pachli-android/core/navigation
Nik Clayton 00a2cd32d3
change: Implement more of FiltersRepository (#816)
The previous code had a number of problems, including:

- Calls to the filters API were scattered through UI and viewmodel code.
- Repeated places where the differences between the v1 and v2 Mastodon
filters API had to be handled.
- UI and viewmodel code using the network filter classes, which tied
them to the API implementation.
- Error handling was inconsistent.

Fix this.

## FiltersRepository

- All filter management now goes through `FiltersRepository`.
- `FiltersRepository` exposes the current set of filters as a
`StateFlow`, and automatically updates it when the current server
changes or any changes to filters are made. This makes
`FilterChangeEvent` obsolete.
- Other operations on filters are exposed through `FiltersRepository` as
functions for viewmodels to call.
- Within the bulk of the app a new `Filter` class is used to represent a
filter; handling the differences between the v1 and v2 APIs is
encapsulated in `FiltersRepository`.
- Represent errors when handling filters as subclasses of `PachliError`,
and use `Result<V, E>` throughout, including using `ApiResult` for all
filter API results.
- Provide different types to distinguish between new-and-unsaved
filters, new-and-unsaved keywords, and in-progress edits to filters.

## Editing filters

- Accept an optional complete filter, or filter ID, as parameters in the
intent that launches `EditFilterActivity`. Pass those to the viewmodel
using assisted injection so the viewmodel has the info immediately.
- In the viewmodel use a new `FilterViewData` type to model the data
used to display and edit the filter.
- Start using the UiSuccess/UiError model. Refrain from cutting over to
full the action implementation as that would be a much larger change.
- Use `FiltersRepository` instead of making any API calls directly.

## Listing filters

- Use `FiltersRepository` instead of making any API calls directly.

## EventHub

- Remove `FilterChangedEvent`. Update everywhere that used it to use the
flow from `FiltersRepository`.
2024-07-14 15:36:52 +02:00
..
src/main change: Implement more of FiltersRepository (#816) 2024-07-14 15:36:52 +02:00
README.md refactor: Rename `StatusListActivity` to `TimelineActivity` (#577) 2024-03-30 23:48:04 +01:00
build.gradle.kts change: Implement more of FiltersRepository (#816) 2024-07-14 15:36:52 +02:00
lint-baseline.xml refactor: Break navigation dependency cycles with :core:navigation (#305) 2023-12-07 18:36:00 +01:00

README.md

:core:navigation

package app.pachli.core.navigation

Intents for starting activities to break circular dependencies.

A common approach for surfacing type-safe (ish) intents to start activities is for the activity-to-be-launched to provide a method in a companion object that returns the relevant intent, possibly taking additional parameters that will be included in the intent as extras.

E.g., if A wants to start B, B provides the method that returns the intent.

This introduces a dependency between A and B.

This is worse if B also wants to start A.

For example, if A is TimelineActivity and B isViewThreadActivity. The user might click a status in TimelineActivity to view the thread, starting ViewThreadActivity. But from the thread they might click a hashtag to view the list of statuses with that hashtag. Now TimelineActivity and ViewThreadActivity have a circular dependency.

Even if that doesn't happen the dependency means that any changes to B will trigger a rebuild of A, even if the changes to B are not relevant.

This package contains Intent subclasses that should be used instead. The quadrant plugin is used to generate constants that can be used to launch activities by name instead of by class, breaking the dependency chain.

If the activity's intent requires specific extras those are passed via the constructor, with companion object methods to extract them from the intent.

Using the intent classes from this package is enforced by a lint IntentDetector which will warn if any intents are created using a class literal.