SilverStripe arithmetic in template - silverstripe

I want to do a simple arithmetic operation in a .ss template.
<% loop $Images %>
<img src="$Link" alt=""/>
<% $Pos == 4 %>
and {$TotalItems - 4} more foto's
$Break
<% end_if %>
<% end_loop %>
For example I would want to output
and 10 more foto's
But the best I can get is
and 14 - 4 more foto's
I know I can make a function, which works for now, but can I do arithmetic operations in the template?

You could do it like this.
At first you limit the images to the amount you would like to display. After that you loop over the same set with an offset of x (4) and check if there's more. If so, output the amount of remaining images.
<% loop $Images.Limit(4,0) %>
<img src="$Link" alt=""/>
<% end_loop %>
<% if $Images.Limit(9999,4) %>
and $Images.Limit(9999,4).Count more foto's
<% end_if %>
the code is untested but should work.
Edit
I think "real" arithmetic is not possible by default. You'll need to write a custom function to do this.

Related

Silverstripe: Template behavior of "Up"

In Silverstripe templating, the $Up tag temporarily breaks out of the current loop/with and gives access to the parent scope. While the following template code works, I don't understand why.
$Checked is a list with objects that I loop, in itself containing a list with $Items of which I need to show the first. The object also has an Owner, which I need to access while in the scope of the first item.
I've got the following silverstripe template code:
<% loop $Checked %>
<% with $Items.First %>
<article class="checked-statement">
<span class="statement-outcome h-bg-true-$Verdict.Value">$Verdict.Name</span>
<div class="checked-statement__statement">
<a href="xxx" class="checked-statement__picture"><img
src="$Up.Up.Owner.Photo.CroppedImage(160,160).Url" alt="$Up.Up.Owner.Name.XML" class="h-full-rounded"/></a>
$Up.Up.Owner.Name zei
<h3>
$Up.Up.Title
</h3>
</div>
<a href="yyy" class="checked-statement__argument">
$Up.Up.Statement…
$Top.Icon('chevron-right')
</a>
</article>
<% end_with %>
<% end_loop %>
I would think I would need only one "Up" to get to the scope of $Checked. But I need two, which is strange, as the first Up should break out of the "with", and the second one should break out of the loop, giving me the top level scope, in which the specific item is not available...
Can anyone point me at the fault in my reasoning, or code?
At some point, I believe it was with 3.0 or 3.1, the logic behind $Up changed.
Previously <% with $Items.First %> or back in 2.x <% control $Items.First %> was just one scope level that you could break out of with $Up.
These days, each object/method call/property gets it's own scope. This means:
<% with $Foo.Bar %>Foo's ID: $Up.ID<% end_with %>
<% with $Foo.Bar %>Outside of "with" ID: $Up.Up.ID (== $Top.ID in this case)<% end_with %>
And for deeper nesting you need even more ups:
<% with $Foo.Bar.X %><% loop $Y %>$Up.Up.Up.Up.ID == $Top.ID<% end_loop %><% end_with %>

SilverStripe GroupedList with has_one data

I'm banging my head trying to figure this out and I feel like I'm over thinking it.
So I've built 2 DataObjects (Brand, Product) and 1 Controller/Page (ProductType).
ProductType has many Products
Product has one Brand
Product has one ProductType
Brand has many Products
What I'm looking to do is:
ProductType pages should make available a list of Brands that are used ONLY by the Products of that Type.
Now I have one somewhat working but it feels hacky and not very portable. Example below:
ProductType Controller:
public function getBrands() {
if($products = $this->Products()) {
$group = GroupedList::create($products->sort('BrandID'))->GroupedBy('BrandID');
}
}
Product Type Template:
<% if Brands %>
<ul>
<li>All</li>
<% loop Brands %>
<% loop Children.Limit(1) %>
<li>$Brand.Title</li>
<% end_loop %>
<% end_loop %>
</ul>
<% end_if %>
Is there a way I can build a method in the ProductType controller that would return a DataList of just the Brands used by Products of that type?
Using Silverstripe 3.1.3
Let me know if I need to be more clear about something and thanks!
Ah, i guess you had a misunderstanding of a GroupedList
You already have the Datalist of all products of this product type.
It's the has_many relation
$this->Products()
now you want to group the current products by BrandID. Your method naming might be confusing, so let's rename it a bit:
public function getProductsGroupedByBrands() {
if($products = $this->Products()) {
$group = GroupedList::create($products->sort('BrandID'))
->GroupedBy('BrandID');
}
}
So in your template you have a GroupedList you can loop over.
<% if Products %>
<ul>
<li>All</li>
<% loop ProductsGroupedByBrands %>
<li>
<%-- here you should be able to see the grouping relation --%>
$Brand.Title
<%-- in doubt use the First element to get the current Brand, it's a has_one -->
<% with $Children.First %>
$Brand.Title
<% end_with %>
<ul>
<% loop Children %>
<%-- here are the products grouped by brand --%>
<li>$Title</li>
<% end_loop %>
</ul>
</li>
<% end_loop %>
</ul>
<% end_if %>
See also Silverstripe Docs or Grouping Lists

