Question

您好我正在使用android.I我希望从服务数据更新ui。因此，我通过广播接收器成功获得服务数据，并在价值变化时更新了listview。我的问题是在活动运行期间，如果我最小化活动然后最大化，另一个接收器将被注册，并将重复我的列表视图数据。如何在最大化后设置一个接收器？这是我的代码

public class MainActivity extends Activity {

        ListView l1;
       ArrayList<String> t1=new ArrayList<String>();
       ArrayList<String> d1=new ArrayList<String>();
       ArrayList<Integer> i1=new ArrayList<Integer>();


    MyReceiver myReceiver;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        l1=(ListView)findViewById(R.id.listView1);
        //l1.setAdapter(new dataListAdapter(t1,d1,i1));


    }
    @Override
    protected void onStart() {
     // TODO Auto-generated method stub

          //Register BroadcastReceiver
          //to receive event from our service



          myReceiver = new MyReceiver();
          IntentFilter intentFilter = new IntentFilter();
          intentFilter.addAction(MyService.MY_ACTION);
          registerReceiver(myReceiver, intentFilter);

          //Start our own service
          Intent intent = new Intent(MainActivity.this,
                  com.example.androidservice.MyService.class);
          startService(intent);
          super.onStart();

    }

    @Override
    protected void onStop() {

     unregisterReceiver(myReceiver);
     stopService(new Intent(MainActivity.this,MyService.class));
     super.onStop();
    }

    @Override
    protected void onPause() {

     //unregisterReceiver(myReceiver);
     stopService(new Intent(MainActivity.this,MyService.class));
     super.onPause();
    }

    private class MyReceiver extends BroadcastReceiver{

     @Override
     public void onReceive(Context arg0, Intent arg1) {

      String datapassed1 = arg1.getStringExtra("DATAPASSED1");
      String datapassed2 = arg1.getStringExtra("DATAPASSED2");

      Toast.makeText(MainActivity.this,
        "Triggered by Service!\n"
        + "Data passed: " + String.valueOf(datapassed1),
        Toast.LENGTH_SHORT).show();


      t1.add(datapassed1);
      d1.add(datapassed2);

      for(int i=0;i<t1.size();i++)
      {

          i1.add(R.drawable.ic_launcher);

      }





      l1.setAdapter(new dataListAdapter(t1,d1,i1));

     }

    }

    class dataListAdapter extends BaseAdapter {
       ArrayList<String> Title, Detail;
        ArrayList<Integer> imge;

        dataListAdapter() {
            Title = null;
            Detail = null;
            imge=null;
        }

        public dataListAdapter(ArrayList text, ArrayList text1,ArrayList text3) {


            notifyDataSetChanged();

            Title = text;
            Detail = text1;
            imge = text3;

        }

        public int getCount() {
            // TODO Auto-generated method stub
            return Title.size();
        }

        public Object getItem(int arg0) {
            // TODO Auto-generated method stub
            return null;
        }

        public long getItemId(int position) {
            // TODO Auto-generated method stub
            return position;
        }

        public View getView(int position, View convertView, ViewGroup parent) {

            LayoutInflater inflater = getLayoutInflater();
            View row;
            row = inflater.inflate(R.layout.custom, parent, false);
            TextView title, detail;
            ImageView i1;
            title = (TextView) row.findViewById(R.id.title);
            detail = (TextView) row.findViewById(R.id.detail);
            i1=(ImageView)row.findViewById(R.id.img);
            title.setText(Title.get(position));
            detail.setText(Detail.get(position));
            i1.setImageResource(imge.get(position));

            return (row);
        }
    }


    }

Answer 1

注册广播接收器并在onCreate（）中启动服务 un注册接收器并在onDestroy（）中停止服务。

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    l1=(ListView)findViewById(R.id.listView1);
    //l1.setAdapter(new dataListAdapter(t1,d1,i1));
    //Register BroadcastReceiver
      //to receive event from our service
      myReceiver = new MyReceiver();
      IntentFilter intentFilter = new IntentFilter();
      intentFilter.addAction(MyService.MY_ACTION);
      registerReceiver(myReceiver, intentFilter);

      //Start our own service
      Intent intent = new Intent(MainActivity.this,
              com.example.androidservice.MyService.class);
      startService(intent);


}

@Override
protected void onDestroy() {

 unregisterReceiver(myReceiver);
 stopService(new Intent(MainActivity.this,MyService.class));
 super.onDestroy();
}

Answer 2

您应该在BroadcastReceiver中注册onResume并在onPause中取消注册。之后，您不需要在任何其他活动的生命周期方法中注册/取消注册。

@Override
protected void onResume() {
  super.onResume();
  registerReceiver(myReceiver, new IntentFilter(MyService.MY_ACTION));
}

@Override
protected void onPause() {
  super.onPause();
  unregisterReceiver(myReceiver);
}

我希望这会有所帮助。

Answer 3

这里应该有一些东西（也许是你的清单）。对我来说，如何处理你的接收器似乎是正确的（你不必使用onPause-onResume来注册/取消注册）。

请确保您也不要在清单文件中注册接收器。

当活动最小化和最大化时，Android广播接收器会多次注册

3 个答案: