Android:FileObserver仅监控顶级目录

Question

根据文件,

"Each FileObserver instance monitors a single file or directory. If a directory is monitored, 
events will be triggered for all files and subdirectories inside the monitored directory."

我的代码就像,

    FileObserver fobsv = new FileObserver("/mnt/sdcard/") {

    @Override
    public void onEvent(int event, String path) {
        System.out.println(event+"    "+path);
    }
    };
    fobsv.startWatching();

但是,onEvent()只有在/ mnt/sdcard /中更改文件时才会触发.如果我在/ mnt/sdcard/downloads /中创建一个文件,则该方法不会被触发.

代码有问题吗？

Answer 1

有一个开源RecursiveFileObserver工作正常FileObserver应该...我正在使用它当前它是它的名称,它充当FileObserver,递归所选目录下的所有目录...

就这个 :

public class RecursiveFileObserver extends FileObserver {

public static int CHANGES_ONLY = CLOSE_WRITE | MOVE_SELF | MOVED_FROM;

List<SingleFileObserver> mObservers;
String mPath;
int mMask;

public RecursiveFileObserver(String path) {
    this(path, ALL_EVENTS);
}

public RecursiveFileObserver(String path, int mask) {
    super(path, mask);
    mPath = path;
    mMask = mask;
}

@Override
public void startWatching() {
    if (mObservers != null) return;
    mObservers = new ArrayList<SingleFileObserver>();
    Stack<String> stack = new Stack<String>();
    stack.push(mPath);

    while (!stack.empty()) {
        String parent = stack.pop();
        mObservers.add(new SingleFileObserver(parent, mMask));
        File path = new File(parent);
        File[] files = path.listFiles();
        if (files == null) continue;
        for (int i = 0; i < files.length; ++i) {
            if (files[i].isDirectory() && !files[i].getName().equals(".")
                && !files[i].getName().equals("..")) {
                stack.push(files[i].getPath());
            }
        }
    }
    for (int i = 0; i < mObservers.size(); i++)
        mObservers.get(i).startWatching();
}

@Override
public void stopWatching() {
    if (mObservers == null) return;

    for (int i = 0; i < mObservers.size(); ++i)
        mObservers.get(i).stopWatching();

    mObservers.clear();
    mObservers = null;
}

@Override
public void onEvent(int event, String path) {

}

private class SingleFileObserver extends FileObserver {
    private String mPath;

    public SingleFileObserver(String path, int mask) {
        super(path, mask);
        mPath = path;
    }

    @Override
    public void onEvent(int event, String path) {
        String newPath = mPath + "/" + path;
        RecursiveFileObserver.this.onEvent(event, newPath);
    } 

}
}

在您的应用程序中创建一个新类并将此代码复制到它,并根据您的喜好使用它!如果您觉得有用,请投票!

Answer 2

根据文件

如本期中所述,文档不正确.

代码有问题吗？

不,但FileObserver不是递归的,尽管有相反的文件.