I am trying to monitor all files operations(create, read, write, modify, delete) in ‘/sdcard’ directory. It seems the class FileObserver could do the job from the documentation”https://developer.android.com/reference/android/os/FileObserver.html”. Iimplement onEvent method like this,
@Override
public void onEvent(int event, @Nullable String path) {
Log.d("sdevent",""+event);
switch(event) {
case FileObserver.ALL_EVENTS:
Log.d("sdcardlistener", "path:"+ path);
break;
case FileObserver.CREATE:
Log.d("sdcardlistener", "path:"+ path);
break;
}
}
But when I try it on my Android studio 3.5.3 using emulator Pixel2(API 28) and my own phone which is Android Q now, I cannot get any event on path ‘/sdcard’ or its subdirectory ,‘/sdcard/DCIM’ for example. The code is like this.
SDCardListener listener1=new SDCardListener("/sdcard");
listener1.startWatching();
If I change the path to a app-specific one, like ‘/sdcard/Android/data/com.example.myfiletest(my app name)/files/apple’, it seems to work for the directory and its fist subdirectory.
SDCardListener listener2=new SDCardListener("/sdcard/Android/data/com.example.myfiletest/files/apple");
listener2.startWatching();
Since this situation doesn’t match documentation, I want to know where is the problem. And is there a way to monitor all file changes in externel storage if FileObserver not capable to do so.
