Issue while building

[jharitesh1]

Pls help me to fix below issue.

/Official/workspace/DermAsist/opencv_sample/app/src/main/jni/DetectionBasedTracker.cpp
Error:(4, 33) opencv2/objdetect.hpp: No such file or directory
compilation terminated.
/Official/workspace/DermAsist/opencv_sample/app/src/main/jni/Tutorial2.cpp: In function 'void Java_com_jnardari_opencv_1androidsamples_activities_Tutorial2Activity_FindFeatures(JNIEnv_, jobject, jlong, jlong)':
/Official/workspace/DermAsist/opencv_sample/app/src/main/jni/Tutorial2.cpp
Error:(19, 67) error: invalid user-defined conversion from 'int' to 'const string& {aka const std::basic_string&}' [-fpermissive]
Ptr detector = FastFeatureDetector::create(50);
^
/Users/apple/Library/Android/sdk/ndk-bundle/sources/cxx-stl/gnu-libstdc++/4.9/include/string
Information:(52) (Unknown) In file included
/Users/apple/Library/Android/sdk/ndk-bundle/sources/cxx-stl/gnu-libstdc++/4.9/include/bits/basic_string.h
Information:(495, 7) candidate is: std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const CharT, const _Alloc&) [with _CharT = char; Traits = std::char_traits; Alloc = std::allocator]
Information:(495, 7) no known conversion for argument 1 from 'int' to 'const char'
/Official/workspace/DermAsist/opencv_sample/app/src/main/jni/Tutorial2.cpp:19:67: error: invalid conversion from 'int' to 'const char' [-fpermissive]
Information:(495, 7) initializing argument 1 of 'std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, const _Alloc&) [with _CharT = char; _Traits = std::char_traits; _Alloc = std::allocator]'
Error:Execution failed for task ':app:compileArmeabiDebugArmNdklibrarysampleSharedLibraryNdklibrarysampleMainCpp'.

Multiple build operations failed.
C++ compiler failed while compiling DetectionBasedTracker.cpp.
C++ compiler failed while compiling Tutorial2.cpp.
See the complete log at: file:///Official/workspace/DermAsist/opencv_sample/app/build/tmp/compileArmeabiDebugArmNdklibrarysampleSharedLibraryNdklibrarysampleMainCpp/output.txt
Information:BUILD FAILED
Information:Total time: 1.936 secs
Information:3 errors

[iRazvan]

I have the same issue, core.hpp not found. Did you fix it?