Using TypoScript For Rendering: The cObject-ViewHelper

The cObject-ViewHelper is a very powerful ViewHelper. It connects Fluid with the options that TypoScript offers. The following line in the HTML template will be replaced with the referenced TypoScript object.

<f:cObject typoscriptObjectPath="lib.title"/>

Now we only have to define lib.title in the TypoScript Setup:

lib.title = TEXT
lib.title.value = Extbase and Fluid

»Extbase and Fluid« will be outputted in the template. Now we can output an image (e.g. headlines with unusual fonts) by changing the TypoScript to:

lib.title = IMAGE
lib.title {
   file = GIFBUILDER
   file {
      10 = TEXT
      10.value = Extbase and Fluid
   }
}

So far it's not really a "real world" example, because no data is being passed from Fluid to the TypoScript. We'll demonstrate now how to pass a parameter to the TypoScript with the example of a user counter. The value of our user counter should come from the Blog-Post. (Every Blog-Post should count how many times it's been viewed in this example).

In the Fluid template we add:

<f:cObject typoscriptObjectPath="lib.myCounter">{post.viewCount}</f:cObject>

Alternatively we can use a self closing tag. The data is being passed with the help of the data attribute.

<f:cObject typoscriptObjectPath="lib.myCounter" data="{post.viewCount}" />

Also advisable for this example is the inline notation, because you can easily read it from left to right:

{post.viewCount -> f:cObject(typoscriptObjectPath: 'lib.myCounter')}

Now we still have to evaluate the passed value in our TypoScript template. We can use the stdWrap attribute current to achieve this. It works like a switch: If set to 1, the value, which we passed to the TypoScript object in the Fluid template, will be used. In our example it looks like this:

lib.myCounter = TEXT
lib.myCounter {
   current = 1
   wrap = <strong>|</strong>
}

This TypoScript snippet outputs the current number of visits written in bold.

Now for example we can output the user counter as image instead of text without modifying the Fluid template. We simply have to use the following TypoScript:

lib.myCounter = IMAGE
lib.myCounter {
   file = GIFBUILDER
   file {
      10 = TEXT
      10.text.current = 1
   }
}

At the moment we're only passing a single value to the TypoScript. It's more versatile though to pass multiple values to the TypoScript object, because then you can select which value to use in the TypoScript and the values can be concatenated. You can also pass whole objects to the ViewHelper in the template:

{post -> f:cObject(typoscriptObjectPath: 'lib.myCounter')}

Now, how do you access individual properties of the object in the TypoScript-Setup? You can use the property field of stdWrap:

lib.myCounter = COA
lib.myCounter {
   10 = TEXT
   10.field = title
   20 = TEXT
   20.field = viewCount
   wrap = (<strong>|</strong>)
}

Now we always output the title of the blog, followed by the amount of page visits in parenthesis in the example above.

You can also combine the field based approach with current: If you set the property currentValueKey in the cObject ViewHelper, then this value will be available in the TypoScript template with current. This is especially useful when you want to emphasize that the value is very important for the TypoScript template. For example, the amount of visits is very important in our view counter:

{post -> f:cObject(typoscriptObjectPath: 'lib.myCounter', currentValueKey: 'viewCount')}

In the TypoScript template you can now use both, current and field, and have therefor the maximum flexibility with the greatest readability. The following TypoScript snippet outputs the same information as the previous example:

lib.myCounter = COA
lib.myCounter {
   10 = TEXT
   10.field = title
   20 = TEXT
   20.current = 1
   wrap = (<strong>|</strong>)
}

The cObject ViewHelper is a powerful option to use the best advantages of both worlds by making it possible to embed TypoScript expressions in Fluid templates

In the next chapter, we'll turn our attention to a function which most ViewHelper have. This function makes it possible to modify the HTML output of a ViewHelper by adding your own tag attributes.