本文介绍了难点在连接到远程设备。需要多次尝试的处理方法，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
我的工作有一个项目，我需要连接我的平板电脑（安卓4.2.2），蓝牙至UART转换器（RN42由微芯片）。我使用BluetoothChat例如管理蓝牙连接，但其难以连接。有时在程序法mmSocket.connect失败（）; - 它抛出IOException异常。有时候，我需要三个或更多的尝试连接到我的远程设备。由连接之后，它是非常稳定的。我试图改变UUID，试图改变rn42模块（我还试图用HC-05模块）。我试过安全和不安全的RFCOMM连接，仍然没有运气。这里是我的code：在MainActivity：
I working with a project where I need to connect my tablet (android 4.2.2) to Bluetooth-to-UART converter (RN42 by microchip).I am using BluetoothChat example to manage bluetooth connection, but its difficult to connect. Sometimes program fails at method mmSocket.connect(); - it throws IOException. Sometimes i need three or more tries to connect to my remote device. After connection is made, it is very stable.I tried to change UUID, tried to change rn42 module (i also tried to use HC-05 module).I tried secure and insecure rfcomm connection, still no luck.here is my code:In the MainActivity:
@Override
public void onButtonPressed(View view, Device device){
switch (view.getId()){
case R.id.buttonRedaguotiIrengini:
// Edit button is pressed
Intent i = new Intent(this, DeviceActivity.class);
i.putExtra("device", device);
i.putExtra("requestCode", REQUEST_EDIT_DEVICE);
startActivityForResult(i, REQUEST_EDIT_DEVICE);
break;
case R.id.buttonPrisijungti:
if (mBtService.getState()==BluetoothService.STATE_CONNECTED){
mBtService.stop();
} else {
BluetoothDevice btDevice = mBluetoothAdapter.getRemoteDevice(device.getMac());
mBtService.connect(btDevice, false);
}
break;
}
}
在BluetoothService类：
in the BluetoothService Class:
// Name for the SDP record when creating server socket
private static final String NAME_SECURE = "BluetoothChatSecure";
private static final String NAME_INSECURE = "BluetoothChatInsecure";
// Unique UUID for this application
private static final UUID MY_UUID_SECURE =UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
private static final UUID MY_UUID_INSECURE = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private AcceptThread mSecureAcceptThread;
private AcceptThread mInsecureAcceptThread;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private int mState;
// Constants that indicate the current connection state
public static final int STATE_NONE = 0; // we're doing nothing
public static final int STATE_LISTEN = 1; // now listening for incoming connections
public static final int STATE_CONNECTING = 2; // now initiating an outgoing connection
public static final int STATE_CONNECTED = 3; // now connected to a remote device
public synchronized void connect(BluetoothDevice device, boolean secure) {
if (D) Log.d(TAG, "connect to: " + device);
// Cancel any thread attempting to make a connection
if (mState == STATE_CONNECTING) {
if (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}
}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}
// Start the thread to connect with the given device
mConnectThread = new ConnectThread(device, secure);
mConnectThread.start();
setState(STATE_CONNECTING);
}
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
private String mSocketType;
public ConnectThread(BluetoothDevice device, boolean secure) {
mmDevice = device;
BluetoothSocket tmp = null;
mSocketType = secure ? "Secure" : "Insecure";
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
if (secure) {
tmp = device.createRfcommSocketToServiceRecord(
MY_UUID_SECURE);
} else {
tmp = device.createInsecureRfcommSocketToServiceRecord(
