Changing Desktop WallPaper on the fly ... i try but...

GregBUG · Post by **GregBUG** » Tue Aug 17, 2004 12:36 pm

i try with

SystemParametersInfo_(#SPI_SETDESKWALLPAPER, 0, "C:\Myphoto.jpg", #SPIF_UPDATEINIFILE | #SPIF_SENDWININICHANGE)

but it don't work!

i use winxp.

can you help me?

Thanks!

Ciao Gianluca.

Max.Â² · Post by **Max.Â²** » Tue Aug 17, 2004 12:52 pm

Try with a bitmap (.bmp) instead of jpg...

GregBUG · Post by **GregBUG** » Wed Aug 18, 2004 6:15 pm

ok. now work fine. thanks!

How can i set the property stretched or "placed side by side" ?

i searched in the windows api but i can't find...

many thanks!

Sparkie · Post by **Sparkie** » Thu Aug 19, 2004 2:39 pm

Let me preface by saying I don't know much about the IActiveDesktop interface, but thanks to our fellow PBer's, sec, Justin, freak, and blueznl in a related thread, I've managed to whip up some code that allows wallpaper in either .bmp or .jpg format and lets you set the Stretch, Tile, or Center options.

This code does not remember your original wallpaper settings so make sure you have the path to your current wallpaper handy if you want to restore it as your default wallpaper.

I'm still a little fuzzy on the difference between bstr and unicode. Anyone care to clear that up for me in regards to memory allocation? It seems to work fine here on Win98fe and WinXPhome with PB 3.91, but I want to make sure I'm doing it right,

Code: Select all

#WPSTYLE_CENTER = 0
#WPSTYLE_TILE = 1
#WPSTYLE_STRETCH = 2
#WPSTYLE_MAX = 3

#AD_APPLY_SAVE = 1
#AD_APPLY_HTMLGEN = 2
#AD_APPLY_REFRESH = 4
#AD_APPLY_FORCE = 8
#AD_APPLY_ALL = #AD_APPLY_SAVE | #AD_APPLY_HTMLGEN | #AD_APPLY_REFRESH

Structure myWALLPAPEROPT
  dwSize.l
  dwStyle.l
EndStructure

wallpaperOptions.myWALLPAPEROPT
wallpaperOptions\dwSize = SizeOf(myWALLPAPEROPT)

CoInitialize_(0) 

If CoCreateInstance_(?CLSID_ActiveDesktop,0,1,?IID_IActiveDesktop,@deskObj.IActiveDesktop) <> #S_OK
  MessageRequester("Error", "Could not create object")
  quit = #True
EndIf

Global wallpaperOptions, deskObj

Procedure doWallpaper(myWallpaper$)
  ; get option selection
  If GetGadgetState(2)
    wallpaperOptions\dwStyle = #WPSTYLE_TILE
  ElseIf GetGadgetState(3)
    wallpaperOptions\dwStyle = #WPSTYLE_STRETCH
  Else
    wallpaperOptions\dwStyle = #WPSTYLE_CENTER
  EndIf
  
  ; allocate for wStr filename
  filenameWide = AllocateMemory(Len(myWallpaper$)*2+2) 
  MultiByteToWideChar_(#CP_ACP, 0, @myWallpaper$, -1, filenameWide, Len(myWallpaper$)*2+2)                
   
    If deskObj\SetWallpaper(filenameWide, 0) = #S_OK
    
      If deskObj\SetWallpaperOptions(@wallpaperOptions, 0) =#S_OK
      
        If deskObj\ApplyChanges(#AD_APPLY_SAVE) <> #S_OK
          MessageRequester("Error", "Unable to apply changes to Wallpaper.")
        EndIf
      
      EndIf
      
    EndIf
  FreeMemory(filenameWide)
 
ProcedureReturn 0
EndProcedure

If OpenWindow(0, 10, 10, 200, 150, #PB_Window_SystemMenu | #PB_Window_ScreenCentered, "Change Wallpaper") 
  
  If CreateGadgetList(WindowID()) 
    
    ButtonGadget(1, 50, 10, 100, 40, "Select Wallpaper") 
    OptionGadget(2, 60, 60, 100, 20, "Tile")
    OptionGadget(3, 60, 90, 100, 20, "Stretch")
    OptionGadget(4, 60, 120, 100, 20, "Center")
    SetGadgetState(3,1)
    
  EndIf 
  
EndIf 

Repeat 
  
  Event = WaitWindowEvent() 
 
  Select Event 
    
    Case #PB_EventGadget
      
      Select EventGadgetID()
        
