Chapter 12, Problem 7AW

Explanation of Solution

ID selectors:

• In the graph each node can optionally assigned with a unique identifier that is called as ID.
• A node’s ID is a string that can be used to determine the node in a style sheet.
  • It is also used to permit the user to apply a style to one particular node.
• Using the node’s “setId()” method, user can assign an ID to a node.

Example:

The example for assigning an ID to a node:

button1.setId("button-error");

The above code is used to assign an ID to a “Button” control.

• The “button1” represents a Button control...