How to get lpFaceName from choosefont

[Gösta H. Lovgren-2]

I just posted a Choose Font Include file which may answer some questions:

http://www.powerbasic.com/support/pbforums/showthread.php?t=40352

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"If you want to make an apple pie from scratch,
you must first create the universe."
Carl Sagan
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[Edwin Knoppert]

Of course everything should be set 100% but it might be a better idea to read the contents from lf and not via the pointer.
It more logical since you pass this pointer only to set this lf type var. but not to use it.
But then, if it crashes or not, it should be written correctly after all.

[Michael Mattias]

You get/don't get a GPF depending on your #DEBUG ERROR setting.

This line...

fcnm$ = cf.[COLOR="Red"]@lplogfont[/COLOR].lfFaceName

.. is the crux of the issue.

When you don't set the LOGFONT PTR member of the CHOOSEFONT structure, you have a null pointer at "@plogFont".

With #DEBUG ERROR ON, because the pointer is null the statement is not attempted and ERROR 9 is set. Without this setting, the program attempts to read memory using a null pointer... which is a protection fault since you don't own the memory at 0x00000000

MCM

[Fred Buffington]

Thanks edwin. I didnt get a GPF and it does work. Using version 8.01 for this instead of 9.01.

I had put in the
local lf as logfont

but failed to add
cf.lpLogFont = VARPTR(lf)

Thanks also to Peter and Michael.

[Edwin Knoppert]

You get a gpf, this seems to work but i didn't check msdn to verify all poss. errors:

  ' and the incredibly complicated code for what WinMain does:
  Local cf As choosefontapi       ' comdlg32
  Local lf As logfont

  cf.lstructSize  = SizeOf(cf)
  cf.flags        = %CF_BOTH Or %CF_EFFECTS

  cf.lplogfont = VarPtr( lf )

  Function = ChooseFont(cf)
  Local  ips&, fcnm$
  
  ips&=cf.ipointsize
  fcnm$ = [email protected]
  MsgBox Str$(ips&)+fcnm$

  Function = 5

Edit: crosspost, similar answer as above

[Peter Jinks]

Hi Fred,

You need to provide the LOGFONT structure for the API to populate with data (currently the lpLogFont member points nowhere). Try this:

#COMPILE EXE
#DEBUG ERROR ON
#REGISTER NONE

#INCLUDE  "WIN32API.INC"    ' file date: 2/25/02 (PB version date).
#INCLUDE "COMDLG32.INC"
#RESOURCE "CHOOSE_FONT.PBR"


FUNCTION WINMAIN (BYVAL hInstance     AS LONG, _
                  BYVAL hPrevInstance AS LONG, _
                  BYVAL lpCmdLine     AS ASCIIZ PTR, _
                  BYVAL iCmdShow      AS LONG) AS LONG
  ' and the incredibly complicated code for what WinMain does:
  LOCAL cf AS choosefontapi       ' comdlg32
  LOCAL lf AS LOGFONT         '<---- added
  cf.lpLogFont = VARPTR(lf)         '<---- added
  cf.lstructSize  = SIZEOF(cf)
  cf.flags        = %CF_BOTH OR %CF_EFFECTS

  FUNCTION = ChooseFont(cf)
  ips&=cf.ipointsize
  fcnm$ = [email protected]
  MSGBOX STR$(ips&)+fcnm$

  FUNCTION = 5


END FUNCTION

Regards,

Pete.

[Fred Buffington]

Thanks edwin, I had the @ sign in the wrong place. Thanks.

Well, it didnt come back with anything.
Here is the code (from Michael's example)

#COMPILE EXE
#DEBUG ERROR ON
#REGISTER NONE

#INCLUDE  "WIN32API.INC"    ' file date: 2/25/02 (PB version date).
#INCLUDE "COMDLG32.INC"
#RESOURCE "CHOOSE_FONT.PBR"


FUNCTION WINMAIN (BYVAL hInstance     AS LONG, _
                  BYVAL hPrevInstance AS LONG, _
                  BYVAL lpCmdLine     AS ASCIIZ PTR, _
                  BYVAL iCmdShow      AS LONG) AS LONG
  ' and the incredibly complicated code for what WinMain does:
  LOCAL cf AS choosefontapi       ' comdlg32
  cf.lstructSize  = SIZEOF(cf)
  cf.flags        = %CF_BOTH OR %CF_EFFECTS

  FUNCTION = ChooseFont(cf)
  ips&=cf.ipointsize
  fcnm$ = [email protected]
  MSGBOX STR$(ips&)+fcnm$

  FUNCTION = 5


END FUNCTION

but the fcnm$ returns nothing. The ips& comes back correctly as point size in decipoints (140 for 14 etc)

[Edwin Knoppert]

lfFaceName As Asciiz * %LF_FACESIZE
and thus no pointer..

If lplogfont in choosefontapi.lplogfont is a pointer use @

A$ = [email protected]

[Fred Buffington]

I want to use a user selectable font option and choosefont is easy to
use. I can't seem to figure out, though how to get the chosen lpfacename
from the choosefontapi.lplogfont pointer to lpfacename
in the logfont type def.