windos closes when tying to return c++

[badboy1245]

i'm trying to send a line of text from java to c and then have it send back to c to be displayed in a textview.


Why does my windows keep closing when i run this code?

c++ code


extern "C"
JNIEXPORT jstring JNICALL
Java_com_example_tony_c_MainActivity_getStrLen(JNIEnv *env, jobject instance, jstring filename) {

const char *javastring = env->GetStringUTFChars(filename , NULL ) ;

env->ReleaseStringUTFChars(filename, javastring);



return env->NewStringUTF(javastring);


}

java code

public class MainActivity extends AppCompatActivity {

// Used to load the 'native-lib' library on application startup.
static {
System.loadLibrary("native-lib");

}



// private int getStrLen;
// private Object s;


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

// Example of a call to a native method
TextView tv = findViewById(R.id.sample_text);
tStrLen());

getStrLen("hello shit this works");

}

public native int getStrLen(String javastring);

public native String getStrLen();

}

[pointerboy]

Maybe it requires some sort of "pause" function? It's a common thing especially when you're using Visual Studio with the debugging on.

[badboy1245]

how do i pause it, im using android studio.

[badboy1245]

its not the pause as soon as it hits this line " this.getStrLen() " in the textview it shutdown.