Tutorial by Examples: el

Believe it or not, the Label is one of the most crucial yet underappreciated View classes not only in Xamarin.Forms, but in UI development in general. It is seen as a rather boring line of text, but without that line of text it would be very difficult to convey certain ideas to the user. Label co...

An EntryCell is a Cell that combines the capabilities of a Label and an Entry. The EntryCell can be useful in scenarios when building some functionality within your application to gather data from the user. They can easily be placed into a TableView and be treated as a simple form. XAML <Ent...

A SwitchCell is a Cell that combines the capabilities of a Label and an on-off switch. A SwitchCell can be useful for turning on and off functionality, or even user preferences or configuration options. XAML <SwitchCell Text="Switch It Up!" /> Code var switchCell = new Switch...

A TextCell is a Cell that has two separate text areas for displaying data. A TextCell is typically used for information purposes in both TableView and ListView controls. The two text areas are aligned vertically to maximize the space within the Cell. This type of Cell is also commonly used to dis...

An ImageCell is exactly what it sounds like. It is a simple Cell that contains only an Image. This control functions very similarly to a normal Image control, but with far fewer bells and whistles. XAML <ImageCell ImageSource="http://d2g29cya9iq7ip.cloudfront.net/content/imag es/company...

You can consider a ViewCell a blank slate. It is your personal canvas to create a Cell that looks exactly the way you want it. You can even compose it of instances of multiple other View objects put together with Layout controls. You are only limited by your imagination. And maybe screen size. X...

First off, let's assume this is your initial model, inside an application called discography: from django.db import models class Album(models.Model): name = models.CharField(max_length=255) artist = models.CharField(max_length=255) Now, you realize that you want to use a ForeignKey ...

Akka Streams allows you to easily create a stream leveraging the power of the Akka framework without explicitly defining actor behaviors and messages. Every stream will have at least one Source (origin of the data) and at least one Sink (destination of the data). import akka.actor.ActorSystem impo...

DECLARE @ID AS INT; SET @ID = (SELECT MIN(ID) from TABLE); WHILE @ID IS NOT NULL BEGIN PRINT @ID; SET @ID = (SELECT MIN(ID) FROM TABLE WHERE ID > @ID); END

RwLocks allow a single producer provide any number of readers with data while preventing readers from seeing invalid or inconsistent data. The following example uses RwLock to show how a single producer thread can periodically increase a value while two consumers threads are reading the value. use...

You can COPY table and paste it into a file. postgres=# select * from my_table; c1 | c2 | c3 ----+----+---- 1 | 1 | 1 2 | 2 | 2 3 | 3 | 3 4 | 4 | 4 5 | 5 | (5 rows) postgres=# copy my_table to '/home/postgres/my_table.txt' using delimiters '|' with null as 'null_s...

If you're Using VueJS2 and like to use JSX along with it. In this case,to use the slot, the solution with example is below.We have to use this.$slots.default It's almost like this.props.children in React JS. Component.js : export default { render(h) { //eslint-disable-line return ( ...

Schema changes: You will need to define a new field type in your solr schema file and then you can create fields of that type. Example schema snippet: <!-- Source: solr/example/.../conf/schema.xml --> <?xml version="1.0" encoding="UTF-8" ?> <schema name="a...

Let's get some theoretical knowledge before moving to the example. There are three important terms being used here Analyzers, Tokenizers, and Filters. To create such custom field you will need to create an analyzer with one tokenizer and one or more filters. As mentioned here, you can have only one ...

import { NgModule, CUSTOM_ELEMENTS_SCHEMA } from '@angular/core'; import { CommonModule } from '@angular/common'; import { AboutComponent } from './about.component'; @NgModule({ imports: [ CommonModule ], declarations: [ AboutComponent ], exports: [ AboutComponent ], schemas...

Go to the [https://developers.facebook.com/](https://developers.facebook.com/) and create your app. Click Add product and choose Facebook Login

When calling driver.Navigate().GoToUrl(url);, the code execution stops until the page is fully loaded. This is sometimes unnecessary when you just want to extract data. Note: The code samples below could be considered hacks. There is no "official" way of doing this. Create a new thread...

DELETE FROM <SCHEMA_NAME>.<Table_NAME> WHERE ctid NOT IN ( SELECT MAX(ctid) FROM <SCHEMA_NAME>.<TABLE_NAME> GROUP BY <SCHEMA_NAME>.<TABLE_NAME>.* ) ;

I need to query all the details from virtual machine and update into the MongoDB. Which require the output look like this. { "_id" : ObjectId("5800509f23888a12bccf2347"), "ResourceGrp" : "XYZZ-MachineGrp", "ProcessTime" : ISODate(&q...

$MachinesList # Array $ResourceList # Array $MachineTags # Array pseudo code $mongoDriverPath = 'C:\Program Files (x86)\MongoDB\CSharpDriver 1.7'; Add-Type -Path "$($mongoDriverPath)\MongoDB.Bson.dll"; Add-Type -Path &qu...