TooBasic: Using Snippets

Snippets?

You may already know this, but if you don't a snippet is "a small region of re-usable source code".

In other words, it's a piece of code you write in many of your actions and you want to write it once and invoke it from your actions, instead of writing it every time, which is a pain in the... a headache to maintain.

For example, if some of your actions show a section to jump between pages (let's call it pager), you may create a nice piece of HTML and paste every time you need it. Well. that is a snippet and our examples will be based on that idea.

For our examples we're are going to create a snippet called pager to show page buttons inside an action with pagination.

Let's create a file with this content:

{if $show}
<div class="Pager">
  <a href="?{$first.query}" title="{$first.id}"><span title="First" class="glyphicon glyphicon-fast-backward"></span></a>
  <a href="?{$previous.query}" title="{$previous.id}"><span title="Previous" class="glyphicon glyphicon-backward"></span></a>

  {foreach from=$pages item=page}
  {if $page.current}
  <a class="Current" href="#" title="{$page.id}" onclick="return false;">{$page.id}</a>
  {else}
  <a href="?{$page.query}" title="{$page.id}">{$page.id}</a>
  {/if}
  {/foreach}

  <a href="?{$next.query}" title="{$next.id}"><span title="Next" class="glyphicon glyphicon-forward"></span></a>
  <a href="?{$last.query}" title="{$last.id}"><span title="Last" class="glyphicon glyphicon-fast-forward"></span></a>
</div>
{/if}

And save it in ROOTDIR/site/snippets/pager.html.

Note: This snippet uses some Bootstrap notations.

To make things a little more interesting, let's create a model to manage this new snippet. Something like the next code and store it in ROOTDIR/site/models/Pager.php:

<?php
class PagerModel extends \TooBasic\Model {
    const SURROUNDING_LENGTH = 10;
    public function snippetSets($maxPage, $currentPage) {
        $out = ["show" => true];
        if($maxPage > 1) {
            $pattern = "/^((.*)&|)page=([0-9]*)(.*)$/";
            $currentPage = $currentPage > $maxPage ? $maxPage : $currentPage;
            $query = $_SERVER["QUERY_STRING"];
            if(!$query) {
                $query = "page=1";
            } else {
                if(!preg_match($pattern, $query)) {
                    $query.="&page=1";
                }
            }
            $pages = [];
            for($i = 1; $i <= $maxPage; $i++) {
                $pages[$i] = [
                    "current" => $currentPage == $i,
                    "id" => $i,
                    "query" => preg_replace($pattern, "\$2&page={$i}\$4", $query)
                ];
            }
            $out["first"] = $pages[1];
            $out["last"] = $pages[$maxPage];
            $out["previous"] = $pages[$currentPage == 1 ? 1 : $currentPage - 1];
            $out["next"] = $pages[$currentPage == $maxPage ? $maxPage : $currentPage + 1];
            $minIndex = $currentPage - self::SURROUNDING_LENGTH;
            $minIndex = $minIndex > ($maxPage - (self::SURROUNDING_LENGTH * 2) ) ? ($maxPage - (self::SURROUNDING_LENGTH * 2) ) : $minIndex;
            $minIndex = $minIndex < 1 ? 1 : $minIndex;
            $out["pages"] = array_slice($pages, $minIndex - 1, (self::SURROUNDING_LENGTH * 2) + 1, true);
        } else {
            $out["show"] = false;
        }
        return $out;
    }
    protected function init() {}
}

Why a model? Well this will help you avoid some settings and make your code simpler.

Current problem

Let's suppose your are working with an action that lists a long list of thing and you ended up with something like this:

Controller ROOTDIR/site/controllers/things.php:

<?php
class ThingsController extends \TooBasic\Controller {
  protected function basicRun() {
      $out = true;
      $thingsToShow = $this->model->stuff->things();
      $this->assign("things", $thingsToShow);
      return $out;
  }
}

Template ROOTDIR/site/templates/action/things.html:

<div class="Things">
  {foreach from=$things item=thing}
  <div class="Thing">
      <span class="Id">{$thing.id}</span>
      <span class="Name">{$thing.name}</span>
  </div>
  {/foreach}
</div>

Of course you want to add a pagination system.

... and yes, we've assumed your are using smarty.

Note here

The model stuff doesn't really exist, it's just and example... duh :)

Adding pages

Let's add some code using our snippet:

Modify your controller into something like this:

class ThingsController extends \TooBasic\Controller {
  const MAX_PER_PAGE = 100;
  protected function basicRun() {
      $out = true;
      $thingsToShow = $this->model->stuff->things();
      $currentPage = isset($this->params->get->page) ? $this->params->get->page : 1;
      $currentPage = $currentPage > 0 ? $currentPage : 1;
      $totalCount = count($thingsToShow);
      $thingsToShow = array_slice($thingsToShow, ($currentPage - 1) * self::MAX_PER_PAGE, self::MAX_PER_PAGE, true);
      $this->setSnippetDataSet("pagerdata", $this->model->pager->snippetSets(ceil($totalCount / self::MAX_PER_PAGE), $currentPage));
      $this->assign("things", $thingsToShow);
      return $out;
  }
}

And your template into this:

<div class="Things">
  {foreach from=$things item=thing}
  <div class="Thing">
      <span class="Id">{$thing.id}</span>
      <span class="Name">{$thing.name}</span>
  </div>
  {/foreach}
</div>
{$ctrl->snippet("pager","pagerdata")}

All done! Now your controller sends just a chunk of all the things it has to its template and also sets the information for the snippet pager.

Explain it!

The example may be a little vague, so let's explain a few things.

How to invoke a snippet.

The simplest way to invoke a snippet is using a code like this:

{$ctrl->snippet("snippetname")}

This will load a piece of code stored in ROOTDIR/site/snippets/snippetname.html and insert it inside your template when it's rendered. If the snippet uses variables, these will be taken from the assignments made by your controller.

Separated assignments

Because a snippet is a piece of code you may want to insert it more than once in the same template, and there you'll probably get some troubles when trying to obtain different results on each insertion. Well, there is a way to point a different set of assignments on each invocation:

{$ctrl->snippet("snippetname","set1")}
{$ctrl->snippet("snippetname","set2")}
{$ctrl->snippet("snippetname","set3")}

By default this will have no effect unless some changes are made in the controller. Here's when you need to use the method setSnippetDataSet() in your controller:

class ExampleController extends \TooBasic\Controller {
    protected function basicRun() {
        $this->setSnippetDataSet("set1", ["key"=>"A","value"=>1]);
        $this->setSnippetDataSet("set2", ["key"=>"B","value"=>2]);
        $this->setSnippetDataSet("set3", ["key"=>"C","value"=>3]);
        return true;
    }
}

This will cause your snippet to act in a different way on each invocation. And yes, this is the technique used in our example.

Something good

Using the method setSnippetDataSet() will help you keep your controller and template clean because non of its assignments are exported towards you template, their are used only inside the appropriate snippets.

Suggestions

If you want or need, you may visit these documentation pages:

Using Snippets

TooBasic: Using Snippets

Snippets?

Current problem

Note here

Adding pages

Explain it!

How to invoke a snippet.

Separated assignments

Something good

Suggestions

results matching ""

No results matching ""

TooBasic: Using Snippets

Snippets?

Pager snippet

Pager snippet mananger

Current problem

Note here

Adding pages

Explain it!

How to invoke a snippet.

Separated assignments

Something good

Suggestions

results matching ""

No results matching ""