Using article frontmatter when iterating in Middleman blog

Not the best title, but I'm honestly not sure on how to properly explain what I'm looking for help for.
So I'm using Middleman blog to well create my blog. Anyways, I'm using frontmatter to pass css that change the look of each page individually. I'm using 4 variables, link_color, text_color, bg_link. So what I want to do is reuse that same frontmatter information in the layout.html.erb file.
So the layout.html.erb is the standard
<% if paginate && num_pages > 1 %>
<p>Page <%= page_number %> of <%= num_pages %></p>
<% if prev_page %>
<p><%= link_to 'Previous page', prev_page %></p>
<% end %>
<% end %>
<% page_articles.each_with_index do |article, i| %>
<li class="article_summary">
<h1><%= link_to article.title, article, id: "#{i}" %></h1>
</li>
<% end %>
<% if paginate %>
<% if next_page %>
<p><%= link_to 'Next page', next_page %></p>
<% end %>
<% end %>
What I'm trying to do is for each article within that iterator is if the article has bg_color frontmatter then use that and change the color of the article.title if not, then do nothing. Currently if I try with something like:
<style>
<% if article.data.bg_color? %>
.article_summary a#<%= i %>{
color: rgb(<%=article.data.bg_color %>);
}
<% end %>
</style>
I'm doing it this way because my blog lives on Github.
Currently it works, but since it's just a simple iteration it gives every article that same color and not on a per article basis. So I'm trying to figure out the best way to utilize the index as some sort of id so that they're targeted individually.
Perhaps changing the li from a class to an id consisting of the index, but then I won't be able to apply a global style from the scss in the stylesheet folder no?
I've found a dirty method that works.
<% page_articles.each_with_index do |article, i| %>
<li class="article_summary" id="test_<%=i %>">
<h1><%= link_to article.title, article %></h1>
<style>
<% if article.data.bg_color? %>
#test_<%=i%> a{
color: <%=article.data.bg_color %>;
}
<% end %>
</style>
</li>
<% end %>
Pretty much added "test_" to the id (before I was just doing the index itself) and viola!

Creating article pagination

Hi I'm using silverstripe 2.4.7 and I'm having difficulty getting the pagination to work. I've created a function in my page.php to get the latest articles like so
function AllNewsPosts($num=1) {
$news = DataObject::get_one("NewsHolder");
return ($news) ? DataObject::get("NewsEntry", "ParentID > 0", "Date DESC", "", $num) : false;
}
Then when i put this function into the control and pagination tags one article shows up however the links to the concurrent articles do not work - essentially the pagination is not working and I'm not sure how to fix it
<% if AllNewsPosts %>
<% control AllNewsPosts %>
<div class="event">
<h2>$MenuTitle |<span class="date"> $Date.Time $Date.Long</span></h2>
<p>$Content.FirstParagraph</p>
See more about this event
</div>
<% end_control %>
<% else %>
<div class="no-entry">'There are no entries'</div>
<% end_if %>
<% if AllNewsPosts.MoreThanOnePage %>
<div id="PageNumbers">
<p>
<% if AllNewsPosts.NotFirstPage %>
<a class="prev" href="$AllNewsPosts.PrevLink" title="View the previous page"><span class="yellow-background">Prev</span></a>
<% end_if %>
<span>
<% control AllNewsPosts.PaginationSummary(0) %>
<% if CurrentBool %>
<span class="current">$PageNum</span>
<% else %>
<% if Link %>
$PageNum
<% else %>
…
<% end_if %>
<% end_if %>
<% end_control %>
</span>
<% if AllNewsPosts.NotLastPage %>
<a class="next" href="$AllNewsPosts.NextLink" title="View the next page"><span class="yellow-background">Next</span></a>
<% end_if %>
</p>
</div>
<% end_if %>
Any help is much appreciated
Note: The following answer is for Silverstripe 2.4. This should not be used for Silverstripe 3.0+ sites. From 3.0 and onwards the PaginatedList object makes pagination much easier.
You are not setting a limit on how many entries to retrieve in your query, or where to start from.
The following tutorial explains how to apply pagination to a set of data objects exactly as you are trying to do:
http://www.ssbits.com/tutorials/2010/paginating-a-filtered-dataobjectset/
Here is an attempt at altering your function to include limit and start as needed for pagination:
PHP
function AllNewsPosts() {
if(!isset($_GET['start']) || !is_numeric($_GET['start']) || (int)$_GET['start'] < 1)
{
$_GET['start'] = 0;
}
$SQL_start = (int)$_GET['start'];
$newsEntries = DataObject::get('NewsEntry', '', 'Date DESC');
$doSet = new DataObjectSet();
foreach ($newsEntries as $newsEntry) {
if ($newsEntry->canView()) {
$doSet->push($newsEntry);
}
}
$doSet->setPageLimits($SQL_start, 10, $doSet->Count());
return $doSet;
}
Note the above will display 10 items per page. You can change this to however you need per page.

What is the difference between <% %> and <%= %>?

I tried to find the difference on Google.
BUT
I 'm not able to search with '<% %>' , maybe the reason is <% is a HTML TAG
Now i'm thinking there's no diffrence betwwen <% and <%= .
<% %> executes the code between the 2 brackets.
<%= %> returns the value between the 2 brackets.
Example:
<% Response.Write("Hello.") %>
vs
<%= "Hello" %>
<% %> and <%= %> are normally server side scripts, the difference is first one does not print out the value to the page, unless you explicitly use print function, but second one will do automatically
Are you talking about the ASP ? If yes then <% %> is to hold the server side code and this is <%= %> equivalent to the Response.Write().
They're generally referred to as beestings. These particular ones are used by ASP.Net or ASP Classic. <% %> signifies server side code and <%=<Something%> is shorthand for <% Response.Write(<Something>) %>
If you want to show current date in a page you can do either of the following to write the date to the document. In the first sample using <% %> you have to explicitly use Response.Write.
<% Response.Write(DateTime.Now.ToString()) %>
and in the following one no need to explicitly write Response.Write
<%= DateTime.Now.ToString() %>

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