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A downcast can be used to make use of a subclass's code and data inside of a function taking a parameter of its superclass. class Rat { var color = "white" } class PetRat: Rat { var name = "Spot" } func nameOfRat(🐭: Rat) -> String { guard let petRat = ...

To add a value to a WeakSet, use the .add() method. This method is chainable. const obj1 = {}, obj2 = {}; const weakset = new WeakSet(); weakset.add(obj1).add(obj2);

Given the 3 points of a quadratic curve the following function returns the length. function quadraticBezierLength(x1,y1,x2,y2,x3,y3) var a, e, c, d, u, a1, e1, c1, d1, u1, v1x, v1y; v1x = x2 * 2; v1y = y2 * 2; d = x1 - v1x + x3; d1 = y1 - v1y + y3; e = v1x - 2 * x1; ...

This code adds outwardly increasing shadows to an image to create a "sticker" version of the image. Notes: In addition to being an ImageObject, the "img" argument can also be a Canvas element. This allows you to stickerize your own custom drawings. If you draw text on the Can...

Once shadowing is turned on, every new drawing to the canvas will be shadowed. Turn off further shadowing by setting context.shadowColor to a transparent color. // start shadowing context.shadowColor='black'; ... render some shadowed drawings ... // turn off shadowing. context.shadowColor=...

Warning! Apply shadows sparingly! Applying shadowing is expensive and is multiplicatively expensive if you apply shadowing inside an animation loop. Instead, cache a shadowed version of your image (or other drawing): At the start of your app, create a shadowed version of your image in a secon...

The traditional use of shadowing is to give 2-dimensional drawings the illusion of 3D depth. This example shows the same "button" with and without shadowing var canvas=document.createElement("canvas"); var ctx=canvas.getContext("2d"); document.body.appendChild(can...

Canvas does not have CSS's inner-shadow. Canvas will shadow the outside of a filled shape. Canvas will shadow both inside and outside a stroked shape. But it's easy to create inner-shadows using compositing. Strokes with an inner-shadow To create strokes with an inner-shadow, use destinat...

INSERT INTO Invoices [ /* column names may go here */ ] VALUES (123, '1234abc', '2016-08-05 20:18:25.770', 321, 5, '2016-08-04'); Column names are required if the table you are inserting into contains a column with the IDENTITY attribute. INSERT INTO Invoices ([ID], [Num], [DateTime], [Tota...

Create a custom BitmapImageViewTarget to load the image into: public class CircularBitmapImageViewTarget extends BitmapImageViewTarget { private Context context; private ImageView imageView; public CircularBitmapImageViewTarget(Context context, ImageView imageView) { ...

By adding a header with content type as JSON: <?php $result = array('menu1' => 'home', 'menu2' => 'code php', 'menu3' => 'about'); //return the json response : header('Content-Type: application/json'); // <-- header declaration echo json_encode($result, true); // <--- e...

As always, you need to make sure you have the required permissions. public class MainActivity extends AppCompatActivity implements LocationListener{ private LocationManager mLocationManager = null; HandlerThread mLocationHandlerThread = null; Looper mLocationHandlerLooper = null; ...

Here are simplified steps (based on the official documentation) required to create a Firebase project and connect it with an Android app. Add Firebase to your app Create a Firebase project in the Firebase console and click Create New Project. Click Add Firebase to your Android app and fol...

SQL Server 2008 R2 SET TRANSACTION ISOLATION LEVEL READ COMMITTED This isolation level is the 2nd most permissive. It prevents dirty reads. The behavior of READ COMMITTED depends on the setting of the READ_COMMITTED_SNAPSHOT: If set to OFF (the default setting) the transaction uses shared l...

Dirty reads (or uncommitted reads) are reads of rows which are being modified by an open transaction. This behavior can be replicated by using 2 separate queries: one to open a transaction and write some data to a table without committing, the other to select the data to be written (but not yet com...

FOREIGN KEY constraint can be added on existing tables that are still not in relationship. Imagine that we have Company and Employee tables where Employee table CompanyId column but don't have foreign key relationship. ALTER TABLE statement enables you to add foreign key constraint on an existing c...

FOREIGN KEY columns with constraint can be added on existing tables that are still not in relationship. Imagine that we have Company and Employee tables where Employee table don't have CompanyId column. ALTER TABLE statement enables you to add new column with foreign key constraint that references ...

A commonly used utility library is Lodash. To install it into your Aurelia CLI driven application first you need to install it using Npm. npm install lodash --save Now in your preferred IDE/code editor open up the following file in your project directory: aurelia_project/aurelia.json and scroll do...

Rather than use clearRect which makes all pixels transparent you may want a background. To clear with a gradient // create the background gradient once var bgGrad = ctx.createLinearGradient(0,0,0,canvas.height); bgGrad.addColorStop(0,"#0FF"); bgGrad.addColorStop(1,"#08F"); ...

Right click on the solution, Add new project From the Test section, select an Unit Test Project Pick a name for the assembly - if you are testing project Foo, the name can be Foo.Tests Add a reference to the tested project in the unit test project references