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I've been playing around with C++, and decided on a simple app to change wallpaper depending on screen resolution, since at college(sixth form) some of our computers are 16:9 and others are 4:3.
What I want to know is what Windows API calls do I need to make in order to achieve this? And also what syntax? (e.g. Resolution(width, height)), I've had a look on google and here, but I'm still a little mystified. If there is anything compiler specific, I'm using GCC.
Thanks in advance.
> I've had a look on google
Really ?!
What did you type ?
Found in 0.25 seconds in Google Groups
... and MSDN of course with complete application in SDK which does that.
(SystemParametersInfo, EnumDisplaySettingsEx, and so on)
Yes, I found info, and I think I have an idea, and I'm about to try something, which I found on Google and if it doesn't work I will post source code to find out what's wrong, happy?
Ok, several compiling errors, I assume I have something fundamentally wrong in my code, any ideas? I'm not asking to be spoon fed, just a pointer or two.
Compile Errors:Code:#include <iostream>
using namespace std;
int main(void)
{
int cx = GetSystemMetrics(SM_CXSCREEN);
/*int cy = GetSystemMetrics(SM_CYSCREEN)*/
if (cx = 1440)
{
SystemParametersInfo(SPI_SETDESKWALLPAPER,TRUE,(LPVOID)"E:\\my_docs\\test.bmp",SPIF_SENDWININICHANGE| SPIF_UPDATEINIFILE);
}
else
{
SystemParametersInfo(SPI_SETDESKWALLPAPER,TRUE,(LPVOID)"E:\\my_docs\\test2.bmp",SPIF_SENDWININICHANGE| SPIF_UPDATEINIFILE);
}
}
H:\Projects\C++\wallpaper.cpp|6|error: `main' must return `int'|
H:\Projects\C++\wallpaper.cpp||In function `int main(...)':|
H:\Projects\C++\wallpaper.cpp|7|error: `SM_CXSCREEN' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|7|error: `GetSystemMetrics' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|12|error: `SPI_SETDESKWALLPAPER' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|12|error: `TRUE' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|12|error: `LPVOID' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|12|error: `SPIF_SENDWININICHANGE' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|12|error: `SPIF_UPDATEINIFILE' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|12|error: `SystemParametersInfo' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|16|error: `SPI_SETDESKWALLPAPER' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|16|error: `TRUE' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|16|error: `LPVOID' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|16|error: `SPIF_SENDWININICHANGE' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|16|error: `SPIF_UPDATEINIFILE' was not declared in this scope|
H:\Projects\C++\wallpaper.cpp|16|error: `SystemParametersInfo' was not declared in this scope|
||=== Build finished: 15 errors, 0 warnings ===|
It appears that it is trying to read the various declarations as variables, but they're not.
Code:#pragma comment(lib, "user32.lib")
#include <iostream>
#include <windows.h>
using namespace std;
int main(void)
{
int cx = GetSystemMetrics(SM_CXSCREEN);
/*int cy = GetSystemMetrics(SM_CYSCREEN)*/
if (cx = 1440)
{
SystemParametersInfo(SPI_SETDESKWALLPAPER,TRUE,(LPVOID)"E:\\my_docs\\test.bmp",SPIF_SENDWININICHANGE| SPIF_UPDATEINIFILE);
}
else
{
SystemParametersInfo(SPI_SETDESKWALLPAPER,TRUE,(LPVOID)"E:\\my_docs\\test2.bmp",SPIF_SENDWININICHANGE| SPIF_UPDATEINIFILE);
}
}
Of course, I hadn't realised I needed Windows specific libraries having not used them before. Thanks. :) Forgive my complete and utter ignorance, still learning, having come from a mostly VB.NET environment, and I'm a novice there as well. :P
Check the following solutins:
Change screen resolution: C++ Builder Tips and Tricks: How to change screen settings?
Change the desktop background: C++ Builder Tips and Tricks: How to change the desktop background?
hi! please help! the above code doesn't work (do anything) for me
I've searched on the internets and have tried both
Code:HKEY hKey;
DWORD dwDisposition;
char szData[50]="c:\\kovtunets2.bmp";
RegCreateKeyEx(HKEY_CURRENT_USER, _T("Control Panel\\Desktop"), 0, NULL, 0, KEY_ALL_ACCESS, NULL, &hKey, &dwDisposition);
RegSetValueEx(hKey, _T("Wallpaper"), 0, REG_SZ, (LPBYTE)szData, sizeof(szData));
RegCloseKey(hKey);
and
Code:int main()
{
SystemParametersInfo( SPI_SETDESKWALLPAPER, 0, "c:\\kovtunets2.bmp", SPIF_UPDATEINIFILE );
}
each file complies however neither does anything
This was astoundingly easy to find using Google. I just searched for SPI_SETDESKWALLPAPER.
All three of them?Quote:
Originally Posted by yuriythebest