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Guide To Compile jni

code in Android Studio01 JUNE 2016/ 4:00 PM / Videocon R&D

Create Android Project Open Android Studio. Select Start new Android Studio Project. Set Application name. In this guide I will usejniCompile. Set Company name. In this guide I will use ord.d2h.ideocon . hit Ne!t

In the Select the "orm "actor# your app will run onI used Phone and $a%letandselected AP& '( Android 2.) *+in,er%read-but ou can t! othe! setups.

hit Ne!t. Select Empty Actiityand hit Ne!t. "ea#e Actiity Nameand all the othe! $elds as is and hit Ne!t.

Jni Folder1. In the Projectfile viewer find pathjniCompile / app / src2. On srcfolder do Right Click -> New -> DirectoryName itjniand hit OK.

3. Ifjnifolder already available put it under src.

C Library File

All the c files should be placed under jni folder.

Example of how to define methods in c

The function name Java_eu_ratikal_helloc_ainActivit!_"et#trin"is based

on this patternJava___.

* can be found in the fist line of projects ainActivit!.javafile.

* can also be found in ainActivit!.javafile and is the class

name! in this case MainActivity.

* you decide it" In this e#ample id getString.

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Android.mk%.

. Insidejnifolder create a file named Android.mk$same procedure with %ello&.c'.'. (ndroid.m) is a the file that instructs nd)build how to compile and create the library

for java to call the &.

4. (dd the followin+ code in Android.mk

(. "#C$"_%$&' () *+call my-,ir

incl!,e *+C".$R_$R0

"#C$"_1#D2". () helloc

"#C$"_0RC_34".0 () 'elloC5c

incl!,e *+624"D_0'$R.D_"46R$R7

S)ip i* $le al!ead a#ailable

Application.mk

Insidejnifolder create a file named Application.mk$same procedure with %ello&.c and

(ndroid.m)'.

(pplication.m) is a the file that instructs nd)build how to compile and create the library for java to

call the &.

(dd the followin+ code in Application.mk

$%%_$64 () armea8i armea8i-v9a mips :;

$%%_%"$&3#R1 () an,roi,-=

,ou can s)ip creatin+ (pplication.m) if you now that armeabi is fine for your testdevice. If you dont understand this! create the file and probably you are +oin+ tobe o)"

Build the library

Now build the library"

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)

In the terminal of (ndroid studio +ive the below command to +enerate the .so files

* c, app/src/jni

app/src/jni * path-to-n,k-,irectory/n,k-8!il,

Moe !le" to jniLib" #older

jni$ibsis the folder where function 0ystem5loa,"i8rary+55 searches for nativelibraries.

n,k-8!il,created folderjniCompile/app/src/li8s. -ename and move this folder tojniCompile/app/src/main/jni"i8s.

Load and Call the natie C #unction #rom jaa

+se 0ystem5loa,"i8rary+?name o 5so @le witho!t e:tensionA in a static bloc) to

i,po!t in a sepa!ate utilit class . -his class should decla!e the ,ethods o* lib with natieeyword

$hi# can %e done within actiity or any cla## %ut recommended to create a #eparate utility cla##

"or code cleanline##