National Instruments 320682C

Chapter 8 Utility Library

• The <Alt-Tab>, <Alt-Esc>, or <Ctrl-Esc> key combination under Windows 3.1 or Windows 95.

• The Switch To item in the system menu under Windows 3.1.

This function affects the behavior of these keys only while LabWindows/CVI or a

LabWindows/CVI Standalone Executable is the active application under Microsoft Windows.

This function has no effect in Windows NT. See the Alternatives in Windows NT section for

instructions on how to achieve the desired effect.

Note: To use this function on Windows 95, the LabWindows/CVI low-level support driver

must be loaded.

Disabling the Task List

DisableTaskSwitching does not prevent the user from clicking on the desktop to get the

task list in Windows 3.1, or clicking on the task bar in Windows 95. You can prevent the user

from clicking on the desktop by forcing your window to cover the entire screen.

Forcing Window to Cover Entire Screen

You can force your window to cover the entire screen by making the following calls to functions

in the User Interface Library.

SetPanelAttribute (panel, ATTR_SIZABLE, FALSE);

SetPanelAttribute (panel, ATTR_CAN_MINIMIZE, FALSE);

SetPanelAttribute (panel, ATTR_CAN_MAXIMIZE, FALSE);

SetPanelAttribute (panel, ATTR_SYSTEM_MENU_VISIBLE, FALSE);

SetPanelAttribute (panel, ATTR_MOVABLE, FALSE);

SetPanelAttribute (panel, ATTR_WINDOW_ZOOM, VAL_MAXIMIZE);

In these calls, panel is the panel handle for your top-level window. These calls will work in

Windows 3.1, Windows 95, and Windows NT.

Alternatives in Windows 3.1

Under Windows 3.1, you can prevent the end-user accessing the task list by disabling the Task

Manager. Change a line in your system.ini [boot] section from

taskman.exe = taskman.exe

taskman.exe =

Forcing your window to cover the entire screen or disabling the Task Manager does not prevent

the user from task switching using the <Alt-Tab> and <Alt-Esc> key combinations. You must

also call DisableTaskSwitching to disable the <Alt-Tab> and <Alt-Esc> key

combinations. As an alternative to calling DisableTaskSwitching, you can arrange for