form with lots controls takes long time to load

[zismad]

Hi all,
i need a 26 rows by 8 colums check boxes table.
i get the number of rows from a data base so i prefere to create the check boxes at run time.

the thing is it takes something like 10 seconds on my powerful computer to draw them all.
is there a better way to do it ?
the code :

while (row_num2<26)
{ 
for (int chk_cntr = 0; chk_cntr < 8; chk_cntr++)
    {
     chkBox2[chk_cntr + 8 * row_num2] = new CheckBox();
     chkBox2[chk_cntr + 8 * row_num2].Name = "2_" + (chk_cntr + 8 * row_num2).ToString();
     tableLayout2.Controls.Add(chkBox2[chk_cntr + 8 * row_num2], chk_cntr + 2, row_num2 + 1);
    }
       row_num2++;
}

[Ketsuekiame]

Drawing 208 check boxes with GDI will be slow, even on fast machines. The UI operates on a single thread (and hence only a single core even on multi-core machines).

Is there any particular reason you need 208 check boxes? I think there's a design problem here. What's is it you're trying to achieve?

[zismad]

thanks for the reply,

i'm building a GUI for controling a block memory in a chip.
this block has 26 8bits addresses, in which the user should configure.
after acquiring the data I parse each 8 bits to a deciman value (0-255) then send it all using the usb driver to the chip.

is there a better way to do it ?

thanks
Zvika

[Ketsuekiame]

Then I would simply ask for a decimal value to begin with. That would reduce your control size to 26 text boxes.

Alternatively, request it in Binary representation and parse that into a decimal. It's pretty much this in reverse.

Another alternative is to have a drop down list/treeview/similar of addresses and 8 check boxes. Select the address you wish to set, then enable the checkboxes. Disable them after the data for that address has been sent/saved. This way you can get and set the values on the same 8 check boxes.

[nick.crane]

If the level of your user is up to it you could use also use Hexadecimal input.
It is often easier to conceptualise the bit paterns in Hex.

[zismad]

thank you again,

i've had those thoughts while designing, but i think the users whould get confused typing 8 bits in textbox (or maybe i'm underestimating them...)

the solution of a drop down is non practical because many of the adresses are corelated and the user has to see them all.

is it possible to put the 26*8 checkboxes on two tabpages and have two threds draw them in paralel ?

anyway thanks for the advices, if you come up with another solution i would love to hear.

thanks,
Zvika

[ddanbe]

Use SuspendLayout.
Make all your checkboxes.
Use ResumeLayout.

On a side note, this snippet might interest you:
http://www.daniweb.com/code/snippet217338.html

[zismad]

thanks a lot for all the help. i went for the textbox solution. much more elegant this way !