NDK開發常見錯誤

1. 在jni目錄下沒有發現Android.mk文件

   Android NDK: Your APP_BUILD_SCRIPT points to an unknown file: ./jni/Android.mk
   

2. c文件中沒有導入jni.h的頭文件.

   jni/CommonError.c:4:1: error: unknown type name 'JNIEXPORT'
   jni/CommonError.c:4:19: error: expected '=', ',', ';', 'asm' or '__attribute__'
   before 'JNICALL'
   jni/CommonError.c:4:19: error: unknown type name 'JNICALL'
   

3. c代碼實現的方法沒有寫形參的名字.

   jni/CommonError.c: In function 'Java_com_ycy_commonerrordemo_MainActivity_
   sayHelloInC':
   jni/CommonError.c:6:3: error: parameter name omitted
   jni/CommonError.c:6:3: error: parameter name omitted
   jni/CommonError.c:8:13: error: 'env' undeclared (first use in this function)
   jni/CommonError.c:8:13: note: each undeclared identifier is reported only once f
   or each function it appears in
   

4. 調用native方法, 沒有加載.so文件.

   No implementation found for native Lcom/ycy/commonerrordemo/MainActivity;.sayHelloInC ()Ljava/lang/String;
   

5. 加載.so文件時, 名字寫錯.

   java.lang.UnsatisfiedLinkError: Couldn't load libcommonerror.so: findLibrary returned null
   

6. 當前生成的arm平臺下的.so文件, 運行在了x86的平臺模擬器下.

   java.lang.UnsatisfiedLinkError: Couldn't load libcommonerror.so: findLibrary returned null
   

   • 解決方案: 在jni的目錄下, 創建一個Application.mk, 內容如下:

     # 生成所有的機器碼.
     APP_ABI := all
     
     # 生成單個平臺的機器碼
     APP_ABI := x86 armeabi