flutter_flutter/docs/contributing/Android-API-And-Related-Versions.md
Reid Baker 72c2447307
android_host_app_v2_embedding update dependencies and documentation (#164195)
Related to #149836 

Last of the non api 35 references in flutter/flutter for targetSdk and
compileSdk.
`find . -type f -name "build.gradle" | xargs grep -e "targetSdk" | tr -d
'=' | tr -s ' ' | grep -v flutter\.targetSdkVersion | grep -v
engine/src/flutter/third_party/ | grep -v "targetSdk 35"`
`find . -type f -name "build.gradle" | xargs grep -e "compileSdk" | tr
-d '=' | tr -s ' ' | grep -v flutter\.compileSdkVersion | grep -v
engine/src/flutter/third_party/ | grep -v "compileSdk 35"`

rewrite of https://github.com/flutter/flutter/pull/163622 after this
test was updated to run against a newer version of gradle and agp in
https://github.com/flutter/flutter/pull/163849/files#diff-83b6ad7c016bffbb682664eb65c576a7ebf9c312fc60727c0e0e20f5641cbc2aR462

Android-API-And-Related-Versions.md was updated to reflect that after
further investigation that android is using "=" in their documentation
and that the space syntax is discouraged. Equals is setting a property
and space is the equivalent to a function call like `compileSdk(35)` and
assignment is prefered.

The use of equals for proprty assignment also aligns with
https://docs.gradle.org/current/userguide/migrating_from_groovy_to_kotlin_dsl.html#prepare_your_groovy_scripts

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.
2025-02-27 20:31:08 +00:00

123 lines
3.4 KiB
Markdown

# Android Api and Related versions
Picking the full suite of android versions can be difficult if you are not a full time android developer.
This document is for contributors to understand what versions of common android tooling should be used in the flutter/flutter codebase.
## Overview
**The most important thing is for any test, project, or app to have compatible versions. **
If versions need to be different then a comment explaining why and what is being evaluated should be included.
All chosen versions should pass the minimum versions checks defined in [DependencyVersionChecker](https://github.com/flutter/flutter/blob/main/packages/flutter_tools/gradle/src/main/kotlin/DependencyVersionChecker.kt)
If the versions chosen are not known by [gradle_utils.dart](https://github.com/flutter/flutter/blob/a16c447abcb695b4ca907d59e66dc87f4f7178d3/packages/flutter_tools/lib/src/android/gradle_utils.dart#L63) then update gradle_utils.dart.
## Specifics
### compileSdk
- Must be higher then or equal to `targetSdk`.
- Should be `compileSdk` instead of `compileSdkVersion`.
- Should be the max stable value available in CIPD if not `flutter.compileSdkVersion`.
- Must have a comment if an api level lower than max is chosen intentionally.
```
// OK
android {
compileSdk = flutter.compileSdkVersion
}
```
```
// OK if flutter.compileSdkVersion is not available like in an add to app example.
android {
compileSdk = 35
}
```
```
// NOT OK
android {
compileSdk 28
}
```
### targetSdk
- Must be higher then or equal to `minSdk`.
- Should be `targetSdk` instead of `targetSdkVersion`.
- `targetSdk` takes human level effort to update. This is a design decision by the AGP team.
- `targetSdk` may lag behind compile sdk because of the effort to update.
- If the `targetSdk` version is intentionally different there should be a comment explaining why.
```
// OK
defaultConfig {
targetSdk = flutter.targetSdkVersion
}
```
```
// OK if flutter.compileSdkVersion is not available like in an add to app example.
defaultConfig {
targetSdk = 35
}
```
```
// NOT OK
defaultConfig {
targetSdk 28
}
```
### AGP
AKA `com.android.application`, `com.android.tools.build:gradle` `com.android.library`
- "AGP" version should be the version set in flutter templates or newer.
- If the version is intentionally different there should be a comment explaining why.
```
// OK
dependencies {
classpath "com.android.tools.build:gradle:8.8.1"
}
```
```
// OK
dependencies {
// Testing backwards compatability of feature XYZ
classpath "com.android.tools.build:gradle:7.5.2"
}
```
### gradle
Gradle versions are the least likley to break across minor version updates.
- In new code the "gradle" version should be the version set in flutter templates or newer.
- In older code any gradle version that works with the other version constraints is ok.
- In practice our customers use a large variety of gradle versions.
- If the version is intentionally different there should be a comment explaining why.
```
// OK
distributionUrl=https\://services.gradle.org/distributions/gradle-8.12.1-bin.zip
```
### kotlin
Changing kotlin versions is most likley to have an issue with another dependency and not the code under test.
- "kotlin" version should be the version set in flutter templates or newer.
- If the version is intentionally different there should be a comment explaining why.
```
// Ok
ext.kotlin_version = "1.7.10"
...
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
```