Question

我正在使用此代码，但它会出错，我无法追踪。任何帮助，将不胜感激。这是代码：

package com.example.test;

import java.net.DatagramPacket;
import java.net.DatagramSocket;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.widget.TextView;


public class MainActivity extends Activity {
TextView display;

private MyDatagramReceiver myDatagramReceiver = null;
protected void onResume() {
   myDatagramReceiver = new MyDatagramReceiver();
   myDatagramReceiver.start();
}

protected void onPause() {
// myDatagramReceiver.kill();
}
@Override
protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.activity_main);
   display=(TextView) findViewById(R.id.textView1);
}

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

private class MyDatagramReceiver extends Thread {
   private boolean bKeepRunning = true;
   private String lastMessage = "";

   public void run() {
      String message;
      byte[] lmessage = new byte[100];

      try {
         DatagramSocket socket = new DatagramSocket(2690);
         Log.v("Run", "Socket Created");
         while(bKeepRunning) {
            DatagramPacket packet = new DatagramPacket(lmessage, lmessage.length);
            socket.receive(packet);
            message = new String(lmessage, 0, packet.getLength());
            lastMessage = message;
            runOnUiThread(updateTextMessage);
            Log.v("Receiving", "packet recvd");
         }
         if (socket != null) {
            socket.close();
            Log.v("SOC", "Socket closed");
         }
      } catch (Throwable e) {
         e.printStackTrace();
      }
   }
}

public void kill() { 
   bKeepRunning = false;
}

public String getLastMessage() {
   return lastMessage;
}

private Runnable updateTextMessage = new Runnable() {
   public void run() {
      if (myDatagramReceiver == null) return;
         display.setText(myDatagramReceiver.getLastMessage());
      }
   };
}
}

以下是错误：

11-14 03:04:06.240: E/AndroidRuntime(881): FATAL EXCEPTION: main
11-14 03:04:06.240: E/AndroidRuntime(881): Process: com.example.test, PID: 881
11-14 03:04:06.240: E/AndroidRuntime(881): java.lang.RuntimeException: Unable to resume activity {com.example.test/com.example.test.MainActivity}: android.util.SuperNotCalledException: Activity {com.example.test/com.example.test.MainActivity} did not call through to super.onResume()
11-14 03:04:06.240: E/AndroidRuntime(881): java.lang.RuntimeException: Unable to resume activity {com.example.test/com.example.test.MainActivity}: android.util.SuperNotCalledException: Activity {com.example.test/com.example.test.MainActivity} did not call through to super.onResume()
11-14 03:04:06.240: E/AndroidRuntime(881): Caused by: android.util.SuperNotCalledException: Activity {com.example.test/com.example.test.MainActivity} did not call through to super.onResume()

由于

Answer 1

在代码中添加缺少的超级呼叫：

protected void onResume() {
  super.onResume();
  myDatagramReceiver = new MyDatagramReceiver();
  myDatagramReceiver.start();
}

protected void onPause() {
  super.onPause();
  // myDatagramReceiver.kill();
}

Answer 2

问题不在于UDP，“以下是错误”已经说明了错误。如：

MainActivity did not call through to super.onResume()

这意味着，你必须将super.onResume（）作为覆盖方法的第一行，这就是你应该做的：

@Override
public void onResume(){
   super.onResume();
   ...
}

除了同样的观点，您可以覆盖其他活动方法。

创建UDP服务器时出现致命错误

2 个答案: