fxruby users - Aug 2008 - is there a memory limitation on fxruby-mswin32 ?

Hi All,

I wonder is there a memory limitation on fxruby-mswin32 ?
I build an application which uses a lot of checkboxes, it seems running
well on Linux...but it crashes on Windows.

Would you please try to run the following code...

========= HERE IS THE CODE =======require ''fox16''
include Fox

class CheckersView < FXMatrix
   def initialize(parent)
     super(parent, 10, :opts => MATRIX_BY_COLUMNS)
     5.times { 10.times {
       FXCheckButton.new(self, '''', :opts =>
LAYOUT_FILL_X|LAYOUT_FILL_Y)
     } }
   end
end

class TestView < FXMainWindow
   def initialize(app)
     super(app, ''Test Memory App'', :opts => DECOR_ALL,
                 :width => 600, :height => 600)

     vframe = FXVerticalFrame.new(self, LAYOUT_FILL)
     FXButton.new(vframe, ''Add'') do |button|
       button.connect(SEL_COMMAND) do
         add_table(@frame, true)
         @frame.parent.layout
         puts "add_table"
       end
     end
     @counter = 1

     FXScrollWindow.new(vframe, LAYOUT_FILL) do |scroll|
       @frame = FXVerticalFrame.new(scroll, LAYOUT_FILL)
       93.times { add_table(@frame) }
     end
   end

   def add_table(table_parent, with_create=false)
     vframe = FXVerticalFrame.new(table_parent)
     label  = FXLabel.new(vframe, @counter.to_s)
     matrix  = FXMatrix.new(vframe, 3, :opts => MATRIX_BY_COLUMNS)
     CheckersView.new(matrix)
     FXVerticalFrame.new(matrix)
     CheckersView.new(matrix)

     vframe.create if with_create
     @counter += 1
   end

   def create
     super
     show(PLACEMENT_SCREEN)
   end
end

FXApp.new do |app|
   TestView.new(app)
   app.create
   app.run
end
========= END OF CODE =======
Here I create 93 rows whose each row has 2 table and each table consists
of 50 checkboxes. At the topmost of window is a button that is intended
to add a new row. The application will crash if the total of rows reach 95.
Sometimes it gives a "[BUG] Segmentation fault" messsage which points
to
FXMatrix''s constructor (kwargs.rb). But sometimes it will silently
hang,
at this moment you can check that the output of "add_table"
isn''t
printed even though the button was clicked.

My Windows spesifications are RubyOneClickInstaller-1.8.26 and lib
FXRuby-1.6.12 which come along with the installer.
I can run the code on Linux, I even can test it with given 150 rows and
it''s still running well. My Linux specifications are Ruby-1.8.5 and
installed gem fxruby-1.6.15.

Any workaround for this issue?


Thanks,

Erdwin

On Aug 10, 2008, at 11:26 PM, Erdwin Lianata wrote:
> I wonder is there a memory limitation on fxruby-mswin32 ?
> I build an application which uses a lot of checkboxes, it seems  
> running
> well on Linux...but it crashes on Windows.
<snip>
> Here I create 93 rows whose each row has 2 table and each table  
> consists
> of 50 checkboxes. At the topmost of window is a button that is  
> intended
> to add a new row. The application will crash if the total of rows  
> reach 95.
> Sometimes it gives a "[BUG] Segmentation fault" messsage which  
> points to
> FXMatrix''s constructor (kwargs.rb). But sometimes it will silently
> hang,
> at this moment you can check that the output of "add_table"
isn''t
> printed even though the button was clicked.
There is no limitation in the FXRuby code, but you may be running into  
some limitation of the Windows OS; see for example this article:

	http://support.microsoft.com/kb/327699

Let''s focus on the add_table() method from your program:

	 def add_table(table_parent, with_create=false)
	   vframe = FXVerticalFrame.new(table_parent)
	   label  = FXLabel.new(vframe, @counter.to_s)
	   matrix  = FXMatrix.new(vframe, 3, :opts => MATRIX_BY_COLUMNS)
	   CheckersView.new(matrix)
	   FXVerticalFrame.new(matrix)
	   CheckersView.new(matrix)

	   vframe.create if with_create
	   @counter += 1
	 end

Each CheckersView uses up 51 windows handles (one for the matrix, plus  
50 more for the checkboxes). In add_table() I see:

	vframe (1) + label (1) + matrix (1) + CheckersView (51) + vertical  
frame (1) + CheckersView (51) = 106

So that makes 106 window handles used per call to add_table(), and if  
we call it 93 times:

	106*93 = 9,858 window handles

which is awfully close to the 10,000 handles limit mentioned in the  
article that I linked to.
> Any workaround for this issue?
I''m having trouble imagining why you''d want 930 checkboxes on
the
screen at the same time; that seems like an awful lot of information  
to present to the user at once. If there''s some way to restructure the
user interface so that you can create some of those checkboxes on  
demand, and show them only when they''re actually needed.

Hope this helps,

Lyle

---
"FXRuby: Create Lean and Mean GUIs with Ruby"
Now available from the Pragmatic Bookshelf!
http://www.pragprog.com/titles/fxruby

Lyle Johnson wrote:
> I''m having trouble imagining why you''d want 930
checkboxes on the screen
> at the same time; that seems like an awful lot of information to present 
> to the user at once. If there''s some way to restructure the user 
> interface so that you can create some of those checkboxes on demand, and 
> show them only when they''re actually needed.
Thanks Lyle, it solves my problem at this moment (though only 18,000 
maximum number of handles is supported by the hotfix). Since I''m not a 
Windows user, I thought that problem was a portability issue of fxruby.

Anyway, I''m actually creating an statistical application that needs a 
set of checkboxes to give user a table-like input (only on/off switch) 
to filter out each computation result. That''s why I need to create a
lot
of checkboxes at the same time, it''s not possible to show only partial 
of them.

I have one more question, is there a way to remove "handle" for a 
widget? Widgets such as label, vertical/horizontal frame, and 
only-display widgets no need to receive a user response (in my app). So 
I can reduce the number of handle.


Thanks,

Erdwin

On Tue, Aug 12, 2008 at 4:11 AM, Erdwin Lianata
<erdwin.lianata at yahoo.com.sg> wrote:
> I have one more question, is there a way to remove "handle" for a
widget?
> Widgets such as label, vertical/horizontal frame, and only-display widgets
> no need to receive a user response (in my app). So I can reduce the number
> of handle.
No. Even windows that are display-only (like labels and frames) always
have an associated window handle.

fxruby-users-bounces at rubyforge.org wrote:
> Lyle Johnson wrote:
>> I''m having trouble imagining why you''d want 930
checkboxes on the
>> screen at the same time; that seems like an awful lot of information
>> to present to the user at once. If there''s some way to
restructure
>> the user interface so that you can create some of those checkboxes on
>> demand, and show them only when they''re actually needed.
> 
> Thanks Lyle, it solves my problem at this moment (though only 18,000
> maximum number of handles is supported by the hotfix). Since I''m
not
> a Windows user, I thought that problem was a portability issue of
> fxruby.   
> 
> Anyway, I''m actually creating an statistical application that
needs a
> set of checkboxes to give user a table-like input (only on/off
> switch) to filter out each computation result. That''s why I need
to
> create a lot of checkboxes at the same time, it''s not possible to
> show only partial of them.    
Hi,

Instead of creating so many checkboxes, you could maybe use an FXTable
object, and process the clicks inside cells in order to toggle an icon
inside. That''s a little more work, but you shouldn''t have any
limitation
in this case. That''s what I do in my framework.

Regards,

Philippe Lang