Suggestion: splitting modules/artifacts

[eonj]

• I have searched existing issues and confirmed this is not a duplicate

This is not a bug report, but an enhancement proposal, so I'm not following the given bug-reporting issue format.

FlexboxLayout is a ViewGroup mainly used for aligning xml-defined views by flexbox. On the other hand, FlexboxLayoutHelper is a LayoutHelper for RecyclerView, which is for displaying large/varying dataset. In most cases, just FlexboxLayout is useful enough. However, the Flexbox library artifact contains both of them.

The problem is that FlexboxLayoutHelper implementation references Android Support Library, and its specific version is linked in the Flexbox library artifact. The application project should check the version of recyclerview-v7 library and match the rest of support modules. (Or, exclude it; but it's quite dangerous in fact).

My suggestion is splitting project modules and resulting library artifacts. Doing this, people who want to use only FlexboxLayout (not FlexboxLayoutHelper) can avoid the recyclerview-v7 linked inside. Making whole-classes artifact still flexbox, we can move the classes into split modules:

• flexbox-common: AlignContent, AlignItems, AlignSelf, FlexContainer, FlexDirection, FlexItem, FlexLine, FlexWrap, JustifyContent
• flexbox-layout: FlexboxLayout (dep: flexbox-common)
• flexbox-layout-manager: FlexboxLayoutManager, FlexboxItemDecoration (dep: flexbox-common)
• flexbox (dep: flexbox-layout, flexbox-layout-manager)

So which module can FlexboxHelper go into? Currently, FlexboxHelper can go nowhere, because it defines behavior of both containers (i.e. FlexboxLayout and FlexboxLayoutManager), and it also contains RecyclerView-related code.

If the modules are to be split, FlexboxHelper code should be split before; first, FlexboxBehavior, one just describing the common behavior; second, FlexboxLayoutManagerHelper, one with the rest code (if needed).

I tried to work with 0.3.1, but it was too hard for me to do that. So I'm making a suggestion issue.

Thanks.

[MGaetan89]

I like this idea, especially because the dependency on RecyclerView adds a lot of methods.
If no one wants to try to do it, I could give it a try, but it would have to wait until the end of the week.

[thagikura]

This needs not a tiny change, but the issue totally makes sense.

I don't have time to work on this anytime soon, if anyone wants to work on this one, it's much appreciated.

[pengood]

@thagikura could you give a ChangeLog with flexbox-layout?

[thagikura]

@pengood it's not relevant to this issue, but https://github.com/google/flexbox-layout/releases has it

[TWiStErRob]

Doing this, people who want to use only FlexboxLayout (not FlexboxLayoutHelper) can avoid the recyclerview-v7 linked inside.

This could be also achieved by changing api to compileOnly for the support libs dependencies of flexbox. (with a limitation that flexbox doesn't reference R stuff AFAIK). We've used provided in Glide for some time and it worked ok. I don't think anyone actually uses the exact version specified by any single AAR library, it's impossible if you have more than one lib pulled in. Most of the time it's just annoying to exclude the support stuff from every single dependency I have because they all publish that dependency. As developers of apps we always want to control which support lib we're using. (It may be just me though, let me know what others think.)

[thagikura]

What @TWiStErRob suggests sound good to me. Released a new version that changed the support lib dependencies to compileOnly.
But I think this issue still worth opening it because it's useful if we can decouple the code that is only used from FlexboxLayoutManager.