help for java context

[chuang di]

I wrote an Xposed applet, but I can't use the system.loadlibray method due to version issues. I happened to see on the Internet that ReLinker can loadlibray. I have completed the interface display and can use it normally, but XPosed only has ordinary Class. The original system method is system.loadlibray(string), but Relinker uses Relinker.loadlibray(context, string). I have tried many methods but cannot get the Context of MainActivity. Can anyone tell me what method I can use?

[chuang di]

code:

MainActivity
import android.app.Activity;
import android.content.Context;
import java.lang.reflect.Method;
import android.content.Intent;
import android.os.Bundle;
public class MainActivity extends Activity {
    private File mLibDir;
    private File mWorkaroundDir;
    private EditText version;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    protected void onResume() {
        super.onResume();
        mLibDir = new File(getApplicationInfo().nativeLibraryDir);
        mWorkaroundDir = getDir("lib", Context.MODE_PRIVATE);
        updateTree();
        findViewById(R.id.call).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String number = "**"
                call(number);
            }
        });
    private void call(String num) {
            ReLinker.loadLibrary(MainActivity.this, "phoneloc-jni");  
            ((TextView) findViewById(R.id.tree)).setText(builder.toString());
    }
  }



other class
public class SmartDialXposed implements IXposedHookLoadPackage {
    String result =  "";
    String location = "";
    String wife = "761";
    String number = "";
    public String compare(String num) {
           ReLinker.loader(context, "phoneloc-jni");
//        i want loadlibrary in here, need context, how to write code?  
}
}

[Tim Moores]

I'm not familiar with the libraries you mention, but an Activity is a Context. How is the SmartDialXposed object created? Can you pass a reference to the Activity as a parameter?

[chuang di]

i try
public class MContext {
   private Map<String, Object> contextMap = new HashMap<>();

   public void set(String key, Object value) {
       contextMap.put(key, value);
   }

   public Object get(String key) {
       return contextMap.get(key);
   }
}
but pass context for null object

[Tim Holloway]

I added Code Tags to make the first example more readable. I recommend that you put them in yourself when posting structured text (code, XML, SQL, fixed text and so forth).

Your second example does not extend any sort of class that would have a Context. It's basically just a dictionary.

Finally, I don't like the "-jni" on that library name.  That smells like Java Native Interface and I've never heard of anyone doing JNI on Android, and I'm doubtful it would work, since I'm fairly sure that a wide variety of different processors use Android and JNI very definitely breaks the "write-once/run-anywhere" concept of Java. Is there a possibility that you can do what you need with something more off-the-shelf? Especially since if it's old code, there are likely improvements available.

[Norm Radder]

An interesting article about Xposed:  https://www.appdome.com/how-to/mobile-app-security/jailbreak-root-detection/detect-xposed-framework-protect-android-apps/#:~:text=apk%20files%20that%20can%20be,pretty%20heavily%20by%20hackers%20today.

[chuang di]

Tim Holloway wrote:Your second example does not extend any sort of class that would have a Context. It's basically just a dictionary.

I know the second example is just a dictionary, but I don't know how to write it to get the Context of MainActivity. I use hashmap to save the Context of MainActivity, but I can't get it. I don't need an interface. I just need to get the context and execute the loadlibray command. Please tell me how to write or how to expand the second example to receive the Context, thank you!

[Norm Radder]

Where is the connection between the MainActivity class and the SmartDialXposed class?
The MainActivity has a reference to the Context.  It could be passed to the SmartDialXposed class via its constructor.
For example: code this in MainActivity:  new SmartDialXposed(this) to pass a reference to the Context.

[Tim Moores]

Tim Holloway wrote:Finally, I don't like the "-jni" on that library name.  That smells like Java Native Interface and I've never heard of anyone doing JNI on Android, and I'm doubtful it would work, since I'm fairly sure that a wide variety of different processors use Android and JNI very definitely breaks the "write-once/run-anywhere" concept of Java.

There's no problem using JNI on Android. Gradle can create native code for all of ARM, ARM-64, X86 and x86-64, and ship that all in the same Android app.