Using Vision Advanced Features
This chapter describes the advanced functions that Vision provides. When you develop Vision applications, you can use these functions to:
• Specify more complex queries
• Make your applications easier to use
• Make your applications more efficient
Vision advanced features include:
• Parameters to pass values between frames
• Local variables to define hidden fields for a frame
• Local procedures to define 4GL procedures for a frame
• Global components—constants and variables to set values throughout an entire application, or record types to define your own data types
• Escape code that you write to perform additional functions at specific points when you run a frame
To write escape code, you need to be familiar with 4GL. The 4GL part of this guide provides a comprehensive guide to the 4GL statements and their syntax.
Note: This chapter contains a separate section describing how to use each of the advanced features. However, you can use several of these features together; for example, by writing escape code to tell Vision how to use a local variable. To combine advanced features, refer to the specific sections of this chapter that describe those functions.