本文介绍了Android-通过套接字编程发送图像的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在实现一个套接字应用程序，其中一个电话将成为客户端，而另一部电话将成为服务器.该程序能够使用打印书写器从客户端向服务器发送字符串，但是当我尝试发送图像文件时，它将引发异常.如果有人可以帮助我，我将非常感激.
I am implementing a socket application where one phone will be a client and the other will be a server. The program is able to send strings using print writer just fine from the client to the sever but when i try to send an image file, it throws an exception. I'd really appreciate if someone could help me out.
这是服务器的代码
public class ServerActivity extends Activity {
private TextView serverStatus;
private ImageView profile;
// DEFAULT IP
public static String SERVERIP = "10.0.2.15";
// DESIGNATE A PORT
public static final int SERVERPORT = 8080;
private Handler handler = new Handler();
private ServerSocket serverSocket;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.server);
serverStatus = (TextView) findViewById(R.id.server_status);
profile = (ImageView) findViewById(R.id.image);
String filepath = "/sdcard/DCIM/time table.png";
File imagefile = new File(filepath);
FileInputStream fis = null;
try {
fis = new FileInputStream(imagefile);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Bitmap bm = BitmapFactory.decodeStream(fis);
profile.setImageBitmap(bm);
SERVERIP = getLocalIpAddress();
Thread fst = new Thread(new ServerThread());
fst.start();
}
public class ServerThread implements Runnable {
//String line;
byte [] line;
Bitmap bitmap;
public void run() {
try {
if (SERVERIP != null) {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Listening on IP: " + SERVERIP);
}
});
serverSocket = new ServerSocket(SERVERPORT);
while (true) {
// LISTEN FOR INCOMING CLIENTS
Socket client = serverSocket.accept();
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Connected.");
}
});
try {
/*InputStream in = client.getInputStream();
line = null;
in.read(line);
Log.d("ServerActivity", line.toString());
bitmap = BitmapFactory.decodeByteArray(line , 0, line.length);*/
int bytesRead;
int current = 0;
int filesize=65383;
byte [] mybytearray2 = new byte [filesize];
InputStream is = client.getInputStream();
FileOutputStream fos = new FileOutputStream("/storage/sdcard0/Pictures/Screenshots/IMG-20130112-WA0011.jpeg"); // destination path and name of file
//FileOutputStream fos = new FileOutputStream("/storage/sdcard0/Pictures/Screenshots/");
BufferedOutputStream bos = new BufferedOutputStream(fos);
bytesRead = is.read(mybytearray2,0,mybytearray2.length);
current = bytesRead;
do {
bytesRead =
is.read(mybytearray2, current, (mybytearray2.length-current));
if(bytesRead >= 0) current += bytesRead;
} while(bytesRead > -1);
bos.write(mybytearray2, 0 , current);
bos.flush();
long end = System.currentTimeMillis();
//System.out.println(end-start);
bos.close();
handler.post(new Runnable() {
@Override
public void run() {
profile.setImageBitmap(bitmap);
//serverStatus.setText(line);
}
});
/*BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));
line = null;
while ((line = in.readLine()) != null) {
Log.d("ServerActivity", line);
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText(line);
// DO WHATEVER YOU WANT TO THE FRONT END
// THIS IS WHERE YOU CAN BE CREATIVE
}
});
}*/
break;
} catch (Exception e) {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Oops. Connection interrupted. Please reconnect your phones.");
}
});
e.printStackTrace();
}
}
} else {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Couldn't detect internet connection.");
}
});
}
} catch (Exception e) {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Error");
}
});
e.printStackTrace();
}
}
}
// GETS THE IP ADDRESS OF YOUR PHONE'S NETWORK
private String getLocalIpAddress() {
try {
for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {
NetworkInterface intf = en.nextElement();
for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {
