Android studio C++ ndk camera

Question

I created C/C++ project in android studio and I want to use NDK camera. I wrote in my cpp file

#include <camera/NdkCameraMetadata.h>
#include <camera/NdkCameraManager.h>
#include <camera/NdkCameraDevice.h>
#include <jni.h>
#include <string>


extern "C" JNIEXPORT jstring JNICALL
Java_com_example_test_MainActivity_listDevices(JNIEnv* env, jobject)
{
   std::string text;

   ACameraIdList *camList;
   ACameraManager *camManager;

   camManager = ACameraManager_create();

   camera_status_t result = ACameraManager_getCameraIdList(camManager, &camList);

   if (result == ACAMERA_OK)
   {
       text = "Error List devices";
   }
   else
   {
       text = "Device listed";
   }

   return env->NewStringUTF(text.c_str());;
}

but Android studio is writing

"Can't resolve type ACameraIdList"

What I'm doing wrong? I just added this code into .cpp file, nothing else. Idid not changed any other files.

Answer 1

As mentioned in the comments, you need to set the minSDK to 24 or higher.

The NdkCameraDevice.h header files detects the minSDK using the __ANDROID_API__ identifier:

#if __ANDROID_API__ >= 24
      ...
typedef struct ACameraIdList {
    int numCameras;          ///< Number of camera device Ids
    const char** cameraIds;  ///< list of camera device Ids
} ACameraIdList;
      ...
#endif

This means that if the minSDK is below 24 the C preprocessor will omit the declaration of ACameraIdList and other related structures and functions. This leads to the "Can't resolve type ACameraIdList" error.