Android ndk compiling error: unknown type name 'JNIEnv'
<p>I am coding in Android studio, would make a .so file . But I cannot resolve this problem . Though I have included  who can help me?</p>

<p><strong>My jni folder and error info img</strong> :</p>

<p><a href="https://i.stack.imgur.com/Ankmm.png" rel="nofollow noreferrer">http://i.stack.imgur.com/Ankmm.png</a></p>

<p><strong>My Android.mk file:</strong></p>

<hr>

<pre><code>include $(CLEAR_VARS) 
LOCAL_MODULE := swresample-prebuilt 
LOCAL_SRC_FILES := $(LOCAL_PATH)/../../libs/libswresample-2.so 
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/libswresample include 
$(PREBUILT_SHARED_LIBRARY)

include $(CLEAR_VARS)
LOCAL_MODULE := ffmpegplay
LOCAL_SRC_FILES := NativeUtil.c FFmpegCodec.c
LOCAL_LDLIBS :=-llog
LOCAL_SHARED_LIBRARIES := avcodec-prebuilt avformat-prebuilt swscale-prebuilt avutil-prebuilt  swresample-prebuilt
LOCAL_CFLAGS := -D__STDC_CONSTANT_MACROS
include $(BUILD_SHARED_LIBRARY)
</code></pre>