InetAddress inetAddress = enumIpAddr.nextElement();
if (!inetAddress.isLoopbackAddress()) { return inetAddress.getHostAddress().toString(); }
}
}
} catch (SocketException ex) {
Log.e("ServerActivity", ex.toString());
}
return null;
}
@Override
protected void onStop() {
super.onStop();
try {
// MAKE SURE YOU CLOSE THE SOCKET UPON EXITING
serverSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
这是客户端代码
public class ClientActivity extends Activity {
private EditText serverIp;
private Button connectPhones;
private String serverIpAddress = "";
private boolean connected = false;
private Handler handler = new Handler();
private Socket socket;
private ImageView profile;
private byte [] imgbyte;
String filepath;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.client);
serverIp = (EditText) findViewById(R.id.server_ip);
connectPhones = (Button) findViewById(R.id.connect_phones);
connectPhones.setOnClickListener(connectListener);
profile = (ImageView) findViewById(R.id.imageView1);
filepath = "/sdcard/small.jpg";
File imagefile = new File(filepath);
FileInputStream fis = null;
try {
fis = new FileInputStream(imagefile);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Bitmap bm = BitmapFactory.decodeStream(fis);
imgbyte = getBytesFromBitmap(bm);
profile.setImageBitmap(bm);
}
private OnClickListener connectListener = new OnClickListener() {
@Override
public void onClick(View v) {
if (!connected) {
serverIpAddress = serverIp.getText().toString();
if (!serverIpAddress.equals("")) {
Thread cThread = new Thread(new ClientThread());
cThread.start();
}
}
}
};
public class ClientThread implements Runnable {
public void run() {
try {
InetAddress serverAddr = InetAddress.getByName(serverIpAddress);
Log.d("ClientActivity", "C: Connecting...");
socket = new Socket(serverAddr, ServerActivity.SERVERPORT);
connected = true;
while (connected) {
try {
/*File myFile = new File (filepath);
byte [] mybytearray = new byte [(int)myFile.length()];
FileInputStream fis = new FileInputStream(myFile);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray,0,mybytearray.length);
OutputStream os = socket.getOutputStream();
Log.d("ClientActivity", "C: Sending command.");
//System.out.println("Sending...");
os.write(mybytearray,0,mybytearray.length);
os.flush();*/
Log.d("ClientActivity", "C: Sending command.");
/*PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket
.getOutputStream())), true);*/
// WHERE YOU ISSUE THE COMMANDS
OutputStream output = socket.getOutputStream();
Log.d("ClientActivity", "C: image writing.");
output.write(imgbyte);
output.flush();
// out.println("Hey Server!");
Log.d("ClientActivity", "C: Sent.");
} catch (Exception e) {
Log.e("ClientActivity", "S: Error", e);
}
}
socket.close();
Log.d("ClientActivity", "C: Closed.");
} catch (Exception e) {
Log.e("ClientActivity", "C: Error", e);
connected = false;
}
}
}
protected void onStop() {
super.onStop();
try {
// MAKE SURE YOU CLOSE THE SOCKET UPON EXITING
socket.close();
connected = false;
} catch (IOException e) {
e.printStackTrace();
}
}
public byte[] getBytesFromBitmap(Bitmap bitmap) {
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(CompressFormat.JPEG, 70, stream);
return stream.toByteArray();
}
}
更新:服务器端代码抛出异常.它的异常显示为:糟糕.连接中断.请重新连接手机."这是抛出的异常:java.lang.RuntimeException:无法在尚未调用Looper.prepare()的线程内创建处理程序
update:The exception is thrown at the server side code. Its the exception which reads :"Oops. Connection interrupted. Please reconnect your phones."This is the exception that is thrown:java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
推荐答案
谢谢大家，我发现了错误.敬酒消息必须位于UI线程或处理程序内.由于我在非UI线程中有其中一些，所以它开始引发异常.
Thanks everyone , I found the error.The toast messages have to be inside the UI thread or the handler . As I had a few of them in a non UI thread, it began to throw the exception.
这篇关于Android-通过套接字编程发送图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！