ListPublisher section name transformer not working #355

New Issue

Closed

opened 2025-12-29 15:29:55 +01:00 by adam · 1 comment

adam commented 2025-12-29 15:29:55 +01:00

Owner

Copy Link

Copy Source

Originally created by @joeljfischer on GitHub (Jan 1, 2021).

Hi, I have a .sectionBy clause set up, but it appears that the name transformer isn't working.

listPublisher = CoreStoreDefaults.dataStack.publishList(
    From<Stopwatch>()
        .sectionBy(\.$isStarted, { (sectionName) -> String? in
            if sectionName == "1" {
                return "Running".localized()
            } else {
                return "Stopped".localized()
            }
        })
        .orderBy(.descending(\.$name))
)

Here, $.isStarted a boolean virtual property, but that all appears to be working correctly. I can breakpoint within the .sectionBy closure and it's running and returning the correct string, but 0 or 1 is still appearing as the section header of my list. Do I need to implement titleForHeader / viewForHeaderInSection? It says to do so under the ListMonitor documentation but not the list publisher documentation. If so, what would I access to see my transformed string?

Originally created by @joeljfischer on GitHub (Jan 1, 2021). Hi, I have a `.sectionBy` clause set up, but it appears that the name transformer isn't working. ```swift listPublisher = CoreStoreDefaults.dataStack.publishList( From<Stopwatch>() .sectionBy(\.$isStarted, { (sectionName) -> String? in if sectionName == "1" { return "Running".localized() } else { return "Stopped".localized() } }) .orderBy(.descending(\.$name)) ) ``` Here, `$.isStarted` a boolean virtual property, but that all appears to be working correctly. I can breakpoint within the `.sectionBy` closure and it's running and returning the correct string, but `0` or `1` is still appearing as the section header of my list. Do I need to implement `titleForHeader` / `viewForHeaderInSection`? It says to do so under the `ListMonitor` documentation but not the list publisher documentation. If so, what would I access to see my transformed string?

adam added the enhancement label 2025-12-29 15:29:55 +01:00

adam closed this issue 2025-12-29 15:29:55 +01:00

adam commented 2025-12-29 15:29:56 +01:00

Author

Owner

Copy Link

Copy Source

@JohnEstropia commented on GitHub (Jan 3, 2021):

@joeljfischer The titleForHeader / viewForHeaderInSection for DiffableDataSource adapters currently doesn't support the custom sectionIndex transformers, sorry about that. I'll try to rework the adapters in an update, but for now you have the following options to work around it:

• Subclassing DiffableDataSource.TableViewAdapter or DiffableDataSource.CollectionViewAdapter and override the tableView(_:titleForHeaderInSection:) or collectionView(_:viewForSupplementaryElementOfKind:at:)
• Adding a Field.Virtual property that implements the logic. You can then use that property as the sectionBy key. See the Demo app's example:

Modern.ColorsDemo.dataStack.publishList(
            From<Modern.ColorsDemo.Palette>()
                .sectionBy(\.$colorGroup)
                / /...
        )

        @Field.Virtual(
            "colorGroup",
            customGetter: { object, field in
                
                if let colorGroup = field.primitiveValue {
                    
                    return colorGroup
                }
                let colorGroup: String
                switch object.$hue.value * 359 {
                    
                case 0 ..< 20: colorGroup = "Lower Reds"
                case 20 ..< 57: colorGroup = "Oranges and Browns"
                case 57 ..< 90: colorGroup = "Yellow-Greens"
                case 90 ..< 159: colorGroup = "Greens"
                case 159 ..< 197: colorGroup = "Blue-Greens"
                case 197 ..< 241: colorGroup = "Blues"
                case 241 ..< 297: colorGroup = "Violets"
                case 297 ..< 331: colorGroup = "Magentas"
                default: colorGroup = "Upper Reds"
                }
                field.primitiveValue = colorGroup
                return colorGroup
            }
        )
        var colorGroup: String