MY_UUID_INSECURE);
}
} catch (IOException e) {
Log.e(TAG, "Socket Type: " + mSocketType + "create() failed", e);
}
mmSocket = tmp;
}
public void run() {
Log.i(TAG, "BEGIN mConnectThread SocketType:" + mSocketType);
setName("ConnectThread" + mSocketType);
// Always cancel discovery because it will slow down a connection
mAdapter.cancelDiscovery();
// Make a connection to the BluetoothSocket
try {
// This is a blocking call and will only return on a
// successful connection or an exception
if (D) {Log.d(TAG, "will try to connect to socket");};
mmSocket.connect();
} catch (IOException e) {
// Close the socket
if (D) {Log.d(TAG, "failed to connect to socket");};
e.printStackTrace();
try {
mmSocket.close();
} catch (IOException e2) {
Log.e(TAG, "unable to close() " + mSocketType +
" socket during connection failure", e2);
}
connectionFailed();
return;
}
if (D){Log.d(TAG, "Success");};
// Reset the ConnectThread because we're done
synchronized (BluetoothService.this) {
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket, mmDevice, mSocketType);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect " + mSocketType + " socket failed", e);
}
}
}
private void connectionFailed() {
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(MainActivity.TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
if (D){Log.d(TAG, "Failed, unable to connect device");};
setState(STATE_NONE);
}
下面是LogCat中输出
Here are the LogCat output
03-12 16:01:38.992: D/mBT(9947): connect to: 00:06:66:67:44:3E
03-12 16:01:38.992: I/BluetoothSocket_MTK(9947): [JSR82] Bluetooth Socket Constructor
03-12 16:01:38.992: I/BluetoothSocket_MTK(9947): [JSR82] type=1 fd=-1 auth=false encrypt=false port=-1
03-12 16:01:38.993: D/BTSocketService(452): [JSR82][Service] initSocket
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] initSocketNative +++.
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] initSocketNative: start to initialize socket.
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] type=1, auth=0, encrypt=0, port=-1
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] initSocketNative: Initialize socket done.
03-12 16:01:38.993: E/BluetoothSocketService.cpp(452): [JSR82] alloc context : index=2
03-12 16:01:38.993: E/BluetoothSocketService.cpp(452): [JSR82] Clear context : index=2, ctx.index=0, ctx.fd=0
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] jsr82ConnectCond (2) initialization success
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] jsr82ReadCond (2) initialization success <READ>
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] jsr82WriteCond (2) initialization success <WRITE>
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] jsr82RegisterCond (2) initialization success <REGISTER>
03-12 16:01:38.993: I/BluetoothSocketService.cpp(452): [JSR82][JNI] initSocketNative ---. fdHandle=32770
03-12 16:01:38.995: D/mBT(9947): setState() 1 -> 2
03-12 16:01:38.998: I/mBT(9947): BEGIN mConnectThread SocketType:Insecure
03-12 16:01:39.001: D/BluetoothService(452): [API] cancelDiscovery()
03-12 16:01:39.001: I/BluetoothService.cpp(452): [GAP][API] stopDiscoveryNative
03-12 16:01:39.001: I/BluetoothService.cpp(452): [GAP] btmtk_gap_discovery_cancel
03-12 16:01:39.001: I/BluetoothService.cpp(452): [GAP] btmtk_gap_discovery_cancel already cancelled
03-12 16:01:39.001: I/BluetoothService.cpp(452): [GAP] btmtk_gap_send_discovery_stop_event
