determining dimensions for LABEL based upon size of text

[Bern Ertl]

I'd like to create a dialog that includes labels that are sized appropriately according to the size of the text that needs to be displayed. The text is not known at compile time (it's variable).

How can I determine (programmatically) how large (wide) the label control needs to be assuming I want just one line (no line breaks)?

[Erich Schulman]

It might not be possible unless you use a monospace font. If using a proportional font, you would have to know the width of every character and know the kerning. You could probably obtain that information from the font. If so, it should be possible albeit a lot of work. If not, you may well be out of luck without a monospace font.

[colin glenn]

I think you might be able to use this: DrawTextEx
With the dwDTFormat set to DT_CALCRECT
There might more parameters which need to be set when using the call for determining the size of a string of text, I used either this or something like this somewhere in one of my programs.

[Michael Mattias]

"The GetTextExtentPoint32 function computes the width and height of the specified string of text. "

---Windows SDK----

[Chris Holbrook]

There is also the DDT GRAPHIC TEXT SIZE STATEMENT, I think that you will need a GRAPHIC WINDOW to it this way. If using drawtextEX, note that you don't actually draw any text when the dt_calcrect flag is used. This fools everyone once.

[colin glenn]

And of course, with any of the SDK functions, you need to have the font you're working with selected into the device context for the function to return the results you're expecting.

[Bern Ertl]

I'm trying DrawTextEx, but it appears to be returning a width that is twice what it should be.

#COMPILE EXE
#DIM ALL

'--------------------------------------------------------------------------------
'   ** Includes **
'--------------------------------------------------------------------------------
#IF NOT %DEF(%WINAPI)
	#INCLUDE "WIN32API.INC"
#ENDIF
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
'   ** Constants **
'--------------------------------------------------------------------------------
%IDD_DIALOG1   = 101
%IDC_TEXTBOX1  = 1001
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
'   ** Declarations **
'--------------------------------------------------------------------------------
DECLARE CALLBACK FUNCTION ShowDIALOG1Proc()
DECLARE FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
FUNCTION PBMAIN()
	ShowDIALOG1 %HWND_DESKTOP
END FUNCTION
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
'   ** CallBacks **
'--------------------------------------------------------------------------------
CALLBACK FUNCTION ShowDIALOG1Proc()

	SELECT CASE CBMSG
		CASE %WM_COMMAND
			SELECT CASE CBCTL
				CASE %IDOK
					IF CB.CTLMSG = %BN_CLICKED OR CB.CTLMSG = 1 THEN
						DIALOG END CB.HNDL, 1
					END IF
				CASE %IDCANCEL
					IF CB.CTLMSG = %BN_CLICKED OR CB.CTLMSG = 1 THEN
						DIALOG END CB.HNDL, 0
					END IF
			END SELECT
	END SELECT

END FUNCTION
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
'   ** Dialogs **
'--------------------------------------------------------------------------------
FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG
	LOCAL lRslt AS LONG
	LOCAL hDlg AS DWORD

	LOCAL sTemp AS STRING, sLabel AS STRING
	LOCAL lRect AS RECT

	LOCAL I AS LONG, J AS LONG

	I = 1

	DIALOG NEW hParent, "Test", , , 255, 47 + I * 20, %WS_POPUP OR _
						%WS_DLGFRAME OR %WS_CAPTION OR %WS_SYSMENU OR %WS_MINIMIZEBOX OR _
						%WS_VISIBLE OR %DS_CENTER OR %DS_3DLOOK OR %DS_NOFAILCREATE OR _
						%DS_SETFONT, %WS_EX_WINDOWEDGE OR %WS_EX_LEFT OR %WS_EX_LTRREADING OR _
						%WS_EX_RIGHTSCROLLBAR, TO hDlg

	sLabel = "Description:"
	IF ISFALSE DrawTextEx( GetDC( hDlg), BYVAL STRPTR( sLabel), LEN( sLabel), lRect, %DT_CALCRECT, BYVAL 0) THEN lRect.nRight = 40

