c# barcode generator wpf ACTION PACK: WORKING WITH THE VIEW AND THE CONTROLLER in Font

Generation PDF-417 2d barcode in Font ACTION PACK: WORKING WITH THE VIEW AND THE CONTROLLER

ACTION PACK: WORKING WITH THE VIEW AND THE CONTROLLER
Draw PDF 417 In None
Using Barcode encoder for Font Control to generate, create PDF-417 2d barcode image in Font applications.
www.OnBarcode.com
GTIN - 13 Maker In None
Using Barcode creator for Font Control to generate, create EAN-13 Supplement 5 image in Font applications.
www.OnBarcode.com
Each controller in Rails is designed as a Ruby class. Without getting too technical, Listing 6-1 shows how the CD player example would look if it were a Ruby class. Listing 6-1. CDPlayer Class class CDPlayer def play end def stop end def fast_forward end def rewind end def eject end end Inside the CDPlayer class, you define a method for each action, or each thing you want your CD player to be able to do. So, if you were to send the message play to an instance of the CDPlayer class, it would know how to handle it (of course, because the play method is empty in this example, nothing would happen). On the other hand, if you sent the message pause, Ruby would raise an exception and tell you that the method wasn t found. If you wanted CDPlayer objects to respond to that message, you would need to add a method called (you guessed it) pause. All the methods in this class are public, which means they can be invoked by anyone. You don t need to do anything special to a method to make it public. Unless otherwise declared, all methods in a Ruby class are public by default. If you were to mark an action as private, though, it could be used only internally by the class. For example, if the stop method were private, it would raise a NoMethodError if you called it from outside the CDPlayer class. However, the eject method is free to call on stop, because it does so internally. Although the usefulness of this feature will become apparent as you continue to learn about controllers, consider this: if your CD player needed to display the time remaining for a given track, it might need to perform a few calculations to figure that out. You might create a method for doing these internal calculations, but would you want that method to be accessible from the outside Would you have a button called Calculate on your player It s time for a working definition: Action Controllers are Ruby classes containing one or more public methods known as actions. Each action is responsible for responding to a request to perform some task. A typical controller is most often a collection of actions that relate to a specific area of concern. For example, consider the blog application you ve been building in the previous chapters. The controller that manages articles has the class name ArticlesController and has action methods for listing, creating, reading, updating, and deleting articles. The example of the CD player worked well to illustrate the basic concept of controllers, it won t take you much further when dealing with web applications. If you were really dealing with a CD player, you would press Play, the disc would start playing, and that would be the end of it. But because Rails was specifically designed for building web applications, it makes a fair number of assumptions about what you want your actions to do when they re finished firing. Chief among these is the rendering of a view. Imagine that you re reading a list of posts on someone s blog. You click the title of a post, and you expect to be taken to a new screen that shows you just that post. You requested an action (show), and in
Generating USS-128 In None
Using Barcode creator for Font Control to generate, create UCC.EAN - 128 image in Font applications.
www.OnBarcode.com
QR-Code Creator In None
Using Barcode printer for Font Control to generate, create QR Code 2d barcode image in Font applications.
www.OnBarcode.com
ACTION PACK: WORKING WITH THE VIEW AND THE CONTROLLER
ECC200 Encoder In None
Using Barcode printer for Font Control to generate, create ECC200 image in Font applications.
www.OnBarcode.com
Create Code-39 In None
Using Barcode drawer for Font Control to generate, create Code 39 Extended image in Font applications.
www.OnBarcode.com
response, you receive a new screen. This happens all the time in the world of web applications: when you click a link, you expect to go to a new page. In Rails, it s the general case that when actions have completed their work, they respond by rendering a view. The concept of actions rendering views is so common that Rails has internalized it as a convention: unless otherwise stated, when an action is finished firing, it renders a view. How does Rails know what view to render if you don t tell it It looks for a view whose name matches that of the requested action. This should give you some insight as to why Action Controller and Action View are bundled together in Action Pack. Because of the way controller actions relate to views, a few other mechanisms facilitate their communication, all of which are covered shortly.
ANSI/AIM Code 128 Drawer In None
Using Barcode creation for Font Control to generate, create Code 128B image in Font applications.
www.OnBarcode.com
ISSN Drawer In None
Using Barcode creator for Font Control to generate, create International Standard Serial Number image in Font applications.
www.OnBarcode.com
Making PDF 417 In Visual C#
Using Barcode generation for .NET Control to generate, create PDF 417 image in VS .NET applications.
www.OnBarcode.com
PDF417 Maker In None
Using Barcode drawer for Online Control to generate, create PDF417 image in Online applications.
www.OnBarcode.com
Barcode Recognizer In Java
Using Barcode Control SDK for Eclipse BIRT Control to generate, create, read, scan barcode image in BIRT reports applications.
www.OnBarcode.com
Printing Code 128 Code Set A In Java
Using Barcode drawer for Java Control to generate, create ANSI/AIM Code 128 image in Java applications.
www.OnBarcode.com
Generate GS1 DataBar Truncated In .NET Framework
Using Barcode generator for .NET Control to generate, create GS1 DataBar Stacked image in .NET framework applications.
www.OnBarcode.com
Barcode Maker In None
Using Barcode drawer for Office Word Control to generate, create Barcode image in Office Word applications.
www.OnBarcode.com
QR Code Reader In None
Using Barcode decoder for Software Control to read, scan read, scan image in Software applications.
www.OnBarcode.com
UCC.EAN - 128 Maker In None
Using Barcode generator for Online Control to generate, create UCC.EAN - 128 image in Online applications.
www.OnBarcode.com
1D Encoder In VS .NET
Using Barcode generation for .NET framework Control to generate, create Linear Barcode image in VS .NET applications.
www.OnBarcode.com
QR Creation In Objective-C
Using Barcode generator for iPad Control to generate, create QR image in iPad applications.
www.OnBarcode.com
Code-39 Reader In C#
Using Barcode reader for Visual Studio .NET Control to read, scan read, scan image in VS .NET applications.
www.OnBarcode.com
DataMatrix Creation In Java
Using Barcode drawer for Android Control to generate, create Data Matrix ECC200 image in Android applications.
www.OnBarcode.com
Copyright © OnBarcode.com . All rights reserved.