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The ng-mouseenter and ng-mouseleave directives are useful to run events and apply CSS styling when you hover into or out of your DOM elements. The ng-mouseenter directive runs an expression one a mouse enter event (when the user enters his mouse pointer over the DOM element this directive resides i...

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...

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*/);

Placeholders allow you to feed values into a tensorflow graph. Aditionally They allow you to specify constraints regarding the dimensions and data type of the values being fed in. As such they are useful when creating a neural network to feed new training examples. The following example declares a ...

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", &...

Suppose we want to count how many counties are there in Texas: var counties = dbContext.States.Single(s => s.Code == "tx").Counties.Count(); The query is correct, but inefficient. States.Single(…) loads a state from the database. Next, Counties loads all 254 counties with all of the...

When you create a function in TypeScript you can specify the data type of the function's arguments and the data type for the return value Example: function sum(x: number, y: number): number { return x + y; } Here the syntax x: number, y: number means that the function can accept two argum...

TeX formulae can be inserted in the plot using the rc function import matplotlib.pyplot as plt plt.rc(usetex = True) or accessing the rcParams: import matplotlib.pyplot as plt params = {'tex.usetex': True} plt.rcParams.update(params) TeX uses the backslash \ for commands and symbols, whic...

You can search Docker Hub for images by using the search command: docker search <term> For example: $ docker search nginx NAME DESCRIPTION STARS OFFICIAL AUTOMATED nginx Official build of Nginx. ...

Dart has a robust async library, with Future, Stream, and more. However, sometimes you might run into an asynchronous API that uses callbacks instead of Futures. To bridge the gap between callbacks and Futures, Dart offers the Completer class. You can use a Completer to convert a callback into a Fut...

When defining a function, use {param1, param2, …} to specify named parameters: void enableFlags({bool bold, bool hidden}) { // ... } When calling a function, you can specify named parameters using paramName: value enableFlags(bold: true, hidden: false);

Often saving new data in an existing workbook using VBA will cause a pop-up question noting that the file already exists. To prevent this pop-up question, you have to suppress these types of alerts. Application.DisplayAlerts = False 'disable user prompt to overwrite file myWB.SaveAs FileNa...

The "factory default" number of worksheets created in a new Excel workbook is generally set to three. Your VBA code can explicitly set the number of worksheets in a new workbook. '--- save the current Excel global setting With Application Dim oldSheetsCount As Integer oldSheets...

Stackage is a repository for Haskell packages. We can add these packages to a stack project. Adding lens to a project. In a stack project, there is a file called stack.yaml. In stack.yaml there is a segment that looks like: resolver: lts-6.8 Stackage keeps a list of packages for every revision...

Example uses of $(document).ready(): Attaching event handlers Attach jQuery event handlers $(document).ready(function() { $("button").click(function() { // Code for the click function }); }); Run jQuery code after the page structure is created jQuery(function($) ...

When building a webserver with Express it's often required to serve a combination of dynamic content and static files. For example, you may have index.html and script.js which are static files kept in the file system. It is common to use folder named 'public' to have static files. In this case th...

A basic example of HTTP server. write following code in http_server.js file: var http = require('http'); var httpPort = 80; http.createServer(handler).listen(httpPort, start_callback); function handler(req, res) { var clientIP = req.connection.remoteAddress; var connectUsi...

app.js const readline = require('readline'); const fs = require('fs'); var file = 'path.to.file'; var linesCount = 0; var rl = readline.createInterface({ input: fs.createReadStream(file), output: process.stdout, terminal: false }); rl.on('line', function (line) { linesCo...

NodeJS executes the module only the first time you require it. Any further require functions will re-use the same Object, thus not executing the code in the module another time. Also Node caches the modules first time they are loaded using require. This reduces the number of file reads and helps to...

The following example shows how to merge two arrays into one associative array, where the key values will be the items of the first array, and the values will be from the second: $array_one = ['key1', 'key2', 'key3']; $array_two = ['value1', 'value2', 'value3']; $array_three = array_combine($ar...