我已经编写了这段代码以在按下 imageview 时通过套接字发送数据
它工作正常但是在我离开 imageview 之后它仍然发送数据
我确信问题出在 android 部分。
这段代码有什么问题？
package com.example.paradroid;
import java.io.IOException;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import android.util.Log;
public class MainActivity extends Activity {
static final String RIGHT = "2";
static final String LEFT = "4";
static final String UP = "1";
static final String DOWN = "3";
static final String STOP = "5";
InetAddress serverAddress;
Socket socket;
// ---all the Views---
static TextView txtMessagesReceived;
EditText txtMessage;
// ---thread for communicating on the socket---
CommsThread commsThread;
// ---used for updating the UI on the main activity---
static Handler UIupdater = new Handler() {
@Override
public void handleMessage(Message msg) {
int numOfBytesReceived = msg.arg1;
byte[] buffer = (byte[]) msg.obj;
// ---convert the entire byte array to string---
String strReceived = new String(buffer);
// ---extract only the actual string received---
strReceived = strReceived.substring(0, numOfBytesReceived);
// ---display the text received on the TextView---
// txtMessagesReceived.setText(txtMessagesReceived.getText()
// .toString() + strReceived);
}
};
private class CreateCommThreadTask extends
AsyncTask<String[], Integer, Void> {
@Override
protected Void doInBackground(String[]... params) {
try {
// ---create a socket---
serverAddress = InetAddress.getByName(params[0][0]);
int port = Integer.parseInt(params[0][1]);
// --remember to change the IP address above to match your own--
socket = new Socket(serverAddress, port);
commsThread = new CommsThread(socket);
commsThread.start();
} catch (UnknownHostException e) {
Log.d("Sockets", e.getLocalizedMessage());
} catch (IOException e) {
Log.d("Sockets", e.getLocalizedMessage());
}
return null;
}
}
private class WriteToServerTask extends AsyncTask<String, Void, Void> {
protected Void doInBackground(String... data) {
commsThread.write(data[0]);
return null;
}
}
private class CloseSocketTask extends AsyncTask<Void, Void, Void> {
@Override
protected Void doInBackground(Void... params) {
try {
socket.close();
} catch (IOException e) {
Log.d("Sockets", e.getLocalizedMessage());
}
return null;
}
}
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ---get the views---
final ImageView im_up = (ImageView) findViewById(R.id.imageView2);
final ImageView im_right = (ImageView) findViewById(R.id.imageView3);
final ImageView im_down = (ImageView) findViewById(R.id.imageView1);
final ImageView im_left = (ImageView) findViewById(R.id.imageView4);
im_up.setOnTouchListener(new TheOnTouchListner(1));
im_right.setOnTouchListener(new TheOnTouchListner(2));
im_down.setOnTouchListener(new TheOnTouchListner(3));
im_left.setOnTouchListener(new TheOnTouchListner(4));
}
private class TheOnTouchListner implements OnTouchListener {
private Handler mHandler;
private int tag;
public TheOnTouchListner(int t) {
this.tag = t;
}
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
if (event.getAction() == MotionEvent.ACTION_DOWN) {
if (mHandler != null)
return true;
mHandler = new Handler();
mHandler.postDelayed(mAction, 500);
} else if (event.getAction() == MotionEvent.ACTION_UP) {
if (mHandler == null)
return true;
mHandler.removeCallbacks(mAction);
mHandler = null;
return false;
}
return false;
}
Runnable mAction = new Runnable() {
@Override
public void run() {
onClickSend(tag);
mHandler.postDelayed(this, 500);
}
};
}
public void onClickSend(int tag) {
// ---send the message to the server---
if (tag == 1) {
sendToServer(UP);
} else if (tag == 2) {
sendToServer(RIGHT);
} else if (tag == 3) {
sendToServer(DOWN);
} else if (tag == 4) {
sendToServer(LEFT);
}
}
public void onClickConnect(View view) {
String[] params = new String[2];
params[0] = ((EditText) findViewById(R.id.IPText)).getText().toString();
params[1] = ((EditText) findViewById(R.id.PortText)).getText()
.toString();
new CreateCommThreadTask().execute(params);
Toast.makeText(getBaseContext(), "connected!", Toast.LENGTH_SHORT)
.show();
}
private void sendToServer(String message) {
// byte[] byteArray = new byte[1];
// byteArray[0] = message;
new WriteToServerTask().execute(message);
}
@Override
public void onResume() {
super.onResume();
}
@Override
public void onPause() {
super.onPause();
sendToServer("bye."); // defined in server that this string terminates
// connection
new CloseSocketTask().execute();
}
CommsThread 类：
package com.example.paradroid;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import android.util.Log;
import java.io.PrintWriter;
public class CommsThread extends Thread {
private final Socket socket;
private final InputStream inputStream;
private final OutputStream outputStream;
private final PrintWriter out;
public CommsThread(Socket sock) throws IOException {
socket = sock;
InputStream tmpIn = null;
OutputStream tmpOut = null;
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.d("SocketChat", e.getLocalizedMessage());
}
inputStream = tmpIn;
outputStream = tmpOut;
out = new PrintWriter(sock.getOutputStream(), true);
}
public void run() {
}
public void write(String bytes) {
out.println(bytes);
}
public void cancel() {
try {
socket.close();
} catch (IOException e) {
}
}
}