RN 0.47 seems to be working fine with gradle 4.0 and compileSdkVersion / buildToolsVersion 26

[pocesar]

The build went from 6 minutes (for a 35 file project) down to 24s, on a second wind after the gradle daemon has already started with at least 1500MB memory...

Maybe encourage new projects to use those optimized settings, since I'm also using a lot of third party android Java modules, with no incompatibilities issues.

my build.gradle looks like this:

// Top-level build file where you can add configuration options common to all sub-projects/modules.
ext {
    compileSdkVersion = 26 // Or what version you want (latest is recommended)
    buildToolsVersion = '26.0.1' // same thing
}

subprojects { subproject ->
    afterEvaluate{
        if((subproject.plugins.hasPlugin('android') || subproject.plugins.hasPlugin('android-library'))) {
            android {
                compileSdkVersion rootProject.ext.compileSdkVersion
                buildToolsVersion rootProject.ext.buildToolsVersion
            }
        }
    }
}

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.3.+'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

gradle-wrapper.properties:

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-4.0-all.zip

in build.gradle inside app folder

android {
    compileSdkVersion rootProject.ext.compileSdkVersion
    buildToolsVersion rootProject.ext.buildToolsVersion
    // ...

also, I was this settings since 0.46, and react-native-git-upgrade without any issues as well

[kelset]

Are you using these settings for an app out in production?

[pocesar]

yes, I am, and also using with code-push

[kelset]

Interesting, how long have you been using these settings? Is it performing well in Android 7?

Since I've upped to 25 (both compile and buildtools) some users have crashes I don't know how to debug (#15429) on Nougat.

And, follow-up, if you submit to the Google Play Store a build targetting 26, can you reverse to 25? 'cause I know you can't when upping from 23 to 25 it's a "no turning back" point.

[pocesar]

well, I'm not using Google Play, so I'm not sure. I'm testing on Samsung J7 with Android 6.0.1 and Android 7 as well, both seems to be working fine with a lot of intricate third party modules (like react-native-maps, react-native-camera, etc)

That error doesn't seem to be a problem with the buildTools per se, but it might be related to the SDK version, and guess it might be some bugs since it's the 'edge' of the Android SDKs (a quick googling showed that is a pretty common error on native Android using Java, even without react-native)

[iegik]

distributionUrl=https\://services.gradle.org/distributions/gradle-4.1-milestone-1-all.zip

Still have issues:
#14980

[kelset]

Ok, I've tried to update my app too to 26 settings provided above, everything seems to be running fine for now.

I think tbh this issue could be closed, anyway, because it's not really "an issue".

[iegik]

Ok. But I still cannot say that RN is stable.

http://services.gradle.org/versions/current

[agrass]

it is not recommended to use compileSdkVersion 26 on production?? What do you guys think?

[iegik]

Some braking changes not resolved in Android Oreo (7+, 8.0.0):

• Remote JS Debugging crashes app after 30 seconds #12289
• Android Oreo (8.0) Support #15601

[pocesar]

@agrass I think you mean targetSdkVersion you can set that regardless of the compileSdkVersion (usually 23)

[agrass]

@pocesar I have targetSdkVersion 22, and I changed the buildToolsVersion and compileSdkVersion from 23 to 26 in order to use a library with some dependencies. Now I'm a bit scared about this, because I'm not sure about the compatibility in some phones building RN with v26. Probably I'm going to roll back to v23

[agrass]

thanks @iegik for the references. what about v25, it is the same??

[iegik]

25 - more stable

    defaultConfig {
        applicationId "com.acme.app"
        // An integer designating the minimum API Level required for the application to run.
        // The Android system will prevent the user from installing the application if the system's API Level
        // is lower than the value specified in this attribute. You should always declare this attribute.
        minSdkVersion 16
        // This attribute informs the system that you have tested against the target version
        // and the system should not enable any compatibility behaviors to maintain your app's forward-compatibility
        // with the target version. The application is still able to run on older versions (down to minSdkVersion).
        // FIXME: Support Android Oreo (7+, 8.0.0)
        targetSdkVersion 25
        // An integer designating the maximum API Level on which the application is designed to run.
        // maxSdkVersion ??
        versionCode 1
        versionName "${packageJSON.version}"
        ndk {
            // Test all dependences on x64 devices (might not work)
            // https://github.com/facebook/react-native/issues/2814
            abiFilters 'armeabi-v7a', 'x86'
        }
        // Enabling multidex support.
        // https://stackoverflow.com/questions/41426853/java-lang-classnotfoundexception-in-dalvik-system-basedexclassloader-findclass
        multiDexEnabled true
        packagingOptions {
            exclude "lib/arm64-v8a/librealm-jni.so"
        }
    }

[agrass]

thanks, but suitable for production?? Anyone already using it?

[iegik]

I would not to promote stable release since of https://github.com/facebook/react-native/releases/tag/v0.40.0 because:

• in iOS not everywhere <React/ prefix are added and don't forget that importing with prefix and without cause Duplicate declaration error in outdated dependent components
• Android builds are crashes with ProGuard enabled [0.48.1] [Android] Bug: no "Lcom/facebook/jni/HybridData;" field "mHybridData" in class #15621

[kelset]

thanks, but suitable for production?? Anyone already using it?

I've been using 25 in prod and it's mostly stable, aside from an Android 7 issue.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Maybe the issue has been fixed in a recent release, or perhaps it is not affecting a lot of people. If you think this issue should definitely remain open, please let us know why. Thank you for your contributions.

[pocesar]

not many tests were done in recente android sdk versions. Google itself ask to always use the latest SDK versions, and RN is still stuck in 23 by default. Maybe create a matrix testing for the CI?

[kelset]

I think this should remain open, currently I'm trying to use version 26 on our prod app and I'm facing some weird issues only when I test the app on Android 8.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Maybe the issue has been fixed in a recent release, or perhaps it is not affecting a lot of people. If you think this issue should definitely remain open, please let us know why. Thank you for your contributions.

[pocesar]

#17287 shows urgency on the issue

[nerdmed]

Any news on this? Updating Gradle makes our Android builds 50x faster. That is really significant and would benefit the developer experience!

[slorber]

Hey, just wanted to point out that when ejecting from Expo, you already use SDK26. Many of us have SDK26 Expo ejected apps in production (I have one, Expo SDK22, Android SDK26), so I guess it should be safe to target SDK26. I've been fine with Gradle 4.1.

[dulmandakh]

Closing this issue, because RN 0.57 will have SDK 27, Support library 27.x, gradle 4.x and android gradle plugin 3.x