我的onEvent()部分文件观察器方法不起作用

时间:2015-10-24 11:48:43

标签: java android file events fileobserver

我已经在这里扫描了所有相关的问题和答案,但我仍然无法找到解决方案。

服务类文件:

public class otser extends Service {

private WindowManager windowManager;
private ImageView chatHead;

@Override public IBinder onBind(Intent intent) {

    return null;
}

@Override public void onCreate() {
    super.onCreate();

    windowManager = (WindowManager) getSystemService(WINDOW_SERVICE);

    chatHead = new ImageView(this);

    chatHead.setOnClickListener(new View.OnClickListener() {


        @Override
        public void onClick(View v) {

        }
    });

    FileObserver observer = new FileObserver(android.os.Environment.getExternalStorageDirectory().toString() + "/Pictures/Screenshots") {
        @Override
        public void onEvent(int event, String file) {
            event &= FileObserver.ALL_EVENTS;

            if(event == FileObserver.CREATE){
                Toast.makeText(getApplicationContext(), "screenshot taken",
                        Toast.LENGTH_LONG).show();
            }
        }
    };

    observer.startWatching(); // start the observer


    Toast.makeText(getApplicationContext(), "service: OK",
            Toast.LENGTH_SHORT).show();

}}

根据其他帖子,我仔细检查了路径,通过以编程方式创建文件,它确实存在并且正确。

活动类:

public class Home extends Activity {

Button showChatHead;
Button stopService;
@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_home);


    showChatHead = (Button) findViewById(R.id.gomb);
    stopService= (Button) findViewById(R.id.gomb2);

    showChatHead.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            Intent i = new Intent(getApplicationContext(), ChatHeadService.class);
            startService(i);
        }
    });

   stopService.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            Intent i = new Intent(getApplicationContext(), ChatHeadService.class);
            stopService(i);
        }
    });
}}

服务类链接得很好,弹出最后一个Toast消息,结论只是跳过了观察者。

有什么想法吗?

提前致谢!

较新版本:

FileObserver fileObserver = new FileObserver(android.os.Environment.getExternalStorageDirectory().toString() + "/Pictures/Screenshots") {
        @Override
        public void onEvent(int event, String path) {

            Toast.makeText(getApplicationContext(), "method entered", Toast.LENGTH_SHORT).show();

            if (event == FileObserver.CREATE) {
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        Toast.makeText(getApplicationContext(), "File created", Toast.LENGTH_SHORT).show();
                    }
                });
            }
        }
    };

    fileObserver.startWatching();

未输入onEvent方法,输入"方法"吐司没有出现。

1 个答案:

答案 0 :(得分:0)

提到了onEvent-Method文档中的

,它将在另一个线程上运行,你应该考虑这个。使用处理程序,Toa​​st消息应该出现,如下所示:

private Handler handler = new Handler();

@Override
public void onCreate() {
    fileObserver = new FileObserver("path") {
        @Override
        public void onEvent(int event, String path) {
            if (event == FileObserver.CREATE) {
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        Toast.makeText(FileWatcher.this, "File created", Toast.LENGTH_SHORT).show();
                    }
                });
            }
        }
    };
    fileObserver.startWatching();
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