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First it is important to understand that the Core Data Model is the *.xcdatamodeld file. You will notice you have not entities. You will have to create one yourself. At the bottom of Xcode you will notice a button that says "Add Entity" click it and you will have a new entity in the ...

Under the attributes section you add the attributes to your model. This button is a plus located at the bottom of the section. You can add any attributes that are relevant to your app. You have several options of types to choose from ranging from Booleans to Dates and more. The Inspector panel also ...

Relationships are relationship between entities that can be one-to-one or one-to-many. Creating a relationship is not needed to use Core Data.

To add a value to a Set, use the .add() method: mySet.add(5); If the value already exist in the set it will not be added again, as Sets contain unique values. Note that the .add() method returns the set itself, so you can chain add calls together: mySet.add(1).add(2).add(3);

Hibernate has some strategies of inheritance. The JOINED inheritance type do a JOIN between the child entity and parent entity. The problem with this approach is that Hibernate always bring the data of all involved tables in the inheritance. Per example, if you have the entities Bicycle and Mounta...

System.Threading.Timer - Simplest multithreaded timer. Contains two methods and one constructor. Example: A timer calls the DataWrite method, which writes "multithread executed..." after five seconds have elapsed, and then every second after that until the user presses Enter: using Sys...

use std::fs::File; use std::io::Read; fn read_a_file() -> std::io::Result<Vec<u8>> { let mut file = try!(File::open("example.data")); let mut data = Vec::new(); try!(file.read_to_end(&mut data)); return Ok(data); } std::io::Result<T>...

public class MainApplication extends Application { private static Context context; //application context private Handler mainThreadHandler; private Toast toast; public Handler getMainThreadHandler() { if (mainThreadHandler == null) { mainThreadHand...

HTML comments (optionally preceded by whitespace) will cause code (on the same line) to be ignored by the browser also, though this is considered bad practice. One-line comments with the HTML comment opening sequence (<!--): Note: the JavaScript interpreter ignores the closing characters of H...

Arithmetic operations are performed elementwise on Numpy arrays. For arrays of identical shape, this means that the operation is executed between elements at corresponding indices. # Create two arrays of the same size a = np.arange(6).reshape(2, 3) b = np.ones(6).reshape(2, 3) a # array([0, 1...

If the file does not contain a header row, File: 1;str_data;12;1.4 3;str_data;22;42.33 4;str_data;2;3.44 2;str_data;43;43.34 7; str_data; 25; 23.32 you can use the keyword names to provide column names: df = pandas.read_csv('data_file.csv', sep=';', index_col=0, ski...

To create a human-readable presentation of a model object you need to implement Model.__str__() method (or Model.__unicode__() on python2). This method will be called whenever you call str() on a instance of your model (including, for instance, when the model is used in a template). Here's an exampl...

import java.io.*; import java.net.Socket; public class Main { public static void main(String[] args) throws IOException {//We don't handle Exceptions in this example //Open a socket to stackoverflow.com, port 80 Socket socket = new Socket("stackoverflow.com",8...

library(tidyr) ## example data set.seed(123) df <- data.frame( name = rep(c("firstName", "secondName"), each=4), numbers = rep(1:4, 2), value = rnorm(8) ) df # name numbers value # 1 firstName 1 -0.56047565 # 2 firstName 2 -0.2301...

Header fields (usually just called ‘headers’) may be added to an HTTP request to provide additional information with the request. A header has semantics similar to parameters passed to a method in any programming language that supports such things. A request with Host, User-Agent and Referer header...

When to use A read-only dependency property is similar to a normal dependency property, but it is structured to not allow having its value set from outside the control. This works well if you have a property that is purely informational for consumers, e.g. IsMouseOver or IsKeyboardFocusWithin. How...

On Debian-based distributions, including Ubuntu, the most straightforward way is to use the .deb installation file. Go to the Scala website. Choose the version you want to install then scroll down and look for scala-x.x.x.deb. You can install the scala deb from command line: sudo dpkg -i scala-x.x...

android { ... defaultConfig {...} buildTypes {...} productFlavors { demo { applicationId "com.example.myapp.demo" versionName "1.0-demo" } full { applicationId "com.example.myapp.full"...

<?php /** * Panel: WPCustomize * * Basic Customizer panel with basic controls. * * @since 1.0.0 * @package WPC */ // Exit if accessed directly. if ( ! defined( 'ABSPATH' ) ) { exit; } // Customize function. if ( ! function_exists( 'wpc_panel_wpcustomize' ) ) { ...

Panels can have sections, sections can have settings, and settings can have controls. Settings are saved in the database, while the controls for particular settings are only used to display their corresponding setting to the user. This code creates a basic section in the panel from above. Inside a...