JNI編譯問題

在編譯so文件時，總會出現各類錯誤，上訴問題能夠經過下面方法解決：

The fastest way to get building is this:

(1) Locate the Android.mk file that was used to build your native code before. This is usually somewhere under the project root. Make note of the path, you'll need it in a minute. Let's call it ~/projects/myproject/myapp/src/main/jni/Android.mk.

(2) Find the build.gradle for that application. It should be in an ancestor folder of Android.mk. In our example, it would be located at ~/projects/myproject/myapp/build.gradle. If that file doesn't have "apply plugin: 'com.android.application'" near the top then it is probably the wrong one.

(3) Edit that build.gradle to point to the Android.mk file. So, add a section like this:

android {
    externalNativeBuild {
        ndkBuild {
            path "src/main/jni/Android.mk"
        }
    }
}
(4) Click "Sync Now" in Android Studio (or Build/Refresh Linked C++ Projects)

At this point, there's a good chance the build will just work. If not, we have a new issue to deal with.

FWIW, you can automate step 3 by following the steps here: https://developer.android.com/studio/projects/add-native-code.html#link-gradle