Custom form element "Linked checkbox"

This TYPO3 extension adds a custom form element "Linked checkbox" to the TYPO3 form framework. The user is able to define the link target and the link text.

Install

Copy the extension folder to \typo3conf\ext\ , upload it via extension manager or add it to your composer.json. Add the static TypoScript configuration to your TypoScript template.

Usage

Open the TYPO3 form editor and create a new form/open an existing one. Add a new element to your form. The modal will list the new custom form element "Linked checkbox". Provide a label for the checkbox and select a page you want to link to. Furthermore, you have to set a link text.

Combination of label and link

The default label consists of the label itself, followed by a link to the specified page with the given link text.

Example:

• Label: I accept the
• Link text: terms and conditions.
• Output: I accept the <a href="/privacy-policy" target="_blank">terms and conditions.</a>

If want to use the link inside your label, define the link position in the label with a character substitution.

Example:

• Label: I have read the %s and accept them.
• Link text: terms and conditions
• Output: I have read the <a href="/privacy-policy" target="_blank">terms and conditions</a> and accept them.

Link configuration

You can provide additional link configuration which will be used when generating the link within the label. Note that this can only be defined in the appropriate .form.yaml file but not in the Backend module.

type: LinkedCheckbox
identifier: privacy-policy
label: 'I accept the %s.'
properties:
  pageUid: '67'
  linkText: 'terms and conditions'

renderingOptions:
  linkConfiguration:
    # Additional typolink configuration can be inserted here, e.g.:
    no_cache: 1

For a full list of available configuration take a look at the TypoScript reference.

Override default link target

By default, the link target is set to _blank. If you want to override it, just define a custom link configuration parameter – either an empty string or a custom target/additional parameter configuration:

renderingOptions:
  linkConfiguration:
    parameter: ''

Possible improvements or changes

Instead of creating a new form element, the existing Checkbox form element could have been extended. In order to provide a more complex example, the extension creates a new element.

At the time of writing this, you have to provide a small JavaScript snippet (see \Resources\Public\JavaScript\Backend\FormEditor\ViewModel.js). This snippet is needed to show the custom form element in the form editor. For TYPO3 v9 we are aiming to remove this stumbling block to smoothen the element registration.

Credits

This exemplary TYPO3 extension was created by Björn Jacob (https://www.tritum.de). The idea was born at the TYPO3 CertiFUNcation Day 2017. The audience of my talk kindly asked for such an element. Lightheaded, I said it will not take more than 30 minutes to create such an extension. Unfortunately, I could not make it in this time. It took my nearly 1.5 hours to come up with all the code. The JS part gave me a hard time.

Thank you

Jochen Weiland - TYPOholic at https://jweiland.net - supported this challenge in multiple ways. Thanks for being an outstanding part of our TYPO3 community.