Detect File Change using FileObserver on Android

Using FileObserver

    
        FileObserver f;

        f = createWatchList("/sdcard/");
        f.startWatching();
        watchList.add(f);
        f = createWatchList("/sdcard/tmp");
        f.startWatching();
        watchList.add(f);
    }

    private FileObserver createWatchList(String path){
    	File file = new File(path);
    	if (file == null || ! file.isDirectory()){
    		Log.d(TAG, "path is not directory.");
    		return null;
    	}
    	
		return new PathFileObserver(path);
    }