	CONTROL ADD LABEL, hDlg, -1, sLabel, 5, 5, lRect.nRight, 13, %WS_CHILD _
							 OR %WS_VISIBLE, %WS_EX_LEFT OR %WS_EX_LTRREADING
	CONTROL ADD TEXTBOX, hDlg, %IDC_TEXTBOX1, "", lRect.nRight + 10, 4, 235 - lRect.nRight, 13

	I = 10 + I * 20
	CONTROL ADD BUTTON, hDlg, %IDOK, "&OK", 10, I, 70, 25
	CONTROL ADD BUTTON, hDlg, %IDCANCEL, "&Cancel", 180, I, 65, 25

	DIALOG SHOW MODAL hDlg, CALL ShowDIALOG1Proc TO lRslt

	FUNCTION = lRslt
END FUNCTION
'--------------------------------------------------------------------------------

[Michael Mattias]

DrawTextExt
....
lprc
[in/out] Pointer to a RECT structure that contains the rectangle, in logical coordinates, in which the text is to be formatted.

I think "logical units" means pixels. Your dialog is using UNITS (by default).

[Bern Ertl]

I tried adding:

DIALOG PIXELS hDlg, lRect.nRight, lRect.nBottom TO UNITS lRect.nRight, lRect.nBottom

to the code and it appears to have reduced the value of lRect.nRight by 1/4, so it's still ~50% too large.

[Charles Dietz]

I think you need to fold in the current DDT font... something like this:

	DIALOG NEW hParent, "Test", , , 255, 47 + I * 20, %WS_POPUP OR _
						%WS_DLGFRAME OR %WS_CAPTION OR %WS_SYSMENU OR %WS_MINIMIZEBOX OR _
						%WS_VISIBLE OR %DS_CENTER OR %DS_3DLOOK OR %DS_NOFAILCREATE OR _
						%DS_SETFONT, %WS_EX_WINDOWEDGE OR %WS_EX_LEFT OR %WS_EX_LTRREADING OR _
						%WS_EX_RIGHTSCROLLBAR, TO hDlg

	sLabel = "Description:"
	hdc = GetDC(hDlg): sLen = LEN(sLabel)
   DIALOG SEND hDlg, %WM_GETFONT, 0, 0 TO hFont
   SelectObject hdc, hFont
	n = DrawTextEx(BYVAL hdc, BYVAL VARPTR(sLabel), BYVAL sLen+1, lRect, %DT_CALCRECT, BYVAL 0)
	DIALOG PIXELS hDlg, lRect.nRight, lRect.nLeft TO UNITS lRect.nRight, lRect.nLeft
	nWidth = lRect.nRight - lRect.nLeft
	IF n = 0 THEN lRect.nRight = 40

	CONTROL ADD LABEL, hDlg, -1, sLabel, 5, 5, nWidth, 13, %WS_CHILD _
							 OR %WS_VISIBLE, %WS_EX_LEFT OR %WS_EX_LTRREADING
	CONTROL ADD TEXTBOX, hDlg, %IDC_TEXTBOX1, "", 5 + nWidth, 4, 235 - lRect.nRight, 13

[colin glenn]

You should not need to select the font into the DC, it should already be in the DC because you're getting the DC for the dialog.

With that in mind:

Don't forget to ReleaseDC when done with the DC.

Before releasing any DC, ensure that you put back in the things which you "removed" when you selected them into the DC. That is:

hDC = GetDC(hDialog)
oldFont = SelectObject(hDC, myFont)
' do stuff
SelectObject hDC, oldFont
ReleaseDC hDialog, hDC

And of course, don't forget to delete any user created GDI objects.

[Michael Mattias]

All SDK style, but I never had any luck working with a DC until AFTER WM_INITDIALOG

You might want to just create that control at some arbitrary size, and post yourself a private message as the last step of WM_INITDIALOG.

Then when you get that private message, do all the GetDc and text measuring stuff and resize the control at that time. It's fast enough no one will notice.

It's a thought.

