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To automatically install bower and its components, one must Specify the bower dependency in package.json: "dependencies": { "bower": "^1.7.9" } Use scripts to execute a postinstall command "scripts": { "postinstall": "./...

A daemon process executes a program in the background, usually without user interaction. The example below shows how to create a daemon and register a listener, which monitors all open applications. The main part is the function call NSRunLoop.mainRunLoop().run(), which starts the daemon. class MyO...

This serializer has some nice features that the default .net json serializer doesn't have, like Null value handling, you just need to create the JsonSerializerSettings : public static string Serialize(T obj) { string result = JsonConvert.SerializeObject(obj, new JsonSerializerSettings { NullVa...

You can make a URI parameter optional by adding a question mark to the route parameter. You can also specify a default value by using the form parameter=value. public class BooksController : Controller { // eg: /books // eg: /books/1430210079 [Route(“books/{isbn?}”)] public Act...

You can also apply the [Route] attribute on the controller level, capturing the action as a parameter. That route would then be applied on all actions in the controller, unless a specific [Route] has been defined on a specific action, overriding the default set on the controller. [RoutePrefix(“prom...

Route constraints let you restrict how the parameters in the route template are matched. The general syntax is {parameter:constraint}. For example: // eg: /users/5 [Route(“users/{id:int}”] public ActionResult GetUserById(int id) { … } // eg: users/ken [Route(“users/{name}”] public ActionRes...

Pretext This is an introduction to the Hello World program example on the Raspberry Pi written in C. The following example makes use of the command line interface and is set up as a step-by-step guide. Along with creating a Hello World program, the reader will be introduced to simple linux comman...

Provides the ratio of the current rows value to all the values within the window. --Data CREATE TABLE Employees (Name Varchar2(30), Salary Number(10)); INSERT INTO Employees Values ('Bob',2500); INSERT INTO Employees Values ('Alice',3500); INSERT INTO Employees Values ('Tom',2700); INSERT INTO...

Sending data back to the parent, to do this we simply pass a function as a prop from the parent component to the child component, and the child component calls that function. In this example, we will change the Parent state by passing a function to the Child component and invoking that function ins...

Another way of doing aggregations is by using the Mongo.Collection#rawCollection() This can only be run on the Server. Here is an example you can use in Meteor 1.3 and higher: Meteor.methods({ 'aggregateUsers'(someId) { const collection = MyCollection.rawCollection() const aggre...

Example: Customers who can create a post. Each customer can create multiple posts. As soon as customer creates the post, post will be under administrators review. Now we have to fetch the customers list who have all active posts by using sub-query. Note: If a customer has 5 post, among 5 posts if h...

Logs are very important. Recreate an error context can be sometimes very painful due to the lack of information about how and when the error occurred. This example shows: How to add user's data in the error logs How to add post parameters sent when an error occurred How to use WebPr...

Java Code import org.opencv.core.Mat; import org.opencv.core.MatOfRect; import org.opencv.core.Point; import org.opencv.core.Rect; import org.opencv.core.Scalar; import org.opencv.highgui.Highgui; import org.opencv.highgui.VideoCapture; import org.opencv.objdetect.CascadeClassifier; publ...

Use Nuget to install the Nancy and Nancy.Hosting.Self packages into the project. Instantiate a new NancyHost object and pass in the relevant URL using( var host = new NancyHost( hostConfiguration, new Uri( "http://localhost:1234" ) ) ) { host.Start(); Console.WriteLine( "Running o...

When you want to work with the data entries in arrays you first need to unwind the array. The unwind operation creates a document for each entry in the array. When you have lot's of documents with large arrays you will see an explosion in number of documents. { "_id" : 1, "item"...

_refreshListView(){ //Start Rendering Spinner this.setState({refreshing:true}) this.state.cars.push( {name:'Fusion',color:'Black'}, {name:'Yaris',color:'Blue'} ) //Updating the dataSource with new data this.setState({ dataSource: this.state.data...

RefreshControl is used inside a ScrollView or ListView to add pull to refresh functionality. at this example we will use it with ListView 'use strict' import React, { Component } from 'react'; import { StyleSheet, View, ListView, RefreshControl, Text } from 'react-native' class RefreshContr...

//Before: antipattern 3 global variables var setActivePage = function () {}; var getPage = function() {}; var redirectPage = function() {}; //After: just 1 global variable, no function collision and more meaningful function names var NavigationNs = NavigationNs || {}; N...

When multiple modules are involved, avoid proliferating global names by creating a single global namespace. From there, any sub-modules can be added to the global namespace. (Further nesting will slow down performance and add unnecessary complexity.) Longer names can be used if name clashes are an i...

Let us assume we have the following two DataFrames: In [7]: df1 Out[7]: A B 0 a1 b1 1 a2 b2 In [8]: df2 Out[8]: B C 0 b1 c1 The two DataFrames are not required to have the same set of columns. The append method does not change either of the original DataFrames. Inst...