Tutorial by Examples: ha

accountStatusWithCompletionHandler

CKContainer.defaultContainer().accountStatusWithCompletionHandler { accountStatus, error in if accountStatus == .NoAccount { let alert = UIAlertController(title: "Sign in to iCloud", message: "Sign in to your iCloud account to write records. On the Home screen, l...

cloudkit • Determine if private database is available

Database management using Phalcon Model

A model for a new table can be created by running the following commend from the terminal root location: phalcon model <table-name> Let us take the Model Users. SELECT There are two default functions to do select operation in phalcon, find() and findFirst() findFirst() is used to get th...

phalcon • Database Management

Get debug SHA1 fingerprint

Open Android Studio Open Your Project Click on Gradle (From Right Side Panel, you will see Gradle Bar) Click on Refresh (Click on Refresh from Gradle Bar, you will see List Gradle scripts of your Project) Click on Your Project (Your Project Name form List (root)) Click on Tasks Click on andr...

Android • Google Maps API v2 for Android

How to compress image without size change

Get Compressed Bitmap from Singleton class: ImageView imageView = (ImageView)findViewById(R.id.imageView); Bitmap bitmap = ImageUtils.getInstant().getCompressedBitmap("Your_Image_Path_Here"); imageView.setImageBitmap(bitmap); ImageUtils.java: public class ImageUtils { public ...

Android • Image Compression

react on change of terminals window size

There is a signal WINCH ( WINdowCHange), which is fired when one resizes a terminal window. declare -x rows cols update_size(){ rows=$(tput lines) # get actual lines of term cols=$(tput cols) # get actual columns of term echo DEBUG terminal window has no $rows lines and is $cols chara...

Bash • Using "trap" to react to signals and system events

Polylines with alternative linejoins, linecaps and miterlimits

SVG • Polyline

Dashed line drawing with stroke-dasharray

SVG • Line

Reading and changing styles from a stylesheet

element.style only reads CSS properties set inline, as an element attribute. However, styles are often set in an external stylesheet. The actual style of an element can be accessed with window.getComputedStyle(element). This function returns an object containing the actual computed value of all the ...

DOM • Using CSS styles

config changes without restart

nginx -s reload

nginx • Nginx Configurations

What the classpath means: how searches work

The purpose of the classpath is to tell a JVM where to find classes and other resources. The meaning of the classpath and the search process are intertwined. The classpath is a form of search path which specifies a sequence of locations to look for resources. In a standard classpath, these places...

Java Language • The Classpath

INSERT with AUTO_INCREMENT + LAST_INSERT_ID()

When a table has an AUTO_INCREMENT PRIMARY KEY, normally one does not insert into that column. Instead, specify all the other columns, then ask what the new id was. CREATE TABLE t ( id SMALLINT UNSIGNED AUTO_INCREMENT NOT NULL, this ..., that ..., PRIMARY KEY(id) ); INSERT I...

MySQL • INSERT

Simple D3 Chart: Hello World!

Paste this code into an empty HTML file and run it in your browser. <!DOCTYPE html> <body> <script src="https://d3js.org/d3.v4.js"></script>  <script> //This code will visualize a data set as a simple scatt...

d3.js • Getting started with d3.js

Change opacity with "globalAlpha"

context.globalAlpha=0.50 You can change the opacity of new drawings by setting the globalAlpha to a value between 0.00 (fully transparent) and 1.00 (fully opaque). The default globalAlpha is 1.00 (fully opaque). Existing drawings are not affected by globalAlpha. // draw an opaque rectangle co...

html5-canvas • Compositing

Hadoop v2 Commands

appendToFile: Append single src, or multiple srcs from local file system to the destination file system. Also reads input from stdin and appends to destination file system. Keep the as - hdfs dfs -appendToFile [localfile1 localfile2 ..] [/HDFS/FILE/PATH..] cat: Copies source paths to stdout. ...

hadoop • Hadoop commands

Handling Errors

You can use the TextInputLayout to display error messages according to the material design guidelines using the setError and setErrorEnabledmethods. In order to show the error below the EditText use: TextInputLayout til = (TextInputLayout) findViewById(R.id.username); til.setErrorEnabled(true); ...

Android • TextInputLayout

Adding Character Counting

The TextInputLayout has a character counter for an EditText defined within it. The counter will be rendered below the EditText. Just use the setCounterEnabled() and setCounterMaxLength methods: TextInputLayout til = (TextInputLayout) findViewById(R.id.username); til.setCounterEnabled(true); til...

Android • TextInputLayout

Approximation of PI hand-crafting the #pragma omp reduction

int i; int n = 1000000; double area = 0; double h = 1.0 / n; #pragma omp parallel shared(n, h) { double thread_area = 0; // Private / local variable #pragma omp for for (i = 1; i <= n; i++) { double x = h * (i - 0.5); thread_area += (4.0 / (1.0 ...

openmp • OpenMP reductions

Waiting for two things to happen

var firstItem = fetch("/api1").then(x => x.json()); var secondItem = fetch("/api2").then(x => x.json()); Promise.all([firstItem, secondItem]).spread((first, second) => { // access both results here, both requests completed at this point });

bluebird • Promise.all

What are Namespaces?

The PHP community has a lot of developers creating lots of code. This means that one library’s PHP code may use the same class name as another library. When both libraries are used in the same namespace, they collide and cause trouble. Namespaces solve this problem. As described in the PHP referenc...

PHP • Namespaces

Password Hashing

Passwords should never be stored as plain text! They should be hashed with a randomly generated salt (to defend against rainbow table attacks) using a slow password hashing algorithm. A high number of iterations (> 10k) can be used to slow down brute force attacks. A delay of ~100ms is acceptable...

C# Language • Cryptography (System.Security.Cryptography)