[BOB MECHLER]

Some code I use for self sizing label. You'll have to refer to win32.hlp for the parameters.
PB 7.04 and up
V_COL# and V_ROW# are calculated elsewhere and hFontCap is a 10 pt Ms Sans Serif font. All variables with no type identifier are long.

  hDC = GetDC(hdlg)
  hfont = SelectObject(hDC&,hFontCap)
  GetTextExtentPoint32 hDC, BYVAL STRPTR(V_CAPTION$), LEN(V_CAPTION$), lpSize
  SelectObject hDC, hFont
  ReleaseDC hdlg, hDC
  WdPix = lpSize.cx + 6
  HtPix = lpSize.cy + 1
  DIALOG PIXELS hdlg, WdPix, HtPix TO UNITS WdPix, HtPix
  V_CAPTIONl# = WdPix
  V_LBSTYLE& = %SS_LEFT OR %SS_NOPREFIX OR %SS_NOTIFY: V_XLBSTYLE& = %WS_EX_LEFT
  CONTROL ADD LABEL, hDlg&, V_CAPTIONid% ,V_CAPTION$, V_COL#, V_ROW# + 1, V_CAPTIONl#, V_CAPTIONh#,V_LBSTYLE&,V_XLBSTYLE&
  CONTROL SEND hDlg, V_CAPTIONid%,%WM_SETFONT, hFontCap, %True

BOB MECHLER

[Charles Dietz]

Bern, I think the code below does what you were wanting... beginning the textbox just behind the label, with no spaces. Hope this helps.

#COMPILE EXE
#DIM ALL
#INCLUDE "WIN32API.INC"
#INCLUDE "debug.inc"

%IDD_DIALOG1   = 101
%IDC_TEXTBOX1  = 1001

FUNCTION PBMAIN()
   ShowDIALOG1 %HWND_DESKTOP
END FUNCTION

CALLBACK FUNCTION ShowDIALOG1Proc()
   SELECT CASE CBMSG
      CASE %WM_COMMAND
         SELECT CASE CBCTL
            CASE %IDOK
               IF CB.CTLMSG = %BN_CLICKED OR CB.CTLMSG = 1 THEN
                  DIALOG END CB.HNDL, 1
               END IF
            CASE %IDCANCEL
               IF CB.CTLMSG = %BN_CLICKED OR CB.CTLMSG = 1 THEN
                  DIALOG END CB.HNDL, 0
               END IF
         END SELECT
   END SELECT
END FUNCTION

FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG
   LOCAL lRslt, hdc, sLen, nWidth, hFont AS LONG
   LOCAL hDlg AS DWORD
   LOCAL sTemp AS STRING, sLabel AS STRING
   LOCAL lRect AS RECT
   LOCAL I AS LONG, J AS LONG
   
   I = 1
   
   DIALOG NEW hParent, "Test", , , 255, 47 + I * 20, %WS_POPUP OR _
   					%WS_DLGFRAME OR %WS_CAPTION OR %WS_SYSMENU OR %WS_MINIMIZEBOX OR _
   					%WS_VISIBLE OR %DS_CENTER OR %DS_3DLOOK OR %DS_NOFAILCREATE OR _
   					%DS_SETFONT, %WS_EX_WINDOWEDGE OR %WS_EX_LEFT OR %WS_EX_LTRREADING OR _
   					%WS_EX_RIGHTSCROLLBAR, TO hDlg
   
   sLabel = "My New Description:"
   hdc = GetDC(hDlg): sLen = LEN(sLabel)
   DIALOG SEND hDlg, %WM_GETFONT, 0, 0 TO hFont
   SelectObject hdc, hFont
   DrawTextEx BYVAL hdc, BYVAL STRPTR(sLabel), sLen, lRect, %DT_CALCRECT, BYVAL 0
   ReleaseDC hDlg, hdc
   DIALOG PIXELS hDlg, lRect.nRight, lRect.nLeft TO UNITS lRect.nRight, lRect.nLeft
   nWidth = lRect.nRight - lRect.nLeft
     
   CONTROL ADD LABEL, hDlg, -1, sLabel, 5, 5, nWidth + 1, 13, %WS_CHILD _
   						 OR %WS_VISIBLE, %WS_EX_LEFT OR %WS_EX_LTRREADING
   CONTROL ADD TEXTBOX, hDlg, %IDC_TEXTBOX1, "", 5 + nWidth + 1, 4, 235 - lRect.nRight, 13
   
   I = 10 + I * 20
   CONTROL ADD BUTTON, hDlg, %IDOK, "&OK", 10, I, 70, 25
   CONTROL ADD BUTTON, hDlg, %IDCANCEL, "&Cancel", 180, I, 65, 25
   
   DIALOG SHOW MODAL hDlg, CALL ShowDIALOG1Proc TO lRslt
   
   FUNCTION = lRslt
END FUNCTION

[colin glenn]

All SDK style, but I never had any luck working with a DC until AFTER WM_INITDIALOG

Like perhaps with WM_SIZE set a static variable to indicate you set the size, or better yet, use one of the USER variables available with the control itself.

