Xdialog List Box Scrolling Help

[Jim Chapman]

Hello,

I am trying to come up with a routine to base a newsletter article on but I am running into an issue that I haven't been able to figure out. In an Xdialog list box I want to be able to scroll the list up so the selected item is at the top of the list. See the following sample:

vList =;
%dlg%,

[Keith Hubert]

RE: Xdialog List Box Scrolling Help

Hi Jim,

I am not sure if if this is what you are looking for but if not I have got something else that you may like to try. Have this for the moment, run it in Alpha Sports.

Keith Hubert
Guild Member
London

'Created By :Keith Hubert
'Updated By :Keith Hubert
DIM SHARED a_selected[100] as C
DIM SHARED varC_result as C

auto_list_cities = table.external_record_content_get("customer","Bill_city","Bill_city","unique_key_value()")
temp_count = w_count(auto_list_cities,crlf())
DIM a_cities[temp_count] as c
a_cities.initialize(auto_list_cities)
ok_button_label = "&OK"
cancel_button_label = "&Cancel"
varC_result = ui_dlg_box("Print Report",
{endregion};
%dlg%, "" then
filter = alltrim(cities)
filter = *for_each(x,"bill_city = " + quote(x), filter)
filter = alltrim(filter)
filter = stritran(filter,crlf()," .or. ")
report.preview("Customer List",filter)
end if

[Jim Chapman]

RE: Xdialog List Box Scrolling Help

Hello Keith,

Thanks very much for your neat example. Xdialog is really a wonderful tool!

What I am trying to do is get the list box in Xdialog to scroll. The progressive lookup article I did in the June issue of the newsletter has garnered more feedback for me, that any other article. This technique is quick and easily built. However, it has one glaring weakness; it queries the table everytime a keystoke is entered. On a large table or over a network, this creates an unacceptable time lag. I am trying to revisit this issue for the pages of the newsletter and have gotten most of the pieces to work. However, I do not know how, or if it is possible, to scroll the list box as I want.

I think this is important in a progressive lookup. As the user types in values, they need to be able to see the first current match, to the values they have typed in, and the subsequent 'potential' matches. In other words, if I type in "sm", I want to see the "smiths" and "smyths", not just the first "smith" at the bottom of the list box.

Thanks,

Jim

[Stan Mathews]

RE: Xdialog List Box Scrolling Help

Jim,

You are probably smart enough to figure out how to use this.

If the dialog opens to the last entry in the list and you then begin typing a name higher, alphabetically, the list scrolls to the first name with that letter at the top of the dialog list and the other names beginning with that letter are visible.

I believe this is the result you want, is is doable and viable?

Stan

[Stan Mathews]

RE: Xdialog List Box Scrolling Help

btw, this opens with the last entry visible

'Date Created: 15-Dec-2003 08:20:26 AM
'Last Updated: 15-Dec-2003 08:20:26 AM
'Created By :
'Updated By :
vList =vSelect = left(word(vlist,-1),1)
ui_dlg_box("Testing",

[Jim Chapman]

RE: Xdialog List Box Scrolling Help

Hello Stan,

An interesting approach, I would never have thought of that. This works, but only if the user sequentially enters the correct characters. If they back up or start over, I'm back to the same issue.

I can filter the list and present a 'new' list to the user, which simulates what I want to achieve, but this causes rather slow screen refreshing when dealing with even a rather small table (5000 records or so).

For all I know, this may not be possible with Xdialog in its present form, but I've got to think there is an 'undocumented' command in there somewhere :-)

Thanks for your help Stan,

Jim

[CALocklin]

RE: Xdialog List Box Scrolling Help

Took about 15 minutes but it was a fun challenge. I did it completely with strings but it could also be done with a couple arrays - I'm not sure which would be faster.

(I hope I got the HTML "pre>..."/pre> right!)

vList =  1
        FOR qx = crnt_pos to cnt
            temp_list = temp_list + word(vOrigList,qx,crlf()) + crlf()
        NEXT
        FOR qx = 1 to (crnt_pos-1)
            temp_list = temp_list + word(vOrigList,qx,crlf()) + crlf()
        NEXT
        vlist = temp_list
    END IF
    '=======================
END IF
%code%)

[Stan Mathews]

RE: Xdialog List Box Scrolling Help

Close...

I get an error if the first letter of the entered name (string) is not valid (no name beginning with that letter is in the list). I think it just means crnt_pos needs to be intialized before it is first referenced.

[CALocklin]

RE: Xdialog List Box Scrolling Help

You're right. I forgot to check for "doesn't exist". The original also didn't reset to the top when you back-spaced until the input field was blank. It also created an error if you typed a first letter that was higher than the last value.

Try putting in this new WHILE statement: (Yes, the IF might better be a SELECT statement but it started as an IF and I didn't bother to change it.)

[code]
WHILE qx

[CALocklin]

RE: Xdialog List Box Scrolling Help

I just noticed that I forgot to remove the LastTest variable that I used in my first attempt to fix the problem.

Also, an interesting result: If you type "chu" and exit the dialog, the result will be Chuck (the value from the list rather than the value you typed) but if you type "ed" or any other value that has no match in the list, the returned value will be the value you typed......

