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Error in MainAcitivity.java file & no style are loading

I am new to android. I am creating an android application, but there are many errors showing in MainActivity.java. Here is a screenshot
Another problem is that no style in showing in activity_main.xml. Here is the screenshot
Although I have added appcompact_v7 jar file like this
But it's not recognizing it in android option of project propertise
I have installed Support library in SDK manager. Please tell me how to solve this problem?

It is really hard to say what is wrong there. here are some things that you should try:
first of all, there are errors in your xml file (activity_xml). Please check if xml is properly formatted and you are using right tags. For debugging purpose, please make your acitivity_xml an empty FrameLayout and see if it works.
Include android 6.0 into your build path. Clean the project and try building again. Make sure your layouts are error free before doing that.
Your eclipse is unable to detect referenced library at given location. Please make sure referenced library is at same place and ERROR-FREE. If library has error, your project won't include it.
Please solve all problems one by one. First make an error free xml, then a Hello world Activity. Run it on device or emulator. Once done, try to solve library and import problem now.
Best Suggestion: Please migrate to Android Studio and gradle for better support and learning.

UnsatisfiedLinkError for libopencv_core.so while .apk holds this library

I want to use JavaCv with my App on Android.
Therefore I followed the advice here: https://github.com/bytedeco/javacv on how to install Android 2.2 or newer. As a result the following libraries can be found under \libs\armeabi:
libjniopencv_core.so
libopencv_core.so
All classes of both libraries are also present in the classes.dex file of my .apk.
And still i get the following exception:
java.lang.UnsatisfiedLinkError: Cannot load library: soinfo_link_image(linker.cpp:1635): could not load library "libopencv_core.so" needed by "libjniopencv_core.so"; caused by load_library(linker.cpp:745): library "libopencv_core.so" not found
I tried loading libopencv_core.so via
System.loadLibrary("libopencv_core")
and
System.loadLibrary("opencv_core")
with the same outcome..
Any hint on how to solve this issue would be appreciated.
Edit1:
I had a look to see which .so files could actually be found under /data/app-lib/ccc.android.myappname...
Despite libopencv_core.so and other files can be found under lib/armeabi/ in my .apk only some of them are available for my activity under /data/app-lib/ccc.android.myappname. The others are just ignored for some unknown reason.
Can somebody help, i have no idea what is going on.
Thank you.

Here the solution i found:
I discussed this matter on the JavaCv board on Github:
https://github.com/bytedeco/javacv/issues/28
The Issue might be history with the next release, but for the meantime do as follows:
Before using JavaCv for the first time run:
static {
System.loadLibrary("tbb");
System.loadLibrary("opencv_core");
System.loadLibrary("jniopencv_core");
}
On some devices (or occasion) the intended load order get mixed up...

Importing and using a library in android studio

I am using android studio to import this project called https://github.com/Pixate/pixate-freestyle-android. However when I import it into android studio the folder under samples, freestyleshowcase doesnt seem to build. The other 2 samples buld correctly. There is a red circle around the java file with a J (error) but there is no error in the file itself. COuld someone please help me out?

You are obviously missing some libraries but it is going to be hard for anyone to tell you which since we do not know the libraries the project needs.You can try Build-->Rebuild Project or Build-->Clean Peoject if it still doesn't work, close and open Android Studio.
If that doesn't work also then you have to go the hard way of identifying the libraries need by the project samples you imported and see if you have them.

When in doubt, you can try the Library Dependency option (using Maven) as demonstrated here:
https://www.youtube.com/watch?v=6BUcx9gGQ3o
That way, you won't have to manually edit the build.gradle file.

OCR Simple example android using tesseract compilation error

I am making a library called tesstwo, and it works, but there's one problem when I'm trying to compile for Simple Android OCR. It says:
import com.googlecode.tesseract.android.TessBaseAPI;
cannot resolve library
Does anyone know what the problem and how to solve it?

Hey i found the solution for it
all u need is to build ur Ndk and How to do that?
Its simple
just take the path where to have saved the tess-two folder in the terminal(ubuntu)
for
Ubuntu:cd /home/workspace/tess-two-master/tess-two //This is my path u will have different
tess-two$: /(path where u have installed ur ndk)/ndk-build
Windows:cd /cygdrive/e/terril/workspace/tess-two-master/tess-two ; /cygdrive/e/terril/Libraries/android-ndk-r8b-windows/android-ndk-r8b/ndk-build
It will work

where is link.h in the Android NDK?

I am trying to compile a simple program using arm-linux-androideabi-g++. I am including this line im my program:
#include"link.h"
It gives error by saying no such file or directory. When i tried searching for the file I could not find it. I have searched the whole android-ndk directory and still could not find it. Can any one please help me find the file if there is any of its kind in the android ndk?
Or can i just use the link.h of /usr/include/link.h and modify it for Android somehow?

If you are talking about Bohem GC, then you can use this link.h file, it works fine with Android: http://code.google.com/p/androidmono/source/browse/trunk/PlatformPatches/link.h

You have to write a .mk file and set the path to the headers that you are using.
read this for reference:
https://groups.google.com/forum/?fromgroups#!topic/android-ndk/-_scQd5leqo