Setting the screen resolution

[Andy]

Hi,

Happy new year to all!

My friend has a laptop, and she plugs in a TV to the external monitor connection on the laptop so she can watch films etc on the bigger TV screen.

But when she unplugs the TV, the laptop screen resolution does not revert back to the previous setting of
1024 x 768.

Is there a way of setting the screen resolution using IWB+ code so I can write a quick fix program?

She is not very compitant with computers, so asking her to reset the screen resolution herself is not really
an option for her.

She has Windows XP.

Thanks,
Andy.

[LarryMc]

The API you want to use is ChangeDisplaySettings

You shouldn't have any trouble converting this Creative Basic code by Sapero to what you want to do.

Code Select Expand

declare "user32", EnumDisplaySettingsA(lpszDeviceName:pointer,iModeNum:int,lpDevMode:memory),int
declare "user32", ChangeDisplaySettingsA(lpDevMode:memory, dwflags:int),int

const CCHDEVICENAME = 32
const ENUM_CURRENT_SETTINGS = -1

type DEVMODE,2
def dmDeviceName[CCHDEVICENAME]:char
def dmSpecVersion:word
def dmDriverVersion:word
def dmSize:word
def dmDriverExtra:word
def dmFields:int
def reserved[16]:int

def dmPelsWidth:int
def dmPelsHeight:int
def reserved2:int
def dmDisplayFrequency:int
endtype

def lpDevMode:memory
def dmCurrent:DEVMODE
def dmNew:DEVMODE
def NULL:pointer

allocmem(lpDevMode, 1, len(dmCurrent))
dmCurrent.dmSize = len(dmCurrent)
writemem lpDevMode, 1, dmCurrent
' get the current settings
EnumDisplaySettingsA(NULL, ENUM_CURRENT_SETTINGS, lpDevMode)
readmem lpDevMode, 1, dmCurrent
readmem lpDevMode, 1, dmNew

messagebox 0, using("#x#", dmCurrent.dmPelsWidth, dmCurrent.dmPelsHeight), "current display mode"


dmNew.dmPelsWidth = 640
dmNew.dmPelsHeight = 480
writemem lpDevMode, 1, dmNew
if (ChangeDisplaySettingsA(lpDevMode, 0) = 0)
messagebox 0, using("changed to #x#", dmNew.dmPelsWidth, dmNew.dmPelsHeight), ""
writemem lpDevMode, 1, dmCurrent
ChangeDisplaySettingsA(lpDevMode, 0)
else
messagebox 0, using("failed to switch to #x#", dmNew.dmPelsWidth, dmNew.dmPelsHeight), ""
endif

freemem lpDevMode


[Andy]

Thank Larry,

Will have a look at it!

Andy.

[Andy]

Thanks Larry,

Thats perfect for her.

Made two versions of the program, 1 to set the laptop resolution and 1 for the tv resolution, she just has to double click on the one she wants.

Thanks again,
Andy.

[LarryMc]

glad I could help.