Tutorial by Examples: v

Some times you see a signal is emitted in sender thread but connected slot doesn't called (in other words it doesn't receive signal), you have asked about it and finaly got that the connection type Qt::DirectConnection would fix it, so the problem found and everything is ok. But generaly this is ba...

Native implementations The <template> element is implemented in every modern browsers: Chrome, Edge, Firefox, Opera, Safari, ... Custom Elements customElements.define(), Shadow DOM attachShadow() and HTML Imports <link rel="import"> are implemented in the latest ver...

Show or hide invisible characters To show invisible characters: :set list To hide invisible characters: :set nolist To toggle between showing and hiding invisible characters: :set list! Default symbol characters SymbolCharacter^ITab$New Line Customize symbols To set the tab characte...

import org.apache.spark.sql.functions._ // Create a function that uses the content of the column inside the dataframe val code = (param: String) => if (param == "myCode") 1 else 0 // With that function, create the udf function val myUDF = udf(code) // Apply the udf to a column in...

This a sample code which will show you how you can create dynamic code which will generate a bootstrap model at run time. This also includes deciding modal title body content and buttons in footer. HTML code <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css&...

You can test sending messages using the FCM REST API by sending a request through cURL. curl --header "Authorization: key=<API_KEY>" \ --header Content-Type:"application/json" \ https://fcm.googleapis.com/fcm/send \ -d "{\"registration_ids...

How do you detect them? If the same variable/resource/memory location is accessible by multiple threads and at least of the thread is changing the value of variable/resource/memory location, then Race Condition can occurred. Because if a thread is changing the value of variable/resource/memory ...

trash is a minimalistic vendoring tool that you configure with vendor.conf file. This example is for trash itself: # package github.com/rancher/trash github.com/Sirupsen/logrus v0.10.0 github.com/urfave/cli v1.18.0 github.com/cloudfoundry-incubat...

constexpr const size_t addressSize = sizeof(sockaddr_in); constexpr const uint16_t defaultPort = 80; // The port you want to use int serverSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); sockaddr_in serverAddress, clientAddress; memset(&serverAddress, 0, addressSize); serverAddress....

To display current version, we can use VERSION from @angular/core package. import { Component, VERSION } from '@angular/core'; @Component({ selector: 'my-app', template: `<h1>Hello {{name}}</h1> <h2>Current Version: {{ver}}</h2> `, }) export class AppCompone...

Binary Literals: The integral types (byte, short, int, and long) can also be expressed using the binary number system. To specify a binary literal, add the prefix 0b or 0B to the number. Strings in switch Statements: You can use a String object in the expression of a switch statement The try-wit...

Lambda Expressions, a new language feature, has been introduced in this release. They enable you to treat functionality as a method argument, or code as data. Lambda expressions let you express instances of single-method interfaces (referred to as functional interfaces) more compactly. Method r...

Nested if()...else statements take more execution time (they are slower) in comparison to an if()...else ladder because the nested if()...else statements check all the inner conditional statements once the outer conditional if() statement is satisfied, whereas the if()..else ladder will stop condit...

If you want to investigate why you are maxing out your DTUs, add other metrics to the performance graph to see which metric is dominiationg your DTU usage. In this example, the DTU usage is clearly dominiated by the CPU usage

In the same way as in Open Terminal in current Xcode project folder example, you can add clear of derived data folder with hotkey. Create custom behavior (follow the steps in Open Terminal in current Xcode project folder). But use another script. Script text: #!/bin/bash rm -rf $HOME"/Lib...

<canvas id = "canvas" height='400' width='500'></canvas> var canvas = new fabric.Canvas(document.getElementById('canvas')); console.log(JSON.stringify(canvas)); // '{"objects":[],"background":""}' canvas.add(new fabric.Rect({ left: 10, ...

Refer to this original Post by e.James According to Apple's NSInvocation class reference: An NSInvocation is an Objective-C message rendered static, that is, it is an action turned into an object. And, in a little more detail: The concept of messages is central to the objective-c philosophy....

First declare a property like this in the ViewController @property (nonatomic) UIRefreshControl *refreshControl; Later in the viewDidLoad() set up the refreshControl as given below: self.refreshControl = [[UIRefreshControl alloc]init]; [self.tableView addSubview:self.refreshControl]; [self.re...

Navigator works for both IOS and android. import React, { Component } from 'react'; import { Text, Navigator, TouchableHighlight } from 'react-native'; export default class NavAllDay extends Component { render() { return ( <Navigator initialRoute={{ title: 'Awesome Sc...

One common pitfall is to try and use this in a nested function or an object, where the context has been lost. document.getElementById('myAJAXButton').onclick = function(){ makeAJAXRequest(function(result){ if (result) { // success this.className = 'success'; } }) }...