        Case 1
          wallpaper$ = Space(#MAX_PATH)
          wallpaper$ = OpenFileRequester("Select Wallpaper", "c:\", "*.bmp *.jpg *.jpeg | *.bmp;*.jpg", 0 )
          If wallpaper$
            doWallpaper(wallpaper$)
          EndIf
        
        Case 2
          If wallpaper$
            doWallpaper(wallpaper$)
          EndIf
          
        Case 3
          If wallpaper$
            doWallpaper(wallpaper$)
          EndIf
          
        Case 4
          If wallpaper$
            doWallpaper(wallpaper$)
          EndIf
          
      EndSelect
      
    Case #PB_Event_CloseWindow 
      quit = #True 
      
  EndSelect 
  
Until quit = #True 


If deskObj
  deskObj\release() 
EndIf

CoUninitialize_() 

End

DataSection 
CLSID_ActiveDesktop: 
Data.l $75048700 
Data.w $EF1F,$11D0 
Data.b $98,$88,$00,$60,$97,$DE,$AC,$F9 

IID_IActiveDesktop: 
Data.l $F490EB00 
Data.w $1240,$11D1 
Data.b $98,$88,$00,$60,$97,$DE,$AC,$F9 
EndDataSection

GregBUG · Post by **GregBUG** » Thu Aug 19, 2004 2:49 pm

thank you!

it work fine here! (winXP PRO & WinME)

ricardo · Post by **ricardo** » Thu Sep 20, 2007 5:03 am

I get invalid memory acces here in PB 4:

Code: Select all

If deskObj\SetWallpaper(filenameWide, 0) = #S_OK

Any advice?

Kaeru Gaman · Post by **Kaeru Gaman** » Thu Sep 20, 2007 1:15 pm

@Sparkie

would you mind pointing out the Commands that access the the Stretch, Tile, or Center options?

...I'm not interested in ActiveDesktop (gosh I hate that crap. Vade Retro, Satanas)
I had really BAD experiences with this, and I will not try a Code that may change my Desktop to "Active".

but I'm interested how to set the Options additionally to the Background Pic.

ebs · Post by **ebs** » Thu Sep 20, 2007 2:45 pm

@Kaeru,

If you can use Windows API calls, this code works on Win XP, and probably Win 2000 as well. I don't know about Vista.

Code: Select all

; set registry keys for center/tile/stretch
If RegOpenKeyEx_(#HKEY_CURRENT_USER, "Control Panel\\Desktop\\", 0, #KEY_ALL_ACCESS, @key.l) = #ERROR_SUCCESS

  Select WPType
    Case "c"	; center
      TileWP.s = "0"
      WPStyle.s = "1"
    Case "t"	; tile
      TileWP.s = "1"
      WPStyle.s = "0"
    Case "s"	; stretch
      TileWP.s = "0"
      WPStyle.s = "2"
  EndSelect 

  RegSetValueEx_(key, "TileWallpaper", 0, #REG_SZ, TileWP, 2)
  RegSetValueEx_(key, "WallpaperStyle", 0, #REG_SZ, WPStyle, 2)

EndIf

Regards,
Eric

Kaeru Gaman · Post by **Kaeru Gaman** » Thu Sep 20, 2007 2:51 pm

thnx Eric

Sparkie · Post by **Sparkie** » Thu Sep 20, 2007 3:47 pm

@ebs: Thank you

@Kaeru Gaman: Sorry I was late

@ricardo: See if this works any better for you...

Code: Select all

;...Wallpaper changer by Sparkie

#WPSTYLE_CENTER = 0 
#WPSTYLE_TILE = 1 
#WPSTYLE_STRETCH = 2 
#WPSTYLE_MAX = 3 

#AD_APPLY_SAVE = 1 
#AD_APPLY_HTMLGEN = 2 
#AD_APPLY_REFRESH = 4 
#AD_APPLY_FORCE = 8 
#AD_APPLY_BUFFERED_REFRESH = 10
#AD_APPLY_COMPLETEREFRESH = 20
#AD_APPLY_DYNAMICREFRESH = 20
#AD_APPLY_ALL = #AD_APPLY_SAVE | #AD_APPLY_HTMLGEN | #AD_APPLY_REFRESH 

Structure myWALLPAPEROPT 
  dwSize.l 
  dwStyle.l 
EndStructure 

Global wallpaperOptions.myWALLPAPEROPT 
Global deskObj.IActiveDesktop 
CoInitialize_(0) 

