Progress
Programming
Handbook
Key Monitoring
Often, an application does not need to be aware of specific keystrokes or mouse actions by the user because the normal functionality provided by Progress and the window system is sufficient. This is frequently true when you use the procedure-driven programming model. However, you might want to define a special behavior to occur when the user presses a specific key or mouse button. For example, every time the user presses a certain key, you might want to display a message or take some action. This is called monitoring the user’s keystrokes. Progress provides a set of language constructs to do this, including user interface triggers. For more information, see the "Monitoring Keystrokes During Data Entry" section.
During a session, Progress responds to key code events according to a precedence that depends on the current user interface and the application design. Table 6–1 shows the general order of precedence for Progress key code events.
Thus, when the user presses a key, Progress first checks to see if it corresponds to an active accelerator in the current window. If not, Progress checks for a user interface trigger for that key, then whether the key displays a popup menu, and so on. If the key corresponds to no other function, Progress processes it as data input, with any required character validation.
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