03-12 16:01:39.001: I/BluetoothService.cpp(452): [JNI] bt_sendind(ptr=0x5C6AEA50, len=28)
03-12 16:01:39.001: I/BluetoothService.cpp(452): [JNI] send ind=3528
03-12 16:01:39.001: I/BluetoothEventLoop.cpp(452): [MSG] Polling returned
03-12 16:01:39.001: I/BluetoothEventLoop.cpp(452): [MSG] Start retrieve data
03-12 16:01:39.002: I/BluetoothEventLoop.cpp(452): [MSG] fd 1 data ready
03-12 16:01:39.002: I/BluetoothEventLoop.cpp(452): [MSG] nat->pollData[i].fd data ready : revents = 0x1
03-12 16:01:39.002: I/BluetoothEventLoop.cpp(452): [MSG] msg 3528 received : size=28
03-12 16:01:39.002: I/BluetoothEventLoop.cpp(452): [GAP] receive event=3528
03-12 16:01:39.002: I/BluetoothEventLoop.cpp(452): [GAP] btmtk_util_update_adapter_property_discovering: is_discovering = 0
03-12 16:01:39.002: D/BluetoothEventLoop(452): Property Changed: Discovering : false
03-12 16:01:39.006: I/BluetoothService.cpp(452): [JNI] send ind success : 28
03-12 16:01:39.007: I/BluetoothEventLoop.cpp(452): [MSG] Start polling
03-12 16:01:39.008: V/BluetoothEventManager(1562): Received android.bluetooth.adapter.action.DISCOVERY_FINISHED
03-12 16:01:39.011: D/mBT(9947): will try to connect to socket
03-12 16:01:39.011: I/BluetoothSocket_MTK(9947): [JSR82] connect: do SDP
03-12 16:01:39.012: D/BluetoothService(452): [API] fetchRemoteUuids(00:06:66:67:44:3E)
03-12 16:01:39.012: V/BluetoothAdapterProperties(452): getObjectPath():MTKBT/dev_
03-12 16:01:39.012: I/BluetoothService.cpp(452): [GAP][API] discoverServicesNative : addr=MTKBT/dev_00_06_66_67_44_3E, pattern=00001101-0000-1000-8000-00805f9b34fb
03-12 16:01:39.013: I/BluetoothService.cpp(452): [GAP] btmtk_gap_service_search_raw_request addr=67443E:66:6, size=19
03-12 16:01:39.013: D/[BT](142): mtk_bt_write: buffer bebcbcc8, len 5
03-12 16:01:39.013: I/BluetoothService.cpp(452): [GAP] btmtk_gap_send_sdp_discover_event
03-12 16:01:39.013: I/BluetoothService.cpp(452): [JNI] bt_sendind(ptr=0x54B921A0, len=60)
03-12 16:01:39.013: I/BluetoothService.cpp(452): [JNI] send ind=3535
03-12 16:01:39.013: I/BluetoothService.cpp(452): [JNI] send ind success : 60
03-12 16:01:39.013: I/BluetoothEventLoop.cpp(452): [MSG] Polling returned
03-12 16:01:39.013: I/BluetoothEventLoop.cpp(452): [MSG] Start retrieve data
03-12 16:01:39.013: I/BluetoothEventLoop.cpp(452): [MSG] fd 1 data ready
03-12 16:01:39.014: I/BluetoothEventLoop.cpp(452): [MSG] nat->pollData[i].fd data ready : revents = 0x1
03-12 16:01:39.014: I/BluetoothEventLoop.cpp(452): [MSG] msg 3535 received : size=60
03-12 16:01:39.014: I/BluetoothEventLoop.cpp(452): [GAP] receive event=3535
03-12 16:01:39.014: I/BluetoothEventLoop.cpp(452): [GAP] receive event ANDROID_EV_SDP_DEVICE_CREATE 0x67443E:0x66:0x6
03-12 16:01:39.014: I/BluetoothEventLoop.cpp(452): [GAP] pattern (16) 0: 0:11: 1
03-12 16:01:39.014: I/BluetoothEventLoop.cpp(452): [MSG] Start polling
03-12 16:01:39.015: V/BluetoothDiscoveryReceiver(1562): Received: android.bluetooth.adapter.action.DISCOVERY_FINISHED
03-12 16:01:39.018: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:39.018: D/[BT](142): mtk_bt_read: buffer 401c9024, len 2
03-12 16:01:39.018: D/[BT](142): mtk_bt_read: buffer 401980e6, len 4
03-12 16:01:39.018: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:39.019: D/[BT](142): mtk_bt_write: buffer bebcbcc8, len 5
03-12 16:01:39.026: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:39.026: D/[BT](142): mtk_bt_read: buffer 401c9024, len 2
