Question

我有一个获取tcp连接列表的类，我得到这个列表并在ListView中显示它。我想刷新这个ListView并每2-3秒显示一次新的连接（连接监控）。

        //GetTcpConnections.java

        package Core;

        import android.content.Context;
        import android.os.AsyncTask;
        import android.os.CountDownTimer;
        import android.os.Handler;
        import android.util.Log;

        import java.io.BufferedReader;
        import java.io.File;
        import java.io.FileReader;
        import java.util.ArrayList;
        import java.util.Timer;
        import java.util.TimerTask;

        import Adapters.ConnectionsAdapter;
        import Structs.TcpConnectionData;
        import Utils.TcpUtils;



        public class GetTcpConnection {

           Context context;

            private int interval = 2;

            private TcpConnectionLitener litener = null;

            public GetTcpConnection(Context ctx,TcpConnectionLitener lst){
                context = ctx;
                litener = lst;
            }




            public interface TcpConnectionLitener{
                public void onRecvData(ArrayList<TcpConnectionData> result);
            }


            private void waitTime(int sec) {
                try {
                    // sleep
                    Thread.sleep(1000*sec);
                } catch (InterruptedException e) { }
            }

            class task extends AsyncTask <GetTcpConnection,Void,ArrayList<TcpConnectionData>>{





                @Override
                protected ArrayList<TcpConnectionData> doInBackground(GetTcpConnection... data) {



                    waitTime(2);



                    return getConnections();


                }

                @Override
                protected void onPostExecute(ArrayList<TcpConnectionData> tcpConnectionDatas) {
                    super.onPostExecute(tcpConnectionDatas);


                    litener.onRecvData(tcpConnectionDatas);



                }
            }


            public void startQue() {


        /*  TimerTask  have error

                 TimerTask timerTask = new TimerTask() {

                    @Override
                    public void run() {

                        new task().execute();
                    }
                };

                Timer timer = new Timer();
                timer.scheduleAtFixedRate(timerTask, 0, interval);
        */


                while(true){
                    waitTime(interval);
                    new task().execute();

                }

                }


            }


        // Get tcp connection list

            public ArrayList<TcpConnectionData> getConnections(){
               ............
               ............

                return  output;

            }
        }

这是包含ui（listview）的活动

        /// TcpConnectionsActivity.java
        package ir.nancy.parentalcontroller;

        import android.support.v7.app.ActionBarActivity;
        import android.os.Bundle;
        import android.view.Menu;
        import android.view.MenuItem;
        import android.widget.ListView;

        import java.util.ArrayList;

        import Adapters.ConnectionsAdapter;
        import Core.GetTcpConnection;
        import Structs.TcpConnectionData;

        import Core.GetTcpConnection.TcpConnectionLitener;

        public class TcpConnectionActivity extends ActionBarActivity implements TcpConnectionLitener {

            private GetTcpConnection tcpConnection;
            private ListView listView;

            private ArrayList<TcpConnectionData> datas;



            private ConnectionsAdapter adapter;

            private Integer[] items;


            @Override
            public void onRecvData(ArrayList<TcpConnectionData> result) {
                if (result == null){
                    return;
                }

                if (datas != null){
                    if (datas.equals(result)){
                        return;
                    }
                }

                datas = result;
                if (datas.size() > 0) {
                    items = new Integer[datas.size()];

                    int i = 0;

                    for (TcpConnectionData _i : datas) {
                        items[i] = _i.uid;
                    }

                    adapter = new ConnectionsAdapter(this, items, datas);

                    listView.setAdapter(adapter);

                }
            }

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

                tcpConnection = new GetTcpConnection(this,this);
                listView = (ListView) findViewById(R.id.listView);

                     tcpConnection.startQue();

            }


            @Override
            public boolean onCreateOptionsMenu(Menu menu) {
                // Inflate the menu; this adds items to the action bar if it is present.
                getMenuInflater().inflate(R.menu.menu_tcp_connection, menu);
                return true;
            }

            @Override
            public boolean onOptionsItemSelected(MenuItem item) {
                // Handle action bar item clicks here. The action bar will
                // automatically handle clicks on the Home/Up button, so long
                // as you specify a parent activity in AndroidManifest.xml.
                int id = item.getItemId();

                //noinspection SimplifiableIfStatement
                if (id == R.id.action_settings) {
                    return true;
                }

                return super.onOptionsItemSelected(item);
            }
        }

事实上问题是泄漏内存（android中的关闭/等待对话框）。我怎么解决它？

问题在哪里？

Answer 1

您在GetTcpConnection类中泄漏上下文（一个巨大的对象），因为您使用sleep方法阻止该线程。要以指定的时间间隔执行任务，请使用AlarmManager或ScheduledExecutorService。不要使用Thread.sleep（long）方法。永远不要将上下文传递给会比它活得更久的类（Activity，对于这个实例），或者垃圾收集器将无法释放它（this是关于android中的内存泄漏的好文章，当它们发生时如何避免它们。）

在android中每2秒获取一次tcp连接

1 个答案: