opencv4android：构建路径不完整

Question

I am trying to compile opencv4android library 2.4.10 on my mac using eclipse, to get to run samples. after going through a lot of trouble, I have been successful with compiling native code. But after that I get this error:

The project was not built since its build path is incomplete. Cannot find the class file for java.lang.Object. Fix the build path then try building this project OpenCV Library - 2.4.10 Unknown Java Problem.

I have tried to manually add JRE by going to "project properties -> java build path -> libraries" and edit the problematic library(unable to get system library for the project). But each time I try to edit that the only option I have is opencv library 2.4.10 - the same as project itself and I can't replace that with proper JRE.

Any idea how can I fix this?

Answer 1

I think you have not installed the appropriate Android SDK platforms: 9 and 11 are referenced in the error message. This documentation describes how to set Android SDK properly with downloading more components.

However it is not necessary to download all the missing SDKs. You can modify the required target to your already installed one (at least target 8) in project.properties file of eg 15-puzzle's directory.

Answer 2

It seems that the problem was originating from my lack of experience in using native code in an application. what happened was, when importing and setting up the library project, eclipse automatically changed to C/C++ perspective. in which it wouldn't compile the application. as soon as I found out and change the perspective everything worked properly. as simple as that!