问题
I have Wi-fi direct demo. In that we can transfer any image files to other devices. When another device get connected and it shows to send image from gallery. And at other side it shows sent image. But I want to send a simple string and at other side I want to toast that string. Here I am posting a code in which they have implemented file transfer. I am very confused in this code. I am not getting where to change to pass only string. Please help me. Thanks.
DeviceDetailFragment.java
/**
* A fragment that manages a particular peer and allows interaction with device
* i.e. setting up network connection and transferring data.
*/
public class DeviceDetailFragment extends Fragment implements ConnectionInfoListener {
protected static final int CHOOSE_FILE_RESULT_CODE = 20;
private View mContentView = null;
private WifiP2pDevice device;
private WifiP2pInfo info;
ProgressDialog progressDialog = null;
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
mContentView = inflater.inflate(R.layout.device_detail, null);
mContentView.findViewById(R.id.btn_connect).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
WifiP2pConfig config = new WifiP2pConfig();
config.deviceAddress = device.deviceAddress;
config.wps.setup = WpsInfo.PBC;
if (progressDialog != null && progressDialog.isShowing()) {
progressDialog.dismiss();
}
progressDialog = ProgressDialog.show(getActivity(), "Press back to cancel",
"Connecting to :" + device.deviceAddress, true, true
// new DialogInterface.OnCancelListener() {
//
// @Override
// public void onCancel(DialogInterface dialog) {
// ((DeviceActionListener) getActivity()).cancelDisconnect();
// }
// }
);
((DeviceActionListener) getActivity()).connect(config);
}
});
mContentView.findViewById(R.id.btn_disconnect).setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
((DeviceActionListener) getActivity()).disconnect();
}
});
mContentView.findViewById(R.id.btn_start_client).setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
// Allow user to pick an image from Gallery or other
// registered apps
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, CHOOSE_FILE_RESULT_CODE);
}
});
return mContentView;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
// User has picked an image. Transfer it to group owner i.e peer using
// FileTransferService.
Uri uri = data.getData();
TextView statusText = (TextView) mContentView.findViewById(R.id.status_text);
statusText.setText("Sending: " + uri);
Log.d(WiFiDirectActivity.TAG, "Intent----------- " + uri);
Intent serviceIntent = new Intent(getActivity(), FileTransferService.class);
serviceIntent.setAction(FileTransferService.ACTION_SEND_FILE);
serviceIntent.putExtra(FileTransferService.EXTRAS_FILE_PATH, uri.toString());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_ADDRESS,
info.groupOwnerAddress.getHostAddress());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_PORT, 8988);
getActivity().startService(serviceIntent);
}
@Override
public void onConnectionInfoAvailable(final WifiP2pInfo info) {
if (progressDialog != null && progressDialog.isShowing()) {
progressDialog.dismiss();
}
this.info = info;
this.getView().setVisibility(View.VISIBLE);
// The owner IP is now known.
TextView view = (TextView) mContentView.findViewById(R.id.group_owner);
view.setText(getResources().getString(R.string.group_owner_text)
+ ((info.isGroupOwner == true) ? getResources().getString(R.string.yes)
: getResources().getString(R.string.no)));
// InetAddress from WifiP2pInfo struct.
view = (TextView) mContentView.findViewById(R.id.device_info);
view.setText("Group Owner IP - " + info.groupOwnerAddress.getHostAddress());
// After the group negotiation, we assign the group owner as the file
// server. The file server is single threaded, single connection server
// socket.
if (info.groupFormed && info.isGroupOwner) {
new FileServerAsyncTask(getActivity(), mContentView.findViewById(R.id.status_text))
.execute();
} else if (info.groupFormed) {
// The other device acts as the client. In this case, we enable the
// get file button.
mContentView.findViewById(R.id.btn_start_client).setVisibility(View.VISIBLE);
((TextView) mContentView.findViewById(R.id.status_text)).setText(getResources()
.getString(R.string.client_text));
}
// hide the connect button
mContentView.findViewById(R.id.btn_connect).setVisibility(View.GONE);
}
/**
* Updates the UI with device data
*
* @param device the device to be displayed
*/
public void showDetails(WifiP2pDevice device) {
this.device = device;
this.getView().setVisibility(View.VISIBLE);
TextView view = (TextView) mContentView.findViewById(R.id.device_address);
view.setText(device.deviceAddress);
view = (TextView) mContentView.findViewById(R.id.device_info);
view.setText(device.toString());
}
/**
* Clears the UI fields after a disconnect or direct mode disable operation.
*/
public void resetViews() {
mContentView.findViewById(R.id.btn_connect).setVisibility(View.VISIBLE);
TextView view = (TextView) mContentView.findViewById(R.id.device_address);
view.setText(R.string.empty);
view = (TextView) mContentView.findViewById(R.id.device_info);
view.setText(R.string.empty);
view = (TextView) mContentView.findViewById(R.id.group_owner);
view.setText(R.string.empty);
view = (TextView) mContentView.findViewById(R.id.status_text);
view.setText(R.string.empty);
mContentView.findViewById(R.id.btn_start_client).setVisibility(View.GONE);
this.getView().setVisibility(View.GONE);
}
/**
* A simple server socket that accepts connection and writes some data on
* the stream.
