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db.collection.createIndex() method is used to create a 2dsphere index. The blueprint of a 2dsphere index : db.collection.createIndex( { <location field> : "2dsphere" } ) Here, the location field is the key and 2dsphere is the type of the index. In the following example we are goi...

Once you've installed react and react-router, Its time to use both of them together. The syntax is very simple, you specify the url and the component you want to render when that url is opened <Route path="hello" component={ HelloComponent } /> This means when the url path is hell...

Using a small transparent image called empty.png public class MyPage : ContentPage { public Page() { if (Device.OS == TargetPlatform.Android) NavigationPage.SetTitleIcon(this, "empty.png"); } }

When we write an Web application in Grails, to deploy the application we need a "war" file that need's to be put in the servlet container (Tomcat etc). First goto the project directory : cd to_project_directory War file creation from command prompt : grails war 2.Its always r...

To add for instance a directory scripts to the distribution package: Add to the project a folder scripts On top of the build.sbt, add: import NativePackagerHelper._ In build.sbt, add a mapping to the new directory: mappings in Universal ++= directory("scripts") B...

Server side Meteor.methods({ getData() { return 'Hello, world!'; } }); Client side <template name="someData"> {{#if someData}} <p>{{someData}}</p> {{else}} <p>Loading...</p> {{/if}} </template> Template.someData.on...

You can add new extensions to require() by extending require.extensions. For a XML example: // Add .xml for require() require.extensions['.xml'] = (module, filename) => { const fs = require('fs') const xml2js = require('xml2js') module.exports = (callback) => { // ...

This is an example of Serial Document Middleware In this example, We will write a middleware that will convert the plain text password into a hashed password before saving it in database. This middleware will automatically kick in when creating new user or updating existing user details. FILENA...

Use Ember CLI to generate a new helper in your app: ember generate helper format-currency Then edit helpers/format-currency.js to contain the following: import Ember from 'ember'; export function formatCurrency([value, ...rest]) { const dollars = Math.floor(value / 100); const cents = va...

In Oracle 12g+ SELECT Id, Col1 FROM TableName ORDER BY Id OFFSET 5 ROWS; In earlier Versions SELECT Id, Col1 FROM (SELECT Id, Col1, row_number() over (order by Id) RowNumber FROM TableName) WHERE RowNumber > 20

- Initially check your E-Mail Settings In Odoo go to Settings --> Email . Enter the field values in "Incoming Mail Servers" & "Outgoing Mail Servers" Options.

Retrieves the information pertaining to the currently logged in user, and places it in the global variable $current_user This function does not accept any parameters. Usage: <?php wp_get_current_user(); ?> Example: <?php $current_user = wp_get_current_user(); echo 'Usernam...

<stock> <add> <item> <name>Milk</name> <quantity>2</quantity> </item> </add> </stock> Putting this body to an resource like /stocks/123 violates the idea behind REST. While this bod...

Defining an element with no content. <dom-module id="empty-element"> <template> <style> </style> </template> <script> Polymer({ is: 'empty-element', }); </script> </dom-module> And then you can ...

$color-purple-bg: #AF6EC4; $color-purple-border: #5D0C66; $color-yellow-bg: #E8CB48; $color-yellow-border: #757526; .tooltip { position: relative; &--arrow-down { @include pointer('bottom', 30px, ($color-purple-border, $color-purple-bg), 15px); } ...

A frequent reason why your read operation may not work is because your security rules reject the operation, for example because you're not authenticated (by default a database can only be accessed by an authenticated user). You can see these security rule violations in the logcat output. But it's e...

(ns so-doc.events (:require [goog.dom :as dom] [goog.events :as events])) (defn handle-click [event] ;an event object is passed to all events (js/alert "button pressed")) (events/listen (dom/getElement "button"); This is the dom element the event comes fro...

Large scale applications often need different properties when running on different environments. we can achieve this by passing arguments to NodeJs application and using same argument in node process to load specific environment property file. Suppose we have two property files for different enviro...

function positive() { return 0 } function negative() { return 1 }

Show how to use cv::VideoCapture with e.g. a webcam. Capturing frames from webcam and display it. Here is the example code: #include <iostream> #include "opencv2/highgui/highgui.hpp" #include "opencv2/imgproc/imgproc.hpp" #include "opencv2/core/core.hpp" ...