[Barry Erick]

I simply do it this way: if the Label is to the left of the text box, I use RIGHT justify and make sure the background is the same color as the dialog background. If on the right side, i use LEFT justify. If above or below, CENTER justify.

[Michael Mattias]

>Like perhaps with WM_SIZE set a static variable to indicate you set the size

More like, until that window is first shown (After WM_INITDIALOG), operations with GetDC(hWnd) have been flaky.

I know the sizes of controls stuff works funny until then. This usually comes up when create a resizeable screen. I have a function I will call like "Main_RelocateControls", and that NEVER works until AFTER WM_INITDIALOG or WM_CREATE. (that gets and uses the ClientRect of the hWnd and that RECT is NEVER correct on WM_INITDIALOG/WM_CREATE).

When I create resizeable screens, I usually don't bother initially creating all the controls to fit or even be in the right place, because I can always call the "relocater" function which I have to have to call on WM_SIZE anyway.

Then again, it could be I just coded it wrong the very first time I did it many years ago, then fixed the problem when I recoded it (more carefully?) for the processing of the private message, and just never changed how I did it because "it works now."

MCM

[Gösta H. Lovgren-2]

Or, if you were a Trial and Error Dummy (watch me make pointy finger and bend wrist inward maximally), you could create a theoretically long string and see how many units/pixels a label needs to hold it. (Will probably take several/many/lots F5's), then use that number of units when creating the final code. (As a "genera"l rule I use 4.5 per character. Seems to work most of the time, depending on font and size, ...)

Kinda crude but Skinning cats yadayada ....

======================================
"Not only is there no God,
but try finding a plumber on Sunday."
Woody Allen (1935-)
======================================

[Cliff Nichols]

Have not had a chance to research (and always wondered), but no time to do it myself at the moment, my hazy memory (and a quick search) turned up what may be the answer.

try a search on "GetTextExtentPoint32" and I will BET you will get PLENTY of info

[Bern Ertl]

I found a solution and it doesn't matter if I set the size in the dialog creation or in the callback after initialization:

#COMPILE EXE
#DIM ALL

'--------------------------------------------------------------------------------
'   ** Includes **
'--------------------------------------------------------------------------------
#IF NOT %DEF(%WINAPI)
	#INCLUDE "WIN32API.INC"
#ENDIF
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
'   ** Constants **
'--------------------------------------------------------------------------------
%IDD_DIALOG1   = 101
%IDC_TEXTBOX1  = 1001
%IDC_LABEL1    = 1002
'--------------------------------------------------------------------------------

FUNCTION GetTextWidth(BYVAL hWnd AS LONG, BYVAL txt AS STRING) AS LONG

	 LOCAL hDc AS LONG, hFont AS LONG, lpSize AS SIZEL

	 hDc = GetDc(hWnd)                                 'get handle for proper device context
		  hFont = SendMessage(hWnd, %WM_GETFONT, 0, 0)  'must select hWnd's font into DC,
		  hFont = SelectObject(hDC, hFont)              'otherwise System font is used..
		  CALL GetTextExtentPoint32(hDc, BYVAL STRPTR(txt), LEN(txt), lpSize)
		  SelectObject hDC, hFont                       'select original font back
	 ReleaseDC hWnd, hDc                               'and release DC

	 'function returns the textwidth + width of left and right borders
	 FUNCTION = lpSize.cx + GetSystemMetrics( %SM_CXEDGE) * 2

END FUNCTION

'--------------------------------------------------------------------------------
'   ** CallBacks **
'--------------------------------------------------------------------------------
CALLBACK FUNCTION ShowDIALOG1Proc()

