Tutorial by Examples: re

Creating DTOs (POJOs/POCOs)

Data classes in kotlin are classes created to do nothing but hold data. Such classes are marked as data: data class User(var firstname: String, var lastname: String, var age: Int) The code above creates a User class with the following automatically generated: Getters and Setters for all prope...

Kotlin • Idioms

Dispatching Clack requests

Because a clack request is represented as a plist, we can use pattern matching as the entry point to the clack app as a way to route request to their appropriate controllers (defvar *app* (lambda (env) (match env ((plist :request-method :get :request-uri uri) (...

common-lisp • Pattern matching

Create a new Rails app with a non-standard database adapter

Rails is shipped by default with ActiveRecord, an ORM (Object Relational Mapping) derived from the pattern with the same name. As an ORM, it is built to handle relational-mapping, and more precisely by handling SQL requests for you, hence the limitation to SQL databases only. However, you can stil...

Ruby on Rails • Getting started with Ruby on Rails

Add header/footer to a RecyclerView

This is a sample adapter code. public class SampleAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> { private static final int FOOTER_VIEW = 1; // Define a view holder for Footer view public class FooterViewHolder extends ViewHolder { public FooterViewHolder(View ite...

Android • RecyclerView

README file

If your project doesn't have README.md, GitHub may parse README.rdoc to display details. If it has both, it will use README.md, silently ignoring rdoc. A README file may include- Project Title Describe briefly about your project. You may also provide project's website link, badges, community ...

github • Getting started with github

Coding style and recommendations

Content has been moved back to good 'ol Servlets wiki page

servlets • Getting started with servlets

Use Trigger to manage a "Recycle Bin" for deleted items

CREATE TRIGGER BooksDeleteTrigger ON MyBooksDB.Books AFTER DELETE AS INSERT INTO BooksRecycleBin SELECT * FROM deleted; GO

SQL • Triggers

Link CoreLocation Framework

Import the CoreLocation module in your classes that use CoreLocation functionality. //Swift import CoreLocation //Objective-C #import <CoreLocation/CoreLocation.h>

iOS • Core Location

Request Permission to Use Location Services

Check the app's authorization status with: //Swift let status: CLAuthorizationStatus = CLLocationManager.authorizationStatus() //Objective-C CLAuthorizationStatus status = [CLLocationManager authorizationStatus]; Test the status against the follow constants: //Swift switch status { case ...

iOS • Core Location

Copy to clipboard from textarea using execCommand("copy")

Example: <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title></title> </head> <body> <textarea id="content"></textarea> <input type="button" id="copy...

JavaScript • execCommand and contenteditable

Moving scroll when UITextView becomes first responder

Observe the notifications UIKeyboardWillShowNotification and UIKeyboardWillHideNotification, update the scrollView content insets according to keyboard height, then scroll to the focused control. - (void)viewDidLoad { [super viewDidLoad]; // register for keyboard notifications [[...

iOS • UITextField

Reading a cookie

In order to read a cookie use the following code: $value = \Yii::$app->getRequest()->getCookies()->getValue('my_cookie'); Note: this code allows read cookies that has been set using cookie component (because it signs all cookies by default). Therefore if you add/update cookie using JS c...

yii2 • Cookies

HTTP requests and responses

HTTP describes how an HTTP client, such as a web browser, sends an HTTP request via a network to an HTTP server, which then sends an HTTP response back to the client. The HTTP request is typically either a request for an online resource, such as a web page or image, but may also include additiona...

HTTP • Getting started with HTTP

Custom renderer for ListView

Custom Renderers let developers customize the appearance and behavior of Xamarin.Forms controls on each platform. Developers could use features of native controls. For example, we need to disable scroll in ListView. On iOS ListView is scrollable even if all items are placed on the screen and user s...

Xamarin.Forms • Custom Renderers

Built-In Directives Cheat Sheet

ng-app Sets the AngularJS section. ng-init Sets a default variable value. ng-bind Alternative to {{ }} template. ng-bind-template Binds multiple expressions to the view. ng-non-bindable States that the data isn't bindable. ng-bind-html Binds inner HTML property of an HTML element....

AngularJS • Built-in directives

Set up Retrofit and RxJava

Retrofit2 comes with support for multiple pluggable execution mechanisms, one of them is RxJava. To use retrofit with RxJava you first need to add the Retrofit RxJava adapter to your project: compile 'com.squareup.retrofit2:adapter-rxjava:2.1.0' then you need to add the adapter when building yo...

rx-java • Retrofit and RxJava

Making serial requests

RxJava is handy when making serial request. If you want to use the result from one request to make another you can use the flatMap operator: api.getRepo(repoId).flatMap(repo -> api.getUser(repo.getOwnerId()) .subscribe(/*do something with the result*/);

rx-java • Retrofit and RxJava

Making parallel requests

You can use the zip operator to make request in parallel and combine the results eg: Observable.zip(api.getRepo(repoId1), api.getRepo(repoId2), (repo1, repo2) -> { //here you can combine the results }).subscribe(/*do something with the result*/);

rx-java • Retrofit and RxJava

Using std::move to reduce complexity from O(n²) to O(n)

C++11 introduced core language and standard library support for moving an object. The idea is that when an object o is a temporary and one wants a logical copy, then its safe to just pilfer o's resources, such as a dynamically allocated buffer, leaving o logically empty but still destructible and co...

C++ • Move Semantics

Compare operation with collections - Create collections

Compare operation with collections - Create collections 1. Create List DescriptionJDKguavags-collectionsCreate empty listnew ArrayList<>()Lists.newArrayList()FastList.newList()Create list from valuesArrays.asList("1", "2", "3")Lists.newArrayList("1", &...

Java Language • Alternative Collections