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There are multiple threads in your code and you need to safely communicate between them. You can use a Queue from the queue library. from queue import Queue from threading import Thread # create a data producer def producer(output_queue): while True: data = data_computation() ...

Putting a & (ampersand) in front of an argument will pass it as the method's block. Objects will be converted to a Proc using the to_proc method. class Greeter def to_proc Proc.new do |item| puts "Hello, #{item}" end end end greet = Greeter.new %w(world l...

If you want to download an object from GCS that is publicly viewable, the simplest way is to use a web browser or a command line tool to fetch a URL with this pattern: https://storage.googleapis.com/bucketName/objectName. Example: https://storage.googleapis.com/pub/someOfTheTeam.jpg

The background-attachment property sets whether a background image is fixed or scrolls with the rest of the page. body { background-image: url('img.jpg'); background-attachment: fixed; } ValueDescriptionscrollThe background scrolls along with the element. This is default.fixedThe backgro...

The background-repeat property sets if/how a background image will be repeated. By default, a background-image is repeated both vertically and horizontally. div { background-image: url("img.jpg"); background-repeat: repeat-y; } Here's how a background-repeat: repeat-y looks lik...

Math.random(); produces an evenly distributed random number between 0 (inclusive) and 1 (exclusive) Example output: 0.22282187035307288 0.3948539895936847 0.9987191134132445

function randomMinMax(min:Number, max:Number):Number { return (min + (Math.random() * Math.abs(max - min))); } This function is called by passing a range of minimum and maximum values. Example: randomMinMax(1, 10); Example outputs: 1.661770915146917 2.5521070677787066 9.4362709657...

Custom views can also take custom attributes which can be used in Android layout resource files. To add attributes to your custom view you need to do the following: Define the name and type of your attributes: this is done inside res/values/attrs.xml (create it if necessary). The following file...

Destructuring allows us to refer to one key in an object, but declare it as a variable with a different name. The syntax looks like the key-value syntax for a normal JavaScript object. let user = { name: 'John Smith', id: 10, email: '[email protected]', }; let {user: userName, id: us...

LINQ is largely beneficial for querying collections (or arrays). For example, given the following sample data: var classroom = new Classroom { new Student { Name = "Alice", Grade = 97, HasSnack = true }, new Student { Name = "Bob", Grade = 82, HasSnack = false }, ...

Swift let webview = UIWebView(frame: CGRect(x: 0, y: 0, width: 320, height: 480)) Objective-C UIWebView *webview = [[UIWebView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)]; //Alternative way of defining frame for UIWebView UIWebView *webview = [[UIWebView alloc] init]; CGRect webviewFr...

The PrettyPrinter utility will 'pretty print' XML documents. The following code snippet pretty prints unformatted xml: import scala.xml.{PrettyPrinter, XML} val xml = XML.loadString("<a>Alana<b><c>Beth</c><d>Catie</d></b></a>") val formatt...

This is how to create a basic method that logs 'Hello World" to the console: - (void)hello { NSLog(@"Hello World"); } The - at the beginning denotes this method as an instance method. The (void) denotes the return type. This method doesn't return anything, so you enter void. ...

Abstract classes are classes that are meant to be inherited but avoid implementing specific methods, leaving behind only method signatures that subclasses must implement. Abstract classes are useful for defining and enforcing class abstractions at a high level, similar to the concept of interfaces ...

A Broadcast receiver is an Android component which allows you to register for system or application events. A receiver can be registered via the AndroidManifest.xml file or dynamically via the Context.registerReceiver() method. public class MyReceiver extends BroadcastReceiver { @Override ...

To add a method to a button, first create an action method: Objective-C -(void)someButtonAction:(id)sender { // sender is the object that was tapped, in this case its the button. NSLog(@"Button is tapped"); } Swift func someButtonAction() { print("Button is tapped...

You can easily transform every component in a clickable button using the MouseArea component. The code below displays a 360x360 window with a button and a text in the center; pressing the button will change the text: import QtQuick 2.0 Rectangle { width: 360 height: 360 Rectang...

To find all the files of a certain extension within the current path you can use the following find syntax. It works by making use of bash's built-in glob construct to match all the names having the .extension. find /directory/to/search -maxdepth 1 -type f -name "*.extension" To find ...

Subclass UINavigationController and then override these methods: In Objective-C: - (UIStatusBarStyle)preferredStatusBarStyle { return UIStatusBarStyleLightContent; } In Swift: override func preferredStatusBarStyle() -> UIStatusBarStyle { return .lightContent } Alternativel...

Since Git 1.7.12 it is possible to rebase down to the root commit. The root commit is the first commit ever made in a repository, and normally cannot be edited. Use the following command: git rebase -i --root