Nested gallery will not collapse when not selected (not visible)

[AmyF]

I feel like I'd solved this already.  I had an app, there was something fundamentally wrong with it as no patches of columns from the gallery would work.  I could patch a literal value, but was unable to patch any of the gallery fields which absolutely had data in them.

When I'd click a button on the page with the gallery to do the patch, if I examined any of the fields I was attempting to patch they were null within that gallery and I know this because I put them in a variable and they were null.  So again, it would patch a literal value like "Hello there" to say a single line text field but it would not patch txtInputNotes  which was the field name in the gallery.  Nor txtInputNotes.Text  nor txtInputNotes.Value.   I tried every way possible but it wouldn't text anything but a literal in quotes.

I cut it down so bare that I finally gave up and thought I'd have to build a new gallery.  duplicated the page, built new gallery from scratch (well it's a groupby situation so I built 2).   I don't know if I can patch yet, just trying to finish the gallery to the point I had it before.  Now this new gallery is not hiding the nested gallery items when the parent is not selected.  I'm trying EVERYTHING.  I checked a video to recall if I did something wrong and in the video the child gallery was hidden simply by putting an IsSelected in the Visible property.     Sadly this isn't working for me either.   I don't want to pound on this for days and days if there's something fundamentally wrong with this new set of galleries I'm creating.  And since I never give up, I will waste days and days until I finally just give up and try again.

ANY suggestions are welcome I'm at wits end and working on my vacation time.   very sad.

[Chris-D]

You don't need an UnGroup() to reference controls in the gallery. 

If you notice, I don't prefix the control name with the gallery name. My gallery is Gallery1, Gallery1 has InputNotes text input control. I'm not getting the value with Gallery1.InputNotes.Text, this won't work. I'm using ForAll() to make a list of ALL the gallery controls and their ID's, and the doing a LookUp() on this list. 

[AmyF]

When I use

Collect(getAllKids,{cID: ThisItem.ID});

I get the ID in that collection and I'm able to iterate through those to do LookUps.

I've tried putting both the Status field in that record and the notes field (adding both of those values) but when I went to do the loop and patch, the  cID column had the ID numbers of the rows I needed to patch but both other fields are null)  the values in the nested gallery seem to only exist there and are not addressable or something.

[Chris-D]

There's a better way to do this. I've written a demo with a collection that tracks the changes in the form. When the text input is changed, this is reflected into a collection. The collection contains the ID and the Text. 

The OnChange code of the text input:

// See if we already have a change record for this item
If( IsBlank( LookUp( GalleryChanges, ID = ThisItem.ID)),

    // If we don't, create a record
    Collect( GalleryChanges, {
        ID: ThisItem.ID,
        Note: Self.Text
    }),

    // If a record exists, update it with this change
    Patch( GalleryChanges,
        LookUp( GalleryChanges, ID = ThisItem.ID), 
        {
            Note: Self.Text
        }
    );
)

Remember to clear the changes collection on page visible. 

Once you've got this, you can use the fast Patch() method to merge the changes:

Patch( MyDataSource, GalleryChanges);

[AmyF]

I appreciate your help,

Yeah I tried that and it didn't work for me.  in my scenario Self.Text is null.

I have no doubt something like this will work with a regular nested gallery.  The problem lies in a GroupBy nested gallery where the data source of the nested gallery is something like   ThisItem.DATA   where DATA comes from the GroupBy command.  (it's the final parameter).  So unless your tests are using GroupBy you will not re-create my scenario.  

Also,  In what limited experience I have with the Patch(DataSource, Collection) is a DOG in terms of processing.  It touches every field of every row of the datasource and on sufficiently large datasources it is unbearably slow.

[Chris-D]

ok so here are some facts. Your gallery does not know if it's nested or not. It doesn't know if it's data source is grouped or not. It's simply a list of records. There is no difference between a 'regular' nested gallery and a 'grouped' nested gallery. There is only 'gallery'. Self.Text on an input control is never wrong. 

To prove this, here's my demo but now I have 2 galleries and I'm grouping by date in the same way you are. 

I couldn't get the nested look up to work (although if I spent more time I see no reason why I couldn't), but without any modification, the changes table still works, using the exact same OnChange code as above. I actually copy & pasted it from this thread to make sure it was exactly as I'd quoted. 

From my experience, Patch( DataSource, Collection) is huuuuuuugely faster. I've only had data sets of <10k rows though, maybe it slows down with larger data sets but to bulk add 100 or so records is a couple of seconds rather than a couple of minutes using Patch( ForAll()).

Regardless, Patch( ForAll()) should still work for you if you prefer it. 

Not sure why you're still getting null values. Suggest you use the OnChange code above and put a table in to see what that's producing?

[AmyF]

Chris, I appreciate all your help, but a GroupBy nested gallery is different than a regular nested gallery.  If you've never done one and then patched from it you won't know what I'm talking about.  The values are null beyond the gallery.  When I attempt to collect them along with the ID they are null.  

If you are doing regular nested galleries, what are your two data sources?  Are they a collection?  The same collection?  

With a GroupBy the nested gallery is in a structure that you name on the GroupBy command.  GroupBy( Table, ColumnName1 [, ColumnName2, ... ], GroupColumnName )  

The GroupColumnName field names the nested data source.  So you are not dealing directly with a datasource you are dealing with an obscured datasource.  So if your GroupColumnName is "DATA"  then your datasource on the nested gallery is ThisItem.DATA    which doesn't really exist.   How many regular nested galleries have you dealt with having this data source.

If you've never done it with a GroupBy, then you've never done it.  I am not able to find ONE example of a groupby nested editable grid gallery.  Not one.    