03-12 16:01:39.026: D/[BT](142): mtk_bt_read: buffer 401981e7, len 4
03-12 16:01:39.026: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:39.026: D/[BT](142): mtk_bt_write: buffer bebcbcc8, len 17
03-12 16:01:39.032: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:39.032: D/[BT](142): mtk_bt_read: buffer 401c9024, len 2
03-12 16:01:39.032: D/[BT](142): mtk_bt_read: buffer 401982e8, len 4
03-12 16:01:39.033: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:40.017: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:40.017: D/[BT](142): mtk_bt_read: buffer 401c9024, len 2
03-12 16:01:40.017: D/[BT](142): mtk_bt_read: buffer 401983e9, len 4
03-12 16:01:40.017: D/[BT](142): mtk_bt_read: buffer 401c901c, len 1
03-12 16:01:44.775: D/Bluetooth HS/HF(692): [BT][HFG] [API] mStateReceiver.onReceive(android.intent.action.BATTERY_CHANGED)
03-12 16:01:44.776: D/Bluetooth HS/HF(692): [BT][HFG] [API] mHandler.handleMessage(9)
03-12 16:01:44.776: D/Bluetooth HS/HF(692): [BT][HFG] [API] updateBatteryState
03-12 16:01:45.014: D/BluetoothService(452): [API] getUuidFromCache(00:06:66:67:44:3E)
03-12 16:01:45.015: D/BluetoothService(452): [API] getUuidFromCache=00001101-0000-1000-8000-00805f9b34fb)
03-12 16:01:45.016: D/BluetoothService(452): [API] getUuidFromCache=00001101-0000-1000-8000-00805f9b34fb)
03-12 16:01:45.016: D/BluetoothService(452): [API] sendUuidIntent(00:06:66:67:44:3E)
03-12 16:01:45.020: D/Bluetooth HSHFP(692): [BT][HFG][Intent] action=android.bluetooth.device.action.UUID, state=0
03-12 16:01:45.022: D/BluetoothService(452): [API] makeServiceChannelCallbacks(00:06:66:67:44:3E)
03-12 16:01:45.022: D/BluetoothService(452): Cleaning up failed UUID channel lookup: 00:06:66:67:44:3E 00001101-0000-1000-8000-00805f9b34fb
03-12 16:01:45.022: I/BluetoothSocket_MTK(9947): [JSR82] SdpHelper::onRfcommChannelFound: channel=-1
03-12 16:01:45.023: D/mBT(9947): failed to connect to socket
03-12 16:01:45.023: W/System.err(9947): java.io.IOException: Service discovery failed
03-12 16:01:45.024: W/System.err(9947): at android.bluetooth.BluetoothSocket$SdpHelper.doSdp(BluetoothSocket.java:813)
03-12 16:01:45.024: W/System.err(9947): at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:382)
03-12 16:01:45.024: W/System.err(9947): at p.demoui.BluetoothService$ConnectThread.run(BluetoothService.java:389)
03-12 16:01:45.024: I/BluetoothSocket_MTK(9947): [JSR82] close
03-12 16:01:45.024: I/BluetoothSocket_MTK(9947): [JSR82] readLock got.
03-12 16:01:45.025: D/BTSocketService(452): [JSR82][Service] abort
03-12 16:01:45.025: I/BluetoothSocketService.cpp(452): [JSR82][JNI] abortNative +++. fd=32770.
03-12 16:01:45.025: I/BluetoothSocketService.cpp(452): [JSR82][JNI] abortNative ---.
03-12 16:01:45.025: I/BluetoothSocket_MTK(9947): [JSR82] Start to aquire writeLock.
03-12 16:01:45.026: I/BluetoothSocket_MTK(9947): [JSR82] writeLock got.
03-12 16:01:45.026: D/BTSocketService(452): [JSR82][Service] destroy
03-12 16:01:45.026: I/BluetoothSocketService.cpp(452): [JSR82][JNI] destroyNative: fd=32770.
03-12 16:01:45.026: E/BluetoothSocketService.cpp(452): [JSR82] Clear context : index=2, ctx.index=-1, ctx.fd=32770
03-12 16:01:45.030: D/mBT(9947): Failed, unable to connect device
03-12 16:01:45.030: D/mBT(9947): setState() 2 -> 0
在哪里是错？我怎样才能改善这种code？为什么则抛出IOException在这种情况下？
Where is mistake? how can I improve this code?Why is the IOException is thrown in this case?
