Collections

Overview Objective Learn how add and retrieve information into a collection. Requirements Basics of ProdigyView Estimated Time 8 minutes www.prodigyview.com

Follow Along With Code Example Download a copy of the example code at www.prodigyview.com/source. Install the system in an environment you feel comfortable testing in. Proceed to examples/design/Collections.php

What Are Collections In programming a collection resembles a container. A container can be described as a class or data structure that is composed of instances of other objects and/or variables. In other words, it’s a class designed for holding data of a specific type or any type. Some collections may hold only strings while other collections may hold strings, doubles, and integers. In ProdigyView, collections store any type of data and can be ran through an iterator when needed. www.prodigyview.com

Collections Visual My Collections Box My collections can hold anything!

Creating A Collection Let’s start out by simply creating a collection and adding some data too it. Using the add() function will add a value to the collection. Instantiate the collections object Add Values to the Collection

Adding Name Data That was very straight forward. Now we are going to add more information in, except this time we are going to define a key so we easily find the data later. Set the key that will be used to access the collection Set the value to be stored in the collection associated with the key

Recalling Information If you haven’t caught on yet, we’ve been adding a famous 1970 pop single. Now in our last slide we added data with a key. Let’s get that data back using the key. Retrieve the value stored in the collection based on the key

Recalled Info www.prodigyview.com

The Iterator So we’ve added all this data to the collection and we can pull it out using the name/key if we know it. What about data that was added without a key using the add method? At this point we need to iterate through our data using the built in iterator. Get the collection’s iterator Iterate through the collection

The Iterator Says… Looping through the iterator should give you this:

Iterate Manually Now on some occasions we might want to have control of the iterator. Not a problem, lets move it up, down, left and right as we please.

Iterate Manually Results The output from iterating manually. www.prodigyview.com

The Not So Obvious PVCollections can take any object, array, or singular value and add it the collection. The iterator is actually a class called PVIterator which can be called to work on its own when needed. Every object that extends PVObject and PVStaticObject has a PVCollection. Using the magic functions __set() and __get() will put and retrieve information into that collection. www.prodigyview.com

Summary Using the add() function to added an item to the collection. Use the addWithName() to add an item by it’s name. Item can be retrieved by it’s name also. Use the getIterator() to retrieve the iterator and iterate through the data in the collection. www.prodigyview.com

API Reference For a better understanding of the Collections and the Iterator, check out the api at the two links below. PVCollections PVIterator www.prodigyview.com More Tutorials For more tutorials, please visit: http://www.prodigyview.com/tutorials