Just for fun, let's say there is zero difference between the two types of nested galleries.  Then you should be able to take any nested gallery that isn't done using a GroupBy and convert it and it should work fine, right?

Can you find me one example that 1. Uses GroupBy and also patches from changes made to the nested gallery.   All I need is one working example.   But I find none.

I've asked on the GroupBy videos on YouTube... nothing that also patches.  You get GroupBy nested galleries that don't have an example using patch or you get regular nested galleries, which I have no problem patching from.

So in my limited experience it does matter.   

If what you say is true, why haven't you shown me an example that actually uses GroupBy?   Just one is all I need.

I'm beginning to think it's not possible but that makes no sense.  But it also makes no sense that I cannot find one example of this in action.  Not in the doc, the forums nor youTube.  And when I tried to collect one of the other fields along with the ID it is null.  they all are.  If you can do a GroupBy and get around that null problem and actually patch from the nested gallery, I will sing your praises on high, I will buy you a beer or five...   In all my searching and forum interaction.  Not one true example.   I wonder why?

[Chris-D · Accepted solution]

Hi Amy, thanks for the reply I thought you might have given up 😉

I'm aware of how GroupBy() works and am very familiar with nested data structures but thanks for the explanation.

In my example above...

Gallery1.Items:

GroupBy(
    Sort(
        AddColumns( 
            Penguins,
            "CountDate", DateValue( $"{Coalesce(day, 1)}/{Coalesce(month, 1)}/{year}"),
            "CountDateText", $"{Left( Text( Coalesce(month, 1), "mmmm"), 3)}-{year}"
        ),
        CountDate, SortOrder.Descending
    ),
    "CountDateText",
    "Data"
)

Gallery2.Items (nested inside Gallery1) exactly as you say:

ThisItem.Data

InputNotes.OnChange inside Gallery2 (my text input control):

// See if we already have a change record for this item
If( IsBlank( LookUp( GalleryChanges, ID = ThisItem.ID)),

    // If we don't, create a record
    Collect( GalleryChanges, {
        ID: ThisItem.ID,
        Note: Self.Text
    }),

    // If a record exists, update it with this change
    Patch( GalleryChanges,
        LookUp( GalleryChanges, ID = ThisItem.ID), 
        {
            Note: Self.Text
        }
    );
)

This produces the list of changes displayed in my data table above. You should simply be able to patch from this as I said:

Patch( DataSource, CollectionOfChanges);

Just for fun, I added a button and did (almost) exactly this and hey presto, my list is patched. 

I would suggest that you can't find an example because you are looking for a 'GroupBy gallery' which isn't a thing. 

Anyway, since I have provided a working example you can PM me to arrange the beers 😉 

[AmyF]

Chris!!!   Let's make arrangements for beer!!!  Thank you for sticking with me.  I was attempting to collect ThisItem.Status.Selected.Value,  that didn't work but when I changed it to Self.Status.Selected.Value of course it didn't work either but when I finally landed on Self.Selected.Value it worked.   I still don't understand why I can get the row id using ThisItem  but need Self for the data .... is it that ThisItem refers to the row and Self refers to the cell itself?     This is the problem I've been having all along.  I need to understand this better but you sir, who did not give up on me, lead me to the answer even when I couldn't see it so #1 THANK YOU SO MUCH.  #2 You should make a video, I can tell by the thumbs up on my questions on youtube that it would get a lot of hits.  Anyway I'm accepting your last as the solution because you drilled it into my head such that i could translate it to my code....  eternally grateful and owe you BEER!!!

[Chris-D]

No problem, glad you got it working 🙂 

ThisItem - inside a gallery, this is the record for that row. 

ThisItem.Column - the value of the column for that row.

Self - on a control is a reference to itself. 

Self.Selected - on a control like a dropdown is the current selected item

Self.Selected.Value - on a dropdown created from a list of single values is the value of that item

Does that make sense? 

YouTube? No thanks haha! 

[AmyF]

Well again, sir, thanks.  I do have one more followup question, more of an algorithm one.  Originally one one of my other screens, I simply collected the IDs, then I did a distinct on them because I knew if it was in there that I just had to force a status of "Approved" or whatever.   

Now, I've got 2 possible fields that may be updated.  So now I end up with a list of IDs and changes that look like this:

cID      cStatus     cNotes  cTimestamp    (there will be more fields ultimately)  and the records look like this:

 2          Approved                                   9/12/2023 11:05:33

 2                          These are my notes    9/12/2023 11:05: 42

 2           <blank>                                     9/12/2023 11:05:47

 2          Waitlisted                                    9/12/2023 11:05:51         

This series of changes shows a change to status from blank to Approved

a change in notes from blank to "These are my notes"

a change in Status from Approved to Blank   (maybe a mistake)

a change in Status from blank to "Waitlisted"

What I really want is the ending state of both of these fields prior to hitting the button that performs the patch.

Can you suggest a scheme for collecting this information and refining it?   I didn't think this far since I was blocked with the other problem.  So I'm just wondering if you have any suggestions for a "best practice" for collecting this data and executing it?   I need to loop through it because the changes are relatively small and the data set is very large and wide and the Patch(myDataSource, myCollection)  is way too "expensive" and seems to touch every record in the datasource whether changed or not, but truly shouldn't and also when I tested this before... even though I was patching just a few things, each record had a new Modified date.

Either I'm doing something wrong (what are the odds?) or that is the behavior and it really isn't a good choice for large data sets?   

If you'd like me to start a new thread, I'm happy to.  wanna get you your kudos.   But any suggestions in that regard would be helpful   -- do you know of a source for "best practices" that might involve this?   

I don't want to dry your well, so much beer IS available if needed    😄