[lazarus] TListView Sorting
Hi, I have a TListView in Report style. I would like to have the user click on the column to sort by that column. I set the TListView.SortType property to no avail. How do I enable sorting? Thanks Charl -- I love deadlines. I especially love the whooshing sound they make as they fly by. - Douglas Adams
Re: [lazarus] TListview sorting
Oops, didn't see that thread. Will quickly give it a read... G. On 2/28/06, A.J. Venter [EMAIL PROTECTED] wrote: On Tuesday 28 February 2006 10:35, Graeme Geldenhuys wrote: Hi, Has TListview sorting been implemented?. I set the SortType and implemented the OnCompare event, but can't seem to get it working. My workaround is to place all TListItems in a TStringList, call the Sort on the stringlist, and replace all object back into the TListItem. Ugly, but at least it works! :-) I asked the same question last week, and apparently it is not due to widget-level issues, anyway, the solution in my case was to use tgrid (tdrawgrid in my case), with a lot of help from Jesus Reyes on the conversion. Ciao A.J. -- 80% Of a hardware engineer's job is application of the uncertainty principle. 80% of a software engineer's job is pretending this isn't so. A.J. Venter Chief Software Architect OpenLab International http://www.getopenlab.com | +27 82 726 5103 (South Africa) http://www.silentcoder.co.za| +55 118 162 2079 (Brazil) _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] TListview sorting
On Tuesday 28 February 2006 12:45, Graeme Geldenhuys wrote: Hi AJ, I might be to late for you, but this is how I did my sorting in a TListview. It doesn't need to clear the Listview while sorting. You might need to reset the .Selected though. This code goes into the ColumnClick event of the TListview: Thanks for this, though indeed it won´t help me now. Having USED a grid and seen the power of using cell-draw events to display rather than maintaining a list (instant speed increases all around - and BIG NOTICEABLE ones) I am certainly not going back, not while my program needs to handle an average of 12000 entries per session. That said, I haven´t studied your code in detail but the thought occurs to me that nearly every listview sort tutorial for delphi uses an assignment to the customsort event, just about nobody seems to use built-in sorts so perhaps the easiest way to get more compatible is simple to export the right properties from the LCL to ALLOW people to assign a customsort method - which would of course still have to be written by the user. This won´t implement tlistview.sort (for which mind you, your code may be a good start if you feel like working out how to make it a patch) but it WILL allow all those customsort based projects to work on lazarus. Thoughts ? A.J. -- 80% Of a hardware engineer's job is application of the uncertainty principle. 80% of a software engineer's job is pretending this isn't so. A.J. Venter Chief Software Architect OpenLab International http://www.getopenlab.com | +27 82 726 5103 (South Africa) http://www.silentcoder.co.za| +55 118 162 2079 (Brazil) _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
Re: [lazarus] TListview sorting
Have you got a screenshot of you application now, using the Grid? What grid are you using, TStringGrid? I once maintained a app that had a very complex screen using 4 TStringGrids and it looked and worked beautifully. To explain the code a supplied. It actually uses the TStringList Sort method to do the sorting. It adds the references to the TListItems and the correct text from the Listview (depending on what column header was clicked) to the stringlist. It then calls the stringlist sort method.I then run through the StringList assigning the stored TListItems back to the TListView. Simple but effective! ;-) The code is generic enough, to allow you to do a copy/paste into the ColumnClick event. I like your idea of just surfacing the Sort property of the TListview without implementation, so the user can implement there own sorting algorithm. Regards, - Graeme - On 2/28/06, A.J. Venter [EMAIL PROTECTED] wrote: On Tuesday 28 February 2006 12:45, Graeme Geldenhuys wrote: Hi AJ, I might be to late for you, but this is how I did my sorting in a TListview. It doesn't need to clear the Listview while sorting. You might need to reset the .Selected though. This code goes into the ColumnClick event of the TListview: Thanks for this, though indeed it won´t help me now. Having USED a grid and seen the power of using cell-draw events to display rather than maintaining a list (instant speed increases all around - and BIG NOTICEABLE ones) I am certainly not going back, not while my program needs to handle an average of 12000 entries per session. That said, I haven´t studied your code in detail but the thought occurs to me that nearly every listview sort tutorial for delphi uses an assignment to the customsort event, just about nobody seems to use built-in sorts so perhaps the easiest way to get more compatible is simple to export the right properties from the LCL to ALLOW people to assign a customsort method - which would of course still have to be written by the user. This won´t implement tlistview.sort (for which mind you, your code may be a good start if you feel like working out how to make it a patch) but it WILL allow all those customsort based projects to work on lazarus. Thoughts ? _ To unsubscribe: mail [EMAIL PROTECTED] with unsubscribe as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