If CoCreateInstance_(?CLSID_ActiveDesktop,0,1,?IID_IActiveDesktop,@deskObj.IActiveDesktop) <> #S_OK 
  MessageRequester("Error", "Could not create object") 
  Quit = #True 
EndIf 

Procedure doWallpaper(myWallpaper$) 
  wallpaperOptions\dwSize = SizeOf(myWALLPAPEROPT) 
  ;... get option selection 
  If GetGadgetState(2) 
    wallpaperOptions\dwStyle = #WPSTYLE_TILE 
  ElseIf GetGadgetState(3) 
    wallpaperOptions\dwStyle = #WPSTYLE_STRETCH 
  Else 
    wallpaperOptions\dwStyle = #WPSTYLE_CENTER 
  EndIf 
  ;... allocate for wStr filename 
  *filenameWide = AllocateMemory(Len(myWallpaper$)*2+2) 
  PokeS(*filenameWide, myWallpaper$, -1, #PB_Unicode)
  If deskObj\SetWallpaperOptions(@wallpaperOptions, 0) = #S_OK 
    If deskObj\SetWallpaper(*filenameWide, 0) = #S_OK 
      If deskObj\ApplyChanges(#AD_APPLY_ALL) <> #S_OK 
        MessageRequester("Error", "Unable to apply changes to Wallpaper.") 
      EndIf 
    EndIf 
  EndIf 
  FreeMemory(*filenameWide) 
  ProcedureReturn 0 
EndProcedure 

If OpenWindow(0, 10, 10, 200, 150, "Change Wallpaper", #PB_Window_SystemMenu | #PB_Window_ScreenCentered) And CreateGadgetList(WindowID(0)) 
  ButtonGadget(1, 50, 10, 100, 40, "Select Wallpaper") 
  OptionGadget(2, 60, 60, 100, 20, "Tile") 
  OptionGadget(3, 60, 90, 100, 20, "Stretch") 
  OptionGadget(4, 60, 120, 100, 20, "Center") 
  SetGadgetState(3,1) 

  Repeat 
    event = WaitWindowEvent() 
    Select event 
      Case #PB_Event_Gadget 
        Select EventGadget() 
          Case 1 
            wallpaper$ = Space(#MAX_PATH) 
            wallpaper$ = OpenFileRequester("Select Wallpaper", "c:\", "*.bmp *.jpg *.jpeg | *.bmp;*.jpg", 0 ) 
            If wallpaper$ 
              doWallpaper(wallpaper$) 
            EndIf 
          Case 2 
            If wallpaper$ 
              doWallpaper(wallpaper$) 
            EndIf 
          Case 3 
            If wallpaper$ 
              doWallpaper(wallpaper$) 
            EndIf 
          Case 4 
            If wallpaper$ 
              doWallpaper(wallpaper$) 
            EndIf 
        EndSelect 
      Case #PB_Event_CloseWindow 
        Quit = #True 
    EndSelect 
  Until Quit = #True 

  If deskObj 
    deskObj\Release() 
  EndIf 
  CoUninitialize_() 
EndIf
End 

DataSection 
CLSID_ActiveDesktop: 
Data.l $75048700 
Data.w $EF1F,$11D0 
Data.b $98,$88,$00,$60,$97,$DE,$AC,$F9 

IID_IActiveDesktop: 
Data.l $F490EB00 
Data.w $1240,$11D1 
Data.b $98,$88,$00,$60,$97,$DE,$AC,$F9 
EndDataSection

ricardo · Post by **ricardo** » Thu Sep 20, 2007 10:18 pm

Excellent Sparkie!!

Thanks

Sparkie · Post by **Sparkie** » Fri Sep 21, 2007 3:01 am

You're welcome

Kaeru Gaman · Post by **Kaeru Gaman** » Fri Sep 21, 2007 10:05 am

Sparkie wrote:@Kaeru Gaman: Sorry I was late

no problem...

additional question:

is there a way to
- change wallpaper via registry
- change tilings via SystemParametersInfo_
?

Gregs Attempt to change wallpaper uses SystemParametersInfo_,
Erics solution for tiling uses registry entries.

is it possible to do both the same way?

Sparkie · Post by **Sparkie** » Fri Sep 21, 2007 1:18 pm

SystemParametersInfo_ () should work if you select a BMP rather than a JPG image. You can then use the Registry to set the style as desired.

Kaeru Gaman wrote:...and I will not try a Code that may change my Desktop to "Active".

I completely understand your point of view on Active Desktop. I can't guarantee you the same success as me, but I do NOT have Active Desktop enabled on my XP system and my code above works just fine with no problems.