Lock system keys

You can restrict operator access to standard Windows functions by disabling system keys on the computer running an InTouch application. For example, you can prevent an operator from using the Windows CTRL+ALT+DEL key combination to show the Task Manager dialog box. Disabling system keys prevents operators from switching from the InTouch HMI to another Windows application.

WindowViewer has key filter options that set the default state of system keys when an InTouch application starts. A key filter disables a system key when it is active.

Disable system keys based on what tasks you expect your various InTouch users to complete. Most function keys should be disabled for operators. Administrators still need function keys for their InTouch tasks.

You can write a script that enables or disables system keys based on the access level of the person logging on to WindowViewer. Use the EnableDisableKeys() function in a script to selectively enable or disable Windows function keys.

Enable key filters

1. Open WindowMaker.

2. On the File menu, select Configure, and then select WindowViewer.

   The WindowViewer configuration screen appears.

3. Select the Window tab.

   

4. In the Miscellaneous area, disable WindowViewer system keys. Do the following:

   • Clear the Enable Fast Switch check box to remove the Development button from WindowViewer that switches the user to WindowMaker.

   • Select the Disable ALT key check box to disable the ALT key on the computer running the InTouch application.

   • Select the Disable WIN key check box to disable the WIN key on the computer running the InTouch application.

   • Select the Disable ESC key check box to disable the ESC key on the computer running the InTouch application.

5. Select OK.

6. Write a script that runs when WindowViewer starts running the InTouch application.

   The script should include statements to dynamically lock or unlock key based on the access level of the person who logged on to WindowViewer.

   Include the EnableDisableKeys() function within the script to enable/disable the ALT, ESC, and WIN keys. The EnableDisableKeys() function enables or disables system keys based on the discrete values of its arguments:

   EnableDisableKeys(AltKey,EscKey,WinKey);

   An argument value of 1 enables the key filter to disable the key.