Most dialog boxes have OK and CANCEL buttons, and Windows provides predefined symbols for these ubiquitous elements.
You will use the predefined symbol IDOK for an OK button in your dialog. When the user presses ENTER, Windows sends your dialog procedure a message as if the OK button had been pressed. IDOK has an ID value of 1.
You will use IDCANCEL for a CANCEL button in your dialog. When the user presses ESC, it's as if the CANCEL button has been pressed. IDCANCEL has an ID value of 2.
Some controls don't need a unique identifier. For example, you won't usually need to access a group box frame, which simply frames other controls. You can assign all such controls the symbol UNUSED, which has an ID value of –1.
Summary: Enter a symbol and label text.
The Properties Bar Text field contains the button's default text, “Push.” Assign the symbol IDOK to your first push button, give it the text OK (see Figure 1.4), and then press ENTER.