At 03:18 2019-01-07, "Fernando D. Bozzo" fdbozzo@gmail.com wrote:
Hi Gene, About this: >"One of the things that Grid is supposedly not for is data entry"
I don't agree.
Neither do I, but I have seen this opinion posted many times over the years. I do not understand it myself, but there it is.
Not sure about the complexity of what you need to do, but if you used FoxPro before VFP, you could remember that before the grid component was the BROWSE command with many parameters that allowed many validations and options for row/column, and that many validations and options where made exactly for that purpose, for data entry. Most of them have no sense for other purpose than data entry.
Yes, but I had a period of time where I was not using xBASE. That was about when the fancy browses had their day. I have looked at BROWSE, and it does not have quite what I want.
One of my first programming challenges was to do a component exactly as you need it to (I'm talking about dBase III+ era), and could do it, but the problem was that performed horribly, too slow to navigate records and columns. I think that you could face the same problem. Do not forget that you have to control each and every aspect of the component, as: - Scrolling left/right controlling start and end columns
I have this scrolling already working in a concept case. It was fairly easy. I grant that this may change when I add more feature. I do not think so though.
- Scrolling top/bottom controlling start and end rows -
Controlling the data you load/unload, because you can't load a millon records in memory, and this forces you to control dinamically the loading of a new bunch of records in the direction you are navigating, and unloading records from the other side -
Yup! It is going to be fun, but I have some ideas.
I am concerned with how the scrollbar works, but I may just come up with my own version that bypasses the issues.
Controlling every key for navigation and other needed purposes - Controlling the visualization of each aspect of your info (think on Autosizing columns, pre-programmed sizes, combination of both, assuring that you show columns correctly and fluently ,etc)
I do not plan to have every feature that Grid has, at least for the start.
I tried to get Grid working when allowing column order to change, and it was horrible.
- More things you may ancounter
Quite possibly.
What I have encountered is trouble with row-level validation. Without that, Grid is NOT what I want.
Obviously I'm thinking in a component that can be used for any table, and not just for one special table, because the programming effort to do this type of component is too high to do it for just one table. Don't know if you already said this because I didn't follow the entire thread, but: What type of validation do you need, and what is the problem you are facing that can't be handled with the grid?
I can not get proper row-level validation working consistently. I have tried and tried and tried. I keep finding cases where it breaks. I deal with a case, and something else breaks. It is very frustrating.
I had quite a lot of trouble to get my test case to work. I had to experiment with events and methods, but once I got it, it worked and did so consistently.
And more importantly: Is really a grid what you need? why can't you use an input form with navigation keys that scrolls data in background?
Because some of the work that needs to be done needs multiple rows visible at once.
[snip]
Sincerely,
Gene Wirchenko
Hi Gene:
I think that I've found what you need. You need to use the Valid event of the grid in combination with the valid of the controls.
Please, read this chapter about grids of the book 1001 things you wanted to know about VFP.
"Grids, the misunderstood controls:"
https://books.google.es/books?id=wKNfTHRNkLAC&pg=PA159&lpg=PA159&...
El mar., 8 ene. 2019 4:27, Gene Wirchenko genew@telus.net escribió:
At 03:18 2019-01-07, "Fernando D. Bozzo" fdbozzo@gmail.com wrote:
Hi Gene, About this: >"One of the things that Grid is supposedly not for is data entry"
I don't agree.
Neither do I, but I have seen this opinion posted many timesover the years. I do not understand it myself, but there it is.
Not sure about the complexity of what you need to do, but if you used FoxPro before VFP, you could remember that before the grid component was the BROWSE command with many parameters that allowed many validations and options for row/column, and that many validations and options where made exactly for that purpose, for data entry. Most of them have no sense for other purpose than data entry.
Yes, but I had a period of time where I was not usingxBASE. That was about when the fancy browses had their day. I have looked at BROWSE, and it does not have quite what I want.
One of my first programming challenges was to do a component exactly as you need it to (I'm talking about dBase III+ era), and could do it, but the problem was that performed horribly, too slow to navigate records and columns. I think that you could face the same problem. Do not forget that you have to control each and every aspect of the component, as: - Scrolling left/right controlling start and end columns
I have this scrolling already working in a concept case. Itwas fairly easy. I grant that this may change when I add more feature. I do not think so though.
- Scrolling top/bottom controlling start and end rows -
Controlling the data you load/unload, because you can't load a millon records in memory, and this forces you to control dinamically the loading of a new bunch of records in the direction you are navigating, and unloading records from the other side -
Yup! It is going to be fun, but I have some ideas. I am concerned with how the scrollbar works, but I may justcome up with my own version that bypasses the issues.
Controlling every key for navigation and other needed purposes - Controlling the visualization of each aspect of your info (think on Autosizing columns, pre-programmed sizes, combination of both, assuring that you show columns correctly and fluently ,etc)
I do not plan to have every feature that Grid has, at least forthe start.
I tried to get Grid working when allowing column order tochange, and it was horrible.
- More things you may ancounter
Quite possibly. What I have encountered is trouble with row-levelvalidation. Without that, Grid is NOT what I want.
Obviously I'm thinking in a component that can be used for any table, and not just for one special table, because the programming effort to do this type of component is too high to do it for just one table. Don't know if you already said this because I didn't follow the entire thread, but: What type of validation do you need, and what is the problem you are facing that can't be handled with the
grid?
I can not get proper row-level validation workingconsistently. I have tried and tried and tried. I keep finding cases where it breaks. I deal with a case, and something else breaks. It is very frustrating.
I had quite a lot of trouble to get my test case to work. Ihad to experiment with events and methods, but once I got it, it worked and did so consistently.
And more importantly: Is really a grid what you need? why can't you use an input form with navigation keys that scrolls data in
background?
Because some of the work that needs to be done needs multiplerows visible at once.
[snip]
Sincerely,
Gene Wirchenko
[excessive quoting removed by server]
On 08/01/2019 03:27, Gene Wirchenko wrote:
<snip>
I can not get proper row-level validation working consistently. I have tried and tried and tried. I keep finding cases where it breaks. I deal with a case, and something else breaks. It is very frustrating.
Maybe you can describe a scenario (with data etc and what you want it to do) where the grid does not work? I'd be interested to see it.
Peter
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Fernando D. Bozzo -
Gene Wirchenko -
Peter Cushing