@JohnEstropia commented on GitHub (Jan 3, 2021): @joeljfischer The titleForHeader / viewForHeaderInSection for DiffableDataSource adapters currently doesn't support the custom sectionIndex transformers, sorry about that. I'll try to rework the adapters in an update, but for now you have the following options to work around it: - Subclassing `DiffableDataSource.TableViewAdapter` or `DiffableDataSource.CollectionViewAdapter` and override the `tableView(_:titleForHeaderInSection:)` or `collectionView(_:viewForSupplementaryElementOfKind:at:)` - Adding a `Field.Virtual` property that implements the logic. You can then use that property as the `sectionBy` key. See the Demo app's example: ```swift Modern.ColorsDemo.dataStack.publishList( From<Modern.ColorsDemo.Palette>() .sectionBy(\.$colorGroup) / /... ) ``` ```swift @Field.Virtual( "colorGroup", customGetter: { object, field in if let colorGroup = field.primitiveValue { return colorGroup } let colorGroup: String switch object.$hue.value * 359 { case 0 ..< 20: colorGroup = "Lower Reds" case 20 ..< 57: colorGroup = "Oranges and Browns" case 57 ..< 90: colorGroup = "Yellow-Greens" case 90 ..< 159: colorGroup = "Greens" case 159 ..< 197: colorGroup = "Blue-Greens" case 197 ..< 241: colorGroup = "Blues" case 241 ..< 297: colorGroup = "Violets" case 297 ..< 331: colorGroup = "Magentas" default: colorGroup = "Upper Reds" } field.primitiveValue = colorGroup return colorGroup } ) var colorGroup: String ```

Sign in to join this conversation.

No Branch/Tag Specified

Branches Tags

develop

prototype/swift6

master

prototype/concurrency

minIOS13

prototype/containers

transactionSourceTracking

prototype/swiftui

minIOS11

swift5_3

prototype/propertyWrapperFields

prototype/propertyWrappers

prototype/propertyWrapper

Swift5

throwables

prototype/Swift_4_1

prototype/Swift_4_0

prototype/Swift_3_2

prototype/queryBuilders

temp/develop

corestore4_develop

prototype/mainContextToPSC

master_ios_7_to_9

swift_2_3

gh-pages

_corespotlight-test

9.3.0

9.2.0

9.1.0

9.0.0

8.1.0

8.0.1

8.0.0

7.3.1

7.3.0

7.2.0

7.1.0

7.0.4

7.0.3

7.0.2

7.0.1

7.0.0

6.3.2

6.3.1

6.3.0

6.2.1

6.2.0

6.1.0

6.0.0

5.3.1

5.3.0

5.2.0

5.1.1

5.1.0

5.0.0

4.2.4

4.2.3

4.2.2

4.2.1

4.2.0

4.1.4

4.1.3

4.1.1

4.1.0

4.0.5

4.0.4

4.0.3

4.0.2

4.0.1

4.0.0

4.0.0-beta3

4.0.0-beta2

4.0.0-beta

3.1.1

3.1.0

3.0.3

3.0.2

3.0.1

3.0.0

2.1.3

2.1.2

2.1.1

2.1.0

2.0.6

2.0.5

2.0.4

2.0.3

2.0.2

2.0.1

2.0.0

1.6.10

1.6.9

1.6.8

1.6.7

1.6.6

1.6.5

1.6.4

1.6.3

1.6.2

1.6.1

1.6.0

1.5.4

1.5.3

1.5.2

1.5.1

1.5.0

1.4.4

1.4.3

1.4.2

1.4.1

1.4.0

1.3.6

1.3.5

1.3.4

1.3.3

1.3.2

1.3.1

1.3.0

1.2.1

1.2.0

1.0.2

1.0.1

1.0.0

0.2.1

0.2.0

0.1.2

0.1.1

0.1.0

Labels

Clear labels

abandoned

corestore bug

discussion

duplicate

enhancement

fixed

fixed

help wanted

in progress

investigating

ios/compiler bug

irreproducible

looking for workarounds

not a bug

pending

pending docs update

pull-request

Mirrored from GitHub Pull Request

question

regression

user bug

wontfix

No labels enhancement

Milestone

No items

No Milestone

Projects

Clear projects

No projects

Assignees

Clear assignees

adam (Adam Melkus)

No Assignees

1 Participants

Notifications

Subscribe

Due Date

No due date set.

Dependencies

No dependencies set.

Reference: starred/CoreStore#355