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PHP Object-Oriented PHP Basics Building a Collection Enhancing the Collection

Posted by jlampstack
jlampstack
23,932 Points

Alternative Render Solution???

I find it cleaner and easier to understand if we are to getRecipeTitles() in the Render display instead of when we call the Render.

public static function listRecipeTitles($collection)
    {
        $titles = $collection->getRecipeTitles();
        asort($titles);
        return implode("<BR>", $titles);
    }

This way when we call the Render we only need

echo Render::listRecipeTitles($cookbook);

Instead of 

echo Render::listRecipeTitles($cookbook->getRecipeTitles());

Is there a downside to doing it this way?

jamesjones21
jamesjones21
9,260 Points
jamesjones21
jamesjones21
9,260 Points

I think I share you verdict on this as it is easier to understand it your way when putting the method within the static method.

but I think Aleana is just stating what you can do, by naming the object and then passing it to the method.

Ben Payne
Ben Payne
1,464 Points

I'll throw in there that doing it your way would mean that $collection would always have to have the getRecipeTitles() method. So, an even better way would be to use an interface and rely on that. So that if a cookbook, or a stack of index cards, or some other collection were passed in you know they will implement that contract.

<?php

interface RecipeCollectionContract
{
    public function getRecipeTitles();
}

class Cookbook implements RecipeCollectionContract
{
    public function getRecipeTitles() // throws fatal if not implemented
    {
        // return titles
    }
}

class IndexCards implements RecipeCollectionContract
{
    public function getRecipeTitles() // throws fatal if not implemented
    {
        // return titles
    }
}

class Render
{
    public static function listRecipeTitles(RecipeCollectionContract $collection) // $collection must be an implementation of the contract
    {
        $titles = $collection->getRecipeTitles(); // Whatever is passed in adheres to the contract.
        asort($titles);
        return implode("<BR>", $titles);
    }
}
jlampstack
jlampstack
23,932 Points

Ben Payne , Excellent points. Thank you.

This is the reason I posted this question for insight that might be above my understanding. I haven't learned about contracts or implementing yet. I guess I will cross that bridge when I get there. If you're able to repost your thoughts as an answer, instead of a comment, I can mark it as best answer and we can close this topic.

Many Thanks!

Ben Payne
Ben Payne
1,464 Points

All set. Good on you for getting out of your comfort zone.

_Ben

1 Answer

Ben Payne
Ben Payne
1,464 Points
Ben Payne
Ben Payne
1,464 Points

Per the D (Dependency Inversion Principle) in SOLID it might be better use an interface (abstraction) and rely on that. So that if a cookbook, or a stack of index cards, or some other collection were passed in you know it will implement that contract.

<?php

interface RecipeCollectionContract
{
    public function getRecipeTitles();
}

class Cookbook implements RecipeCollectionContract
{
    public function getRecipeTitles() // throws fatal if not implemented
    {
        // return titles
    }
}

class IndexCards implements RecipeCollectionContract
{
    public function getRecipeTitles() // throws fatal if not implemented
    {
        // return titles
    }
}

class Render
{
    public static function listRecipeTitles(RecipeCollectionContract $collection) // $collection must be an implementation of the contract
    {
        $titles = $collection->getRecipeTitles(); // Whatever is passed in adheres to the contract.
        asort($titles);
        return implode("<BR>", $titles);
    }
}

Now the listRecipeTitles method has a dependency however its an abstraction. It doesn't know or care what is passed in just that it has the getRecipeTitles() method.