The Dialog Control is designed to allow you to retrieve information from the user and make use of that information within the page — whether interally to the page or by sending the information to the server via form post or XMLHttpRequest. This example shows how to do the latter. Click the button to show the Dialog instance and its form fields; fill out the form; submit the form. Dialog will automatically use the YUI Connection Manager to send the data via XMLHttpRequest to the server and will then echo that data back to you on the page.
The Dialog component is an extension of Panel that is meant to emulate the behavior of an dialog window using a floating, draggable HTML element. Dialog provides an interface for easily gathering information from the user without leaving the underlying page context. The information gathered is collected via a standard HTML form; Dialog supports the submission of form data through XMLHttpRequest, through a normal form submission, or through a manual script-based response (where the script reads and responds to the form values and the form is never actually submitted to the server).
Instantiating a Dialog is very similar to other controls in the Container collection. In this tutorial, we will create a Dialog from existing markup where the container element's id is "dialog1":
The properties for width, fixedcenter, visible, and constraintoviewport are inherited from Panel. Unique to the Dialog control is the buttons property, which takes an array of object literals representing the buttons that will be rendered in the Dialog's footer. Each one of these button literals has three possible properties: "text" which represents the button text, "handler" which is a reference to the function that will execute when the button is clicked, and "isDefault" which will apply a bold style to the button when set to true.
Next, we must define the handleCancel and handleSubmit handlers for our buttons. In this tutorial, the submit and cancel buttons will call the corresponding functions in the Dialog:
By default, the Dialog is submitted using the Connection Manager. In order to handle the response from the server, we must define callback functions that will execute when the submission has occurred. First, we will define the functions, and then we will set them into our Dialog's callback — the same callback object that will be passed to Connection Manager's asyncRequest method. For the purposes of this example, the success handler will simply diplay the server response on the page. The failure handler will alert the response status code, if something goes wrong:
Note: Logging and debugging is currently turned off for this example.
All YUI 2.x users should review the YUI 2.8.2 security bulletin, which discusses a vulnerability present in YUI 2.4.0-2.8.1.