Drupal’s Form API contains handy features for implementing Ajax that enhances the UX of your custom forms in a consistent and secure manner.
This course covers the basics of using the #ajax property in form elements, how to create dependent dropdowns that update based on user input, and how to submit forms via Ajax without requiring a page reload. You will also learn best practices for implementing Ajax in forms, including handling form validation and submission, and updating the form's display based on user interactions.
Key topics
- Introduction to using Ajax with forms in Drupal
- Creating dependent dropdowns with Ajax
- Submitting forms via Ajax
- Handling form validation and submission with Ajax
- Best practices for implementing Ajax in forms
- Using the
#ajaxproperty in form elements - Updating form display based on user interactions
Asynchronous JavaScript And XML (Ajax) is a programming practice for building more complex, dynamic webpages using a technology known as XMLHttpRequest. It allows you to asynchronously perform server-side operations without requiring a refresh, thus allowing for more complex user interaction and, in some cases, improved user experience.
In this tutorial we'll:
- Define what Ajax is
- Look at how Ajax is implemented in the Drupal Form API
- Provide links to additional resources to learn more about implementing Ajax in your own forms
By the end of this tutorial you should be able to explain what Ajax is, when you might want to use it, and how to get started doing so with Drupal's Form API.
A common use of Ajax is to alter a form by adding, removing, or updating parts of the form in response to actions taken by the user. The resulting altered form is still eventually submitted with a traditional HTTP POST request. For example, one might update the options available in a city dropdown field after someone has chosen a value in the country dropdown, or add an additional textfield for collecting a person's name when the user clicks an "Add another person" button.
In this tutorial we'll:
- Understand why certain types of modifications to a form require the use of Ajax
- Use
#ajaxin conjunction with a<select>field to demonstrate how to update a form with Ajax - Learn about responding to user interaction with
#ajax
By the end of this tutorial you should be able to use the #ajax attribute on any form element to respond to user actions and update the form displayed to the user with new content and options.
Using Ajax allows you to create forms that are submitted to the server, and processed, without requiring a page reload.
In this tutorial we'll:
- Use
#ajaxwith a'#type' => 'submit'button in order to submit a form via Ajax - Look at how form build, validation, and processing are used when submitting a form via Ajax
- Use the form's internal storage to track data across multiple requests
- Discuss some best practices to keep in mind when using Ajax for form submissions
By the end of this tutorial you should know how to update an existing form so that it is submitted via Ajax and no longer requires a page refresh to work.
