General GWES Registry Settings (Windows CE 5.0)

Article
09/14/2012

The Graphics, Windowing, and Events Subsystem (GWES) module in Windows CE supports the windows, dialog boxes, controls, menus, and resources that make up the Windows CE user interface (UI).

General GWES-related settings are controlled by registry values under the following registry key.

[HKEY_LOCAL_MACHINE\SYSTEM\GWE]

General Settings

To set the height of the nonclient title bar, set the cyCap registry. The following code example shows how to set this registry value.

"cyCap"=dword:<height>

To specify the minimum height of the scroll thumb for multiple pages, set the cyThMin registry value. The following code example shows how to set this registry value.

"cyThMin"=dword:<height>

To specify that C++ Exception Handling (SEH) should not be used for validation, set the NoSEH registry value. Set this value to 1 to specify that C++ Exception Handling should not be used for validation or set the value to 0 to allow the use of C++ Exception Handling for validation.

"NoSEH"=dword:<0|1>        // Do not use SEH for validation

To specify the default height of the scroll thumb, set the cyThDef registry value. The following code example shows how to set this registry value.

"cyThDef"=dword:<height>

To specify the size of widget images for nonclient buttons and menu check marks, set the WidgSz registry value. Set this registry value to 0 to specify normal size images or set it to 1 to specify large images. The following code example shows how to set this registry value.

"WidgSz"=dword:1

To specify the width of a nonclient button, set the cxWidg registry value. The following code example shows how to set this registry value.

"cxWidg"=dword:<height>

To set the width and height of the arrow bitmap on a horizontal scroll bar, set the cxHScr and cyHScr registry values. To set the width and height of the arrow bitmap on a vertical scroll bar, set the cxVScr and cyVScr registry values. The following code example shows how to set these registry values.

"cxHScr"=dword:<width>
"cyHScr"=dword:<height>
"cxVScr"=dword:<width>
"cyVScr"=dword:<height>

To specify the system colors, set the SysColor registry value. The following code example shows how to set this registry value.

"SysColor"=hex:E0,E0,E0,00, 00,80,80,00, 80,80,FF,00, 80,80,80,00,
               C0,C0,C0,00, FF,FF,FF,00, 00,00,00,00, 00,00,00,00,
               00,00,00,00, FF,FF,00,00, C0,C0,C0,00, C0,C0,C0,00,
               80,80,80,00, 00,00,FF,00, FF,FF,00,00, C0,C0,C0,00,
               80,80,80,00, 80,80,80,00, 00,00,00,00, C0,C0,C0,00,
               FF,FF,FF,00, 00,00,00,00, DF,DF,DF,00, 00,00,00,00,
               FF,FF,E1,00

For more information about the SysColor registry value, see Customizing System Colors.

To enable repainting when power to the target device is applied, set the PORepaint registry value. The following table shows the available values for PORepaint.

Value	Description
0	The display driver handles all suspend and resume operations.
1	GWE should save and restore the entire screen.
2	GWE should invalidate and repaint the entire screen.
3	GWE and the driver need to save video memory.

The default value is 1. The following code example shows how to set this registry value.

"PORepaint"=dword:1

In general, use the values 0 or 3 for display drivers that can allocate video memory for surfaces other than the desktop. Setting the value to 2 uses the least amount of system memory, but forces all applications to redraw all visible windows. Setting the value to 1 uses extra memory (equal to screen width * screen height * bytes per pixel) and does not force all applications to redraw visible windows.

To specify the number of milliseconds before search mode of a list box terminates, set the dtLBSrch registry value. The default value is 1000. The following code example shows how to set this registry value.

"dtLBSrch"=dword:<milliseconds>

The following registry key example shows how to customize general GWES settings.

