dlopen failed: library "libbinder.so" not found

[Pillar1989]

We use native-libandroidthings in our project. but it print error "dlopen failed: library "libbinder.so" not found"

apply plugin: 'com.android.application'

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.seeed.baozhu.mraa_demo"
        minSdkVersion 19
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        externalNativeBuild {
            cmake {
                cppFlags "-std=c++11 -frtti -fexceptions"
            }
        }
        ndk {
            // Specifies the ABI configurations of your native
            // libraries Gradle should build and package with your APK.
            abiFilters 'armeabi-v7a'
        }

    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    externalNativeBuild {
        cmake {
            path "CMakeLists.txt"
        }
    }
    sourceSets {
        main {
            jniLibs.srcDirs 'libs/mraa-1.8.0/jni'
        }
    }
}

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support.constraint:constraint-layout:1.1.2'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation files('libs/mraa-1.8.0/classes.jar')
}

06-20 01:35:45.560 29084-29084/com.seeed.baozhu.mraa D/AndroidRuntime: Shutting down VM
06-20 01:35:45.567 29084-29084/com.seeed.baozhu.mraa E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.seeed.baozhu.mraa, PID: 29084
java.lang.UnsatisfiedLinkError: dlopen failed: library "libbinder.so" not found
at java.lang.Runtime.loadLibrary0(Runtime.java:1016)
at java.lang.System.loadLibrary(System.java:1657)
at com.seeed.baozhu.mraa.MainActivity.(MainActivity.java:18)
at java.lang.Class.newInstance(Native Method)
at android.app.Instrumentation.newActivity(Instrumentation.java:1174)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2669)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

[proppy]

Can you confirm that the same issue happen with the official sample: https://github.com/androidthings/sample-nativepio ?

[Pillar1989]

@proppy Refer to googlearchive/tango-examples-c#117

libandroidthings link libbinder , but libbinder is non-NDK platform libraries.

https://github.com/aosp-mirror/platform_bionic/blob/master/android-changes-for-ndk-developers.md#private-api-enforced-for-api-level--24

I don't know if you've thought about it

[proppy]

@Pillar1989 are you trying to statically link libandroidthings?

It should be linked dynamically https://github.com/androidthings/sample-nativepio/blob/master/blink/src/main/cpp/CMakeLists.txt#L41, as when deployed your APK will use the one coming from the system image.

[Pillar1989]

Yes,I copied this CMakeList.txt. I still wonder how native libandroidthings get around the non-ndk rule.