax dt[i, j, by] Which can be read out loud as: "Take dt, subset rows using i, then calculate j, grouped by by." Within the dt statement, multiple calculations or groups should be put in a list. Since an alias for list() is .(), bo...

To send a file and form data in single request, content should have multipart/form-data type. using System; using System.Collections.Generic; using System.IO; using System.Net; using System.Threading.Tasks; public async Task<string> UploadFile(string url, string filename, Diction...

Use the following flowchart to choose the right Collection for the job. This flowchart was based off [http://i.stack.imgur.com/aSDsG.png).

data.service.ts: import { Injectable } from '@angular/core'; import { Http } from '@angular/http'; import 'rxjs/add/operator/map'; @Injectable() export class DataService { constructor(private http: Http) { } fetchData(){ return this.http.get('https://dinstruct-d4b62.firebaseio....

This example requires FormsModule and ReactiveFormsModule. Please import them in your application/module. import {FormsModule, ReactiveFormsModule} from '@angular/forms'; input-form-example.html <form class="example-form" (ngSubmit)="submit(addForm.value)" [formGroup]=&qu...

This example requires FormsModule and ReactiveFormsModule. Please import them in your application/module. import {FormsModule, ReactiveFormsModule} from '@angular/forms'; autocomplete-overview-example.html: <md-input-container> <input mdInput placeholder="State" [mdAutocom...

To find the word foo in the file bar : grep foo ~/Desktop/bar To find all lines that do not contain foo in the file bar : grep –v foo ~/Desktop/bar To use find all words containing foo in the end (WIldcard Expansion): grep "*foo" ~/Desktop/bar

This is continuation of previous example. Cascading DropDown for country's city name. This method will be called by Jquery when user is done with country selection in parent dropdown. I have followed MVC concept and provided the basic approach for cascading dropdown. Ajax will call GetCityName met...

import csv #------ We will write to CSV in this function ------------ def csv_writer(data, path): #Open CSV file whose path we passed. with open(path, "wb") as csv_file: writer = csv.writer(csv_file, delimiter=',') for line in data: ...