*/
public static class FileServerAsyncTask extends AsyncTask<Void, Void, String> {
private Context context;
private TextView statusText;
/**
* @param context
* @param statusText
*/
public FileServerAsyncTask(Context context, View statusText) {
this.context = context;
this.statusText = (TextView) statusText;
}
@Override
protected String doInBackground(Void... params) {
try {
ServerSocket serverSocket = new ServerSocket(8988);
Log.d(WiFiDirectActivity.TAG, "Server: Socket opened");
Socket client = serverSocket.accept();
Log.d(WiFiDirectActivity.TAG, "Server: connection done");
final File f = new File(Environment.getExternalStorageDirectory() + "/"
+ context.getPackageName() + "/wifip2pshared-" + System.currentTimeMillis()
+ ".jpg");
File dirs = new File(f.getParent());
if (!dirs.exists())
dirs.mkdirs();
f.createNewFile();
Log.d(WiFiDirectActivity.TAG, "server: copying files " + f.toString());
InputStream inputstream = client.getInputStream();
copyFile(inputstream, new FileOutputStream(f));
serverSocket.close();
return f.getAbsolutePath();
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
return null;
}
}
/*
* (non-Javadoc)
* @see android.os.AsyncTask#onPostExecute(java.lang.Object)
*/
@Override
protected void onPostExecute(String result) {
if (result != null) {
statusText.setText("File copied - " + result);
Intent intent = new Intent();
intent.setAction(android.content.Intent.ACTION_VIEW);
intent.setDataAndType(Uri.parse("file://" + result), "image/*");
context.startActivity(intent);
}
}
/*
* (non-Javadoc)
* @see android.os.AsyncTask#onPreExecute()
*/
@Override
protected void onPreExecute() {
statusText.setText("Opening a server socket");
}
}
public static boolean copyFile(InputStream inputStream, OutputStream out) {
byte buf[] = new byte[1024];
int len;
long startTime=System.currentTimeMillis();
try {
while ((len = inputStream.read(buf)) != -1) {
out.write(buf, 0, len);
}
out.close();
inputStream.close();
long endTime=System.currentTimeMillis()-startTime;
Log.v("","Time taken to transfer all bytes is : "+endTime);
} catch (IOException e) {
Log.d(WiFiDirectActivity.TAG, e.toString());
return false;
}
return true;
}
}
FileTransferService.java
/**
* A service that process each file transfer request i.e Intent by opening a
* socket connection with the WiFi Direct Group Owner and writing the file
*/
public class FileTransferService extends IntentService {
private static final int SOCKET_TIMEOUT = 5000;
public static final String ACTION_SEND_FILE = "com.example.android.wifidirect.SEND_FILE";
public static final String EXTRAS_FILE_PATH = "file_url";
public static final String EXTRAS_GROUP_OWNER_ADDRESS = "go_host";
public static final String EXTRAS_GROUP_OWNER_PORT = "go_port";
public FileTransferService(String name) {
super(name);
}
public FileTransferService() {
super("FileTransferService");
}
/*
* (non-Javadoc)
* @see android.app.IntentService#onHandleIntent(android.content.Intent)
*/
@Override
protected void onHandleIntent(Intent intent) {
Context context = getApplicationContext();
if (intent.getAction().equals(ACTION_SEND_FILE)) {
String fileUri = intent.getExtras().getString(EXTRAS_FILE_PATH);
String host = intent.getExtras().getString(EXTRAS_GROUP_OWNER_ADDRESS);
Socket socket = new Socket();
int port = intent.getExtras().getInt(EXTRAS_GROUP_OWNER_PORT);
try {
Log.d(WiFiDirectActivity.TAG, "Opening client socket - ");
socket.bind(null);
socket.connect((new InetSocketAddress(host, port)), SOCKET_TIMEOUT);
Log.d(WiFiDirectActivity.TAG, "Client socket - " + socket.isConnected());
OutputStream stream = socket.getOutputStream();
ContentResolver cr = context.getContentResolver();
InputStream is = null;
try {
is = cr.openInputStream(Uri.parse(fileUri));
} catch (FileNotFoundException e) {
Log.d(WiFiDirectActivity.TAG, e.toString());
}
DeviceDetailFragment.copyFile(is, stream);
Log.d(WiFiDirectActivity.TAG, "Client: Data written");
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
} finally {
if (socket != null) {
if (socket.isConnected()) {
try {
socket.close();
} catch (IOException e) {
// Give up
e.printStackTrace();
}
}
}
}
}
}
}
回答1:
You can do something like this:
DeviceDetailFragment.java
@Override
protected String doInBackground(Void... params) {
ServerSocket serverSocket = null;
Socket client = null;
DataInputStream inputstream = null;
try {
serverSocket = new ServerSocket(8988);
client = serverSocket.accept();
inputstream = new DataInputStream(client.getInputStream());
String str = inputstream.readUTF();
serverSocket.close();
return str;
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
return null;
}finally{
if(inputstream != null){
try{
inputstream.close();
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
}
}
if(client != null){
try{
client.close();
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
}
}
if(serverSocket != null){
try{
serverSocket.close();
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
}
}
}
}
@Override
protected void onPostExecute(String result) {
if (result != null) {
Toast.makeText(..., result, ...).show();;
}
}
FileTransferService.java
@Override
protected void onHandleIntent(Intent intent) {
Context context = getApplicationContext();
if (intent.getAction().equals(ACTION_SEND_FILE)) {
String host = intent.getExtras().getString(EXTRAS_GROUP_OWNER_ADDRESS);
Socket socket = new Socket();
int port = intent.getExtras().getInt(EXTRAS_GROUP_OWNER_PORT);
DataOutputStream stream = null;
try {
socket.connect((new InetSocketAddress(host, port)), SOCKET_TIMEOUT);
stream = new DataOutputStream(socket.getOutputStream());
stream.writeUTF("a string");
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
} finally {
if (stream != null) {
try {
stream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (socket != null) {
if (socket.isConnected()) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
}
来源：https://stackoverflow.com/questions/28914774/android-passing-simple-string-over-wi-fi