[HKEY_LOCAL_MACHINE\SYSTEM\GWE]
    "cyCap"=dword:2A
    "WidgSz"=dword:1
    "cyThMin"=dword:15
    "cyThDef"=dword:32
    "cxWidg"=dword:32
    "cxHScr"=dword:38
    "cyHScr"=dword:38
    "cxVScr"=dword:38
    "cyVScr"=dword:38
    "SysColor"=hex:E0,E0,E0,00, 00,80,80,00, 80,80,FF,00, 80,80,80,00,
                   C0,C0,C0,00, FF,FF,FF,00, 00,00,00,00, 00,00,00,00,
                   00,00,00,00, FF,FF,00,00, C0,C0,C0,00, C0,C0,C0,00,
                   80,80,80,00, 00,00,FF,00, FF,FF,00,00, C0,C0,C0,00,
                   80,80,80,00, 80,80,80,00, 00,00,00,00, C0,C0,C0,00,
                   FF,FF,FF,00, 00,00,00,00, DF,DF,DF,00, 00,00,00,00,
                   FF,FF,E1,00

Window Animations

To enable window animations, set the Animate registry value. Set this registry value to 1 to turn window animations on or set the value to 0 to turn window animations off. The following code example shows how to set this registry value.

"Animate"=dword:1

To control the characteristics of window animations, set the HKEY_LOCAL_MACHINE\SYSTEM\GWE\ANIMATE\Frames and HKEY_LOCAL_MACHINE\SYSTEM\GWE\ANIMATE\DelayMilliseconds registry values. The Frames value specifies the number of frames in the animation, and the DelayMilliseconds value specifies the period of time between the display of successive frames in the animation. The following code example shows how to set these registry values.

[HKEY_LOCAL_MACHINE\SYSTEM\GWE\ANIMATE]
    "Frames"=dword:5
    "DelayMilliseconds"=dword:a

Menus

This registry setting allows OEMs to provide overlapping menus, which is useful for small screen target devices. The following registry key controls the overlap.

HKEY_LOCAL_MACHINE\System\GWE\Menu\Overlap

The default value for overlap is set to 60.

Message Boxes

To hide the Cancel button on a message box and remap the functionality of the button, set the HKEY_LOCAL_MACHINE\SYSTEM\GWE\MsgBox\NoCancelText registry value. To hide the Ignore button on a message box and remap the functionality of the button, set the HKEY_LOCAL_MACHINE\SYSTEM\GWE\MsgBox\NoIgnoreText registry value. The following code example shows how to set these registry values.

[HKEY_LOCAL_MACHINE\SYSTEM\GWE\MsgBox]
    "NoCancelText"="This text is appended to the message text."
    "NoIgnoreText"="\nThis text shows on a different line than the message text."

For more information about the NoCancelText and NoIgnoreText registry settings, see Reducing the Size of Message Boxes.

To specify the rectangle in which to center message boxes, set the HKEY_LOCAL_MACHINE\System\GWE\DlgCtr registry value. The following code example shows how to set this registry value.

"DlgCtr"=hex:00,00,00,00,00,00,00,00,f0,00,00,00,78,00,00,00

For more information about the DlgCtr registry value, see Positioning Message Boxes.

Notification

Notification-related settings are controlled by registry values under the HKEY_LOCAL_MACHINE\SYSTEM\GWE\Notify registry key.

To specify the name of the file that stores the notification databases, set the Volume registry value. If the Volume key does not exist, the operating system (OS) creates a database named DB_notify_queue in the object store by default. The following registry key example shows how to set this registry value.

"volume"="\\hard disk\\notify.db"

To specify the delay for blocking the CeEventHasOccured function while the OS initializes, in milliseconds, set the ShortApiTimeout registry value. The default value for ShortApiTimeout is 5000 milliseconds. The following code example shows how to set this registry value.

"ShortApiTimeout"=DWORD:5000

To specify the delay to block all other APIs while the OS initializes, in milliseconds, set the LongApiTimeout registry value. The default value for LongApiTimeout is 15000 milliseconds. The following code example shows how to set this registry value.

"LongApiTimeout"=DWORD:15000

To specify the delay for which the OS should wait for external file systems to initialize, in milliseconds, set the MountTimeout registry value. The default value for MountTimeout is 20000 milliseconds. MountTimeout determines how many times the OS attempts to mount the database volume. After each attempt, the thread that is trying to mount the volume waits for 5000 milliseconds before the next attempt. This means that the OS makes a maximum of MountTimeout/5000 attempts to mount a database volume. The following code example shows how to set this registry value.

"MountTimeout"=DWORD:20000

To control whether an error message box is displayed by the notification subsystem, set the ShowErrorUI registry entry. Setting this entry to zero disables the error message box, and a nonzero value will enable it.

The following example shows how to enable the error message box.

"ShowErrorUI"=DWORD:1