A basic grid control (major revision)

srod · Post by **srod** » Sun Sep 11, 2005 11:25 pm

Hi all,

I've been playing around with some intriguing code posted by El-choni some time ago, and have hashed up a basic grid control based on a subclassed ListIconGadget.

I've decided to post the code at what is a very early stage of development in order that more experienced Windows coders might be able to give me some idea as to how far this code can go? Basically, this is approaching the limits of my knowledge of Win API at present and so I don't really know just how far this could be taken, let alone how far I could take it myself.

At the moment, the underlying ListIconGadget is created in the default report view with the default system fonts. Cells can be edited by double clicking. The control seems to behave itself whilst scrolling and whilst the user changes the column widths etc.

As I say, it is early days, but everyone is welcome to use the code in any way.

Regards.

http://www.purecoder.net/purebasic/egrid.zip

srod · Post by **srod** » Tue Sep 13, 2005 12:28 am

Update:

- The grids now seem to work with different fonts and font sizes in that there is no misalignment (at least on my system) with the cell being edited etc. Cells are edited by overlaying a good old string gadget and the alignment of the underlying text and all the margins has caused me a few headaches. It now seems to work on my computer, but I am hoping that others might be able to test this on different Windows setups etc.

-The enter key now acts as it should.

Once I'm happy that the aforementioned alignment issues are well and truly licked, then I will continue to develop the grid.

http://www.purecoder.net/purebasic/egrid.zip

jack · Post by **jack** » Tue Sep 13, 2005 12:56 am

thanks srod

but I think you still have work to do.

srod · Post by **srod** » Tue Sep 13, 2005 7:11 am

The height of the header row is a superficial detail.

Can I ask what you did to end up with 2 edit boxes because I can't seem to recreate it?

Thanks.

**Edit: It seems to occur when the ListIcon gadget is scrolled by using the keyboard and thus avoiding the #WM_VCROLL event in the ListIcon callback. I'll try and fix it tonight. Thanks for reporting, as this one would probably have passed me by!**

LuckyLuke · Post by **LuckyLuke** » Tue Sep 13, 2005 11:17 am

This might help

Code: Select all

Procedure LV_SetHeaderFontStyle(id.l)
  LF.LOGFONT
  hHeader = SendMessage_(id, #LVM_GETHEADER, 0, 0)
  hCurrFont = SendMessage_(hHeader, #WM_GETFONT, 0, 0)
  If GetObject_(hCurrFont, SizeOf(LF), LF) > 0 
    LF\lfWeight = #FW_BOLD    ;#FW_NORMAL
    LF\lfUnderline = #True
    LF\lfItalic = #True    
    LF\lfStrikeOut = #False
    LF\lfHeight = 20
    DeleteObject_(hHeaderFont)
    hHeaderFont = CreateFontIndirect_(LF)
    hOldFont = SelectObject_(hHeader, hHeaderFont)
    SendMessage_(hHeader, #WM_SETFONT, hHeaderFont, #True)

  EndIf

EndProcedure

srod · Post by **srod** » Tue Sep 13, 2005 12:00 pm

Thanks Lucky, I'll give that a whirl after I've fixed the keyboard scrolling prob.

Regards.

srod · Post by **srod** » Wed Sep 14, 2005 11:42 pm

UPDATE:

After many long hours, the scrolling problems seem to be fixed and I cannot find any rendering problems at the moment (although I have only tested this software on Win XP home).

If I am correct and no one finds any bugs with the basic operation of the grid control, then the way is clear to add more of what I would call typical 'grid' functionality.

At the moment, the grid seems to work with any fontsize (I haven't adjusted the header row yet, but that's a minor detail). The grid allows editing in any cell and (fingers crossed) behaves well whilst the grid is scrolled (either using the mouse or the keyboard) or columns are resized etc.

If no bugs are found with the above, I will then set about the following:

tidying up the header row
allowing for dynamic resizing of the entire grid
use of arrow / tab keys to navigate the grid (at the moment they scroll the entire grid without navigating from cell to cell -this was a convenience)
cutting and pasting
etc.

Further ahead I will investigate the possibility of being able to select and highlight a range of cells using click and drag etc. and possibly even embedding other controls within individual cells, but that's a little way off yet.

Anyhow, any feedback/bug reports are greatly appreciated and my thanks to all who are able to test the grids.

Regards.

http://www.purecoder.net/purebasic/egrid.zip

ebs · Post by **ebs** » Thu Sep 15, 2005 2:01 pm

srod,

The updated grid works well, but I have found a problem. Try these steps:

1. Click in a cell to select it.

2. Click in the cell again to start editing it - you will see the caret flashing.

3. Scroll the grid up and down a few times using the mouse wheel, not the scroll bar.

4. I see a number of copies of the selected cell, on top of other cells.
If you click in one of the copies, it goes back to the original cell contents.

Can you (or anyone else) reproduce this behavior, or is it just a problem with my mouse or video drivers?

Regards,
Eric

DoubleDutch · Post by **DoubleDutch** » Thu Sep 15, 2005 4:15 pm

other controls within individual cells, but that's a little way off yet.

srod · Post by **srod** » Thu Sep 15, 2005 6:30 pm

Ebs:

Thanks for the report. Unfortunately, I use a laptop and do not have a mouse wheel. The problem reported is the same that I experienced with the page up/down buttons however, and these were easily fixed. It could simply be a case of rummaging through the WIN API looking for some event I can trap for use of the mousewheel. If I am right, then it is literally 5 lines of code to repair. Unfortunately, however, I won't know if the problem is fixed until someone with a mouse wheel tests the code.

I'll have a look later tonight.

Thanks again.

srod · Post by **srod** » Thu Sep 15, 2005 6:35 pm

Doh!

***Double post!***

Jellybean · Post by **Jellybean** » Thu Sep 15, 2005 7:24 pm

Reproduced text field drawing problems when scolling with scrollwheel.

srod · Post by **srod** » Thu Sep 15, 2005 7:56 pm

***Fix***

Have added code (3 lines!) which I hope fixes the aforementioned problem. I am unable to check whether the fix works because I have no mousewheel.
If someone could be so kind...

http://www.purecoder.net/purebasic/egrid.zip

Thanks.

DoubleDutch · Post by **DoubleDutch** » Thu Sep 15, 2005 10:20 pm

I cannot see any graphic problems with the scroll wheel.

thefool · Post by **thefool** » Thu Sep 15, 2005 10:28 pm

Its fixed! Thanks for this nice code.!