FiveTech Software tech support forums

Hi,

Is it still required to destroy Font object to release memory occupied by it ? I am using Jun-2005 build.

TIA
Milan.

Yes for fonts created by yourself and used "on the fly", ie. not assigned to any controls.

EMG

Does this mean if the program is terminated with oWnd:end() that the FONT is still occupying the memory?
Is there a function to know which Fonts one have ceated?

Thanks in advance
Otto

Otto,

In this thread we explain how to check all created GDI objects:
viewtopic.php?f=3&t=15935&start=0&hilit=gdi+resources

Antonio,
I don’t understand exactly when a FONT has to be released.
If I look into the new tribbon classe I see that ::oFont is created.
How is this Font released?

If I use for example:
Func test(oFont)
Local oFont1
oFont1:=oFont
return nil

Do I have 2 fonts and must I release oFont1?
Thanks in advance
Otto

Otto,

If you mean this font in Class TRibbonBar:

Code: Select all  Expand view

   if ::oFont == nil
      ::oFont := TFont():New()
      ::oFont:hFont := GetStockObject( DEFAULT_GUI_FONT )
   endif
 

there is no need to destroy it as it uses a Windows own hFont.

If you create a font using:

Code: Select all  Expand view

DEFINE FONT oFont NAME ... SIZE ..., ...
 

then after is used by an object (window, dialog, control, printer) you have to destroy it yourself:

Code: Select all  Expand view

oFont:End()
 

Fonts reuse their hFont handles to reduce GDI memory consume, using a counter which gets incremented when the font is assigned to an object and decremented when the object is End()ed. But when we do oFont:End() then the counter is decreased to zero and then it is really destroyed

Hello Antonio,

Thank you for your help.

I use 2 methods to paint my booking plan:
paint + paintChart
Depending on some conditions I use
::paintChartFont := ::oFont
Or
::paintChartFont := ::planFont

Does this assignment always create a new font ?
Thanks in advance
Otto

Code: Select all  Expand view

METHOD paint()

   do while .not. EOF()
      IF PLAN_DB->jahrgang4 = "MELD"
         ::paintChartFont := ::oFont
       else
         ::paintChartFont := ::planFont
       ENDIF

      ::PaintChart(  )
      skip

   ENDDO

return nil
//----------------------------------------------------------------------------//

METHOD PaintChart()
   hOldFont := SelectObject( ::oWnd:hDC, ::paintChartFont:hFont )

   DrawText( ::oWnd:hDC, cChartCaption,{ nCurRow - 6 ,;
      StartPX + nTemp ,;
      nCurRow + ::nRowHeight ,;
      StartPX + nDurationPX + ::nColWidth/2 - 2  }, nStyle  )

   SelectObject(  ::oWnd:hDC, hOldFont )
   DeleteObject( hOldFont )
return nil

//----------------------------------------------------------------------------//
 

Otto,

No, you are just creating an alias for the same font object.

To create a copy of an object:

oNew := oClone( oObject )

James

James,
Thank you James for explaining this to me.
Best regards,
Otto

James, Otto,

Please be aware that oClone() should not be used with Windows handles as those can't be "cloned"

Antonio,

Thanks for pointing that out. Very important!

James