Later: I had to take the time to fix the above problem - so here's one solution. (Note: You might WANT to use the unmatched value so the following would only be used if you DON'T want to allow unmatched results.)

IF a_dlg_button = "changed"
    a_dlg_button = ""
    vSelect = vTypeIn
    '=======================
    match = .F.
    qx = 0
    WHILE qx  1
        FOR qx = crnt_pos to cnt
            temp_list = temp_list + word(vOrigList,qx,crlf()) + crlf()
        NEXT
        FOR qx = 1 to (crnt_pos-1)
            temp_list = temp_list + word(vOrigList,qx,crlf()) + crlf()
        NEXT
        vlist = temp_list
    END IF
    '=======================
END IF

Then use this after the xdialog is closed - of course, you can take any action you want based on the results of "match".

IF .not. match
    vSelect = ""
END IF
ui_msg_box( "RESULT", vSelect )

[Jim Chapman]

RE: Xdialog List Box Scrolling Help

Hello Cal,

You got me exited there. I am at fault for not presenting my question better. I am trying to get a progressive lookup to function well in a real world environment. I went down the same road as you. The problem is with a list (generated from a table) the refresh time is too slow.

Here is my actual first try script, which is way to slow. I've attached a database with a 4000 record table and the script. As you can see the refresh time is not good :-)

Thanks,
Jim

t = table.open("customer2")
DIM SHARED vList as C
vndx = t.index_primary_put("Testlist")
vRecNum = vndx.records_get()
vlist = vndx.key_list_get(vRecNum)

t.close()

vlist = *for_each(x,word(x,1)+"{T=.75}"+" "+word(x,2)+space(40)+word(x,-1),vlist)

DIM SHARED vTypeIn as C
DIM SHARED vSelect as C
DIM SHARED varC_result as C
auto_list_vSelect = vList

temp_count = w_count(auto_list_vSelect,crlf())
DELETE a_vSelect
DIM a_vSelect[temp_count] as c
a_vSelect.initialize(auto_list_vSelect)

ok_button_label = "&OK"
cancel_button_label = "&Cancel"
varC_result = ui_dlg_box("Select A Customer", 
{endregion};
%dlg%, 1
		vFeedString = word(vTypeIn,1)+"{T=.75} "+word(vTypeIn,2)
		else
		vFeedString = alltrim(vTypeIn)
	end if 
	vFilter = vFeedString+"*"
	vList2 = filter_string_smatch(vList,vFilter)
	a_vSelect.clear()
	a_vSelect.initialize(vList2)
end if 
profiler_end()
%code%)

if varC_result = "OK" .and. (.not. (vSelect = ""))
	ui_msg_box("Selected",vSelect)
end if

[Jim Chapman]

RE: Xdialog List Box Scrolling Help

Hello,

For any of you following this thread, I have attached a database with my latest script called DumpArrayApproach.
This works against a 4000 record table with a pre-built index. The formatting of the Xdialog list box is not done. Performance is acceptable running locally, but when I increace the table to 24,000 records, the performace degrades significantly. Below is the script. If I could scroll the list box rather than 're-write' the list, I think performance would be much better. Any thought on how to improve the performance?

Thanks,
Jim

profiler_begin()
t = table.open("customer2")
DIM SHARED vList as C
Dim vTypeIn as c
vndx = t.index_primary_put("Test2")
vRecNum = vndx.records_get()
vlist = vndx.key_list_get(vRecNum)
t.close()

dim vArray[vRecNum] as p

vArray.initialize_properties("Name, Recs",vlist)
vDisplay = vArray.dump_properties("Name, Recs")
profiler_end()
ui_dlg_box("Testing",
%dlg%,='"+vTypeIn+"'"
	vDisplay = vArray.dump_properties("Name, Recs",vFilter)
end if 
%code%)

[Jim Chapman]

RE: Xdialog List Box Scrolling Help

For those interested, here is the script profile timing on a 24,000 record table, running on an old 1ghz machine with 768 megs of memory, slow HD:

Script TEMPLATE
Line Tot Time Cnt Source
========================================================
5 0.012543 1 t = table.open("customer")
6 0.000066 1 DIM SHARED vList as C
7 0.000068 1 Dim vTypeIn as c
8 0.000705 1 vndx = t.index_primary_put("Test2")
9 0.027958 1 vRecNum = vndx.records_get()
10 1.003916 1 vlist = vndx.key_list_get(vRecNum)
14 0.000968 1 t.close()
16 0.010792 1 dim vArray[vRecNum] as p
18 1.455741 1 vArray.initialize_properties("Name, Recs",vlist)
19 1.223627 1 vDisplay = vArray.dump_properties("Name, Recs")
========================================================
========================================================

The times do not appear to bad, but each user keystroke will cause a filtered array dump (line 19). Depending on the filter, this could be another 1.2 seconds for the list box to re-write for each keystroke.

[CALocklin]

RE: Xdialog List Box Scrolling Help

I think I may have something but I also think it's time for some sleep - my wife will be getting up in about 2 hours.

[CALocklin]

RE: Xdialog List Box Scrolling Help

Never mind - I was doing basically the same thing with .dump_properties.