	LOCAL X AS LONG, Y AS LONG, lWidth AS LONG
	LOCAL sLabel AS STRING

	SELECT CASE AS LONG CB.MSG
		CASE %WM_COMMAND
			SELECT CASE AS LONG CB.CTL
				CASE %IDOK
					IF CB.CTLMSG = %BN_CLICKED OR CB.CTLMSG = 1 THEN
						CONTROL GET TEXT CB.HNDL, %IDC_LABEL1 TO sLabel

						lWidth = GetTextWidth( CB.HNDL, sLabel)

						DIALOG PIXELS CB.HNDL, lWidth, Y TO UNITS lWidth, Y

						CONTROL GET SIZE CB.HNDL, %IDC_LABEL1 TO X, Y
						CONTROL SET SIZE CB.HNDL, %IDC_LABEL1, lWidth, Y

						CONTROL GET LOC CB.HNDL, %IDC_TEXTBOX1 TO X, Y    'Get Y position
						CONTROL SET LOC CB.HNDL, %IDC_TEXTBOX1, lWidth + 10, Y
						CONTROL GET SIZE CB.HNDL, %IDC_TEXTBOX1 TO X, Y   'Get height
						CONTROL SET SIZE CB.HNDL, %IDC_TEXTBOX1, 235 - lWidth, Y

						CONTROL SET TEXT CB.HNDL, %IDC_LABEL1, sLabel     'Refresh display of label
					END IF

				CASE %IDCANCEL
					IF CB.CTLMSG = %BN_CLICKED OR CB.CTLMSG = 1 THEN
						CONTROL GET TEXT CB.HNDL, %IDC_TEXTBOX1 TO sLabel
						CONTROL SET TEXT CB.HNDL, %IDC_LABEL1, sLabel
					END IF
			END SELECT

	END SELECT

END FUNCTION
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
'   ** Dialogs **
'--------------------------------------------------------------------------------
FUNCTION ShowDIALOG1(BYVAL hParent AS DWORD) AS LONG

	LOCAL lResult AS LONG, lWidth AS LONG, Y AS LONG
	LOCAL hDlg AS DWORD
	LOCAL sLabel AS STRING

	DIALOG NEW hParent, "Test", , , 255, 65, %WS_POPUP OR _
						%WS_DLGFRAME OR %WS_CAPTION OR %WS_SYSMENU OR %WS_MINIMIZEBOX OR _
						%WS_VISIBLE OR %DS_CENTER OR %DS_3DLOOK OR %DS_NOFAILCREATE OR _
						%DS_SETFONT, %WS_EX_WINDOWEDGE OR %WS_EX_LEFT OR %WS_EX_LTRREADING OR _
						%WS_EX_RIGHTSCROLLBAR, TO hDlg

	sLabel = "Description:"

	lWidth = GetTextWidth( hDlg, sLabel)
	DIALOG PIXELS hDlg, lWidth, Y TO UNITS lWidth, Y

	'Include %WS_EX_CLIENTEDGE if you want to see the border on the label
	CONTROL ADD LABEL, hDlg, %IDC_LABEL1, sLabel, 5, 5, lWidth, 13, %WS_CHILD _
							 OR %WS_VISIBLE, %WS_EX_LEFT OR %WS_EX_LTRREADING 'OR %WS_EX_CLIENTEDGE

	CONTROL ADD TEXTBOX, hDlg, %IDC_TEXTBOX1, "", lWidth + 10, 4, 235 - lWidth, 13

	CONTROL ADD BUTTON, hDlg, %IDOK, "&Resize", 10, 30, 85, 25
	CONTROL ADD BUTTON, hDlg, %IDCANCEL, "&Change Label", 160, 30, 85, 25

	DIALOG SHOW MODAL hDlg, CALL ShowDIALOG1Proc TO lResult

	FUNCTION = lResult
END FUNCTION
'--------------------------------------------------------------------------------

'--------------------------------------------------------------------------------
FUNCTION PBMAIN()
	ShowDIALOG1 %HWND_DESKTOP
END FUNCTION
'--------------------------------------------------------------------------------