CURRENT WINDOW
Makes a specified window the current window.
Syntax
CURRENT WINDOW IS {
identifier |
SCREEN }
- identifier is the name of the window.
Usage
Programs with multiple windows might need to switch to a different
open window so that input and output occur in the appropriate window. To make a window the
current window, use the CURRENT WINDOW
statement.
When a program starts, the screen is the current window. Its name is SCREEN
.
To make this the current window, specify the keyword SCREEN
instead of a window
identifier.
If
the window contains a form, that form becomes the current form when a CURRENT
WINDOW
statement specifies the name of that window. All interactive instruction
such as CONSTRUCT
, INPUT
use only the current window for
input and output. If the user displays another form (for example, through an ON
KEY
clause) in one of these statements, the window containing the new form
becomes the current window. When an interactive instruction resumes, its original window
becomes the current window.
The CURRENT WINDOW
instruction is typically used in text user interface (TUI)
based applications, when distinct areas of the screen are reserved for different usage. In a GUI
application, windows are typically opened and closed sequentially or on a stack of windows.
Example
MAIN
OPEN WINDOW w1 WITH FORM "customer"
...
OPEN WINDOW w2 WITH FORM "custlist"
...
CURRENT WINDOW IS w1
...
CURRENT WINDOW IS w2
...
CLOSE WINDOW w1
CLOSE WINDOW w2
END MAIN