感谢您的帮助。
推荐答案
下面是我如何做了类似的蓝牙连接，并发送commands.I我发布完整的演示code，请不妨一试。
Here is how I had done similar Bluetooth connection and sending commands.I am posting complete demo code please give it a try.
BluetoothService.java （同一类从BluetoothChat例子）
可以在这里找到 http://stanford.edu/~tpurtell/BluetoothChatService.java
BluetoothService.java ( same class from BluetoothChat example)
can be found here http://stanford.edu/~tpurtell/BluetoothChatService.java
在我的情况下MACID已经$给我p $ P。
In My case MacID was already pre given to me.
MainActivity.java
public class MainActivity extends Activity implements OnClickListener {
// Layout Views
private Button bt_on_off;
private TextView statuses;
private Button connectIt;
private Button click;
//Timer timer;
private boolean isBTOnOrOff = false;
// Debugging
private static final String TAG = "BluetoothChat";
private static final boolean D = true;
// Message types sent from the BluetoothChatService Handler
public static final int MESSAGE_STATE_CHANGE = 1;
public static final int MESSAGE_READ = 2;
public static final int MESSAGE_WRITE = 3;
public static final int MESSAGE_DEVICE_NAME = 4;
public static final int MESSAGE_TOAST = 5;
// Key names received from the BluetoothChatService Handler
public static final String DEVICE_NAME = "device_name";
public static final String TOAST = "toast";
// Intent request codes
private static final int REQUEST_CONNECT_DEVICE = 1;
private static final int REQUEST_ENABLE_BT = 2;
// Name of the connected device
private String mConnectedDeviceName = null;
// Array adapter for the conversation thread
//private ArrayAdapter<String> mConversationArrayAdapter;
// String buffer for outgoing messages
private StringBuffer mOutStringBuffer;
// Local Bluetooth adapter
private BluetoothAdapter mBluetoothAdapter = null;
// Member object for the chat services
private BluetoothService mChatService = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
enableDissableViews(false);
listeners();
preBTConfigCheck();
}
private void initViews() {
bt_on_off = (Button) findViewById(R.id.bt_on_off);
connectIt= (Button) findViewById(R.id.connect);
statuses= (TextView) findViewById(R.id.statuses);
click= (Button) findViewById(R.id.click);
}
private void listeners() {
bt_on_off.setOnClickListener(this);
connectIt.setOnClickListener(this);
click.setOnClickListener(this);
}
// Broadcast reciever for BT
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if (action.equals(BluetoothAdapter.ACTION_STATE_CHANGED)) {
final int state = intent.getIntExtra(
BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR);
switch (state) {
case BluetoothAdapter.STATE_OFF:
enableDissableViews(false);
isBTOnOrOff=false;
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "OFF");
if (D)
Log.d(TAG, "STATE OFF");
break;
case BluetoothAdapter.STATE_TURNING_OFF:
enableDissableViews(false);
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "Turning off...");
if (D)
Log.d(TAG, "STATE Turning off...");
break;
case BluetoothAdapter.STATE_ON:
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "ON");
if (D)
Log.d(TAG, "STATE ON");
enableDissableViews(true);
isBTOnOrOff=true;
break;
case BluetoothAdapter.STATE_TURNING_ON:
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "Turning on...");
if (D)
Log.d(TAG, "STATE Turning on...");
break;
}
}
}
};
private void preBTConfigCheck() {
// Register for broadcasts on BluetoothAdapter state change
IntentFilter filter = new IntentFilter(
BluetoothAdapter.ACTION_STATE_CHANGED);
this.registerReceiver(mReceiver, filter);
// Get local Bluetooth adapter
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
// If the adapter is null, then Bluetooth is not supported
if (mBluetoothAdapter == null) {
// Device does not support Bluetooth
Toast.makeText(MainActivity.this,
"BlueTooth Not supported on your device!", 0).show();
bt_on_off.setText(getResources().getString(R.string.on_off_status)
+ "NOT SUPPORTED");
enableDissableViews(false);
} else {
// status of BT
isBTOnOrOff = mBluetoothAdapter.isEnabled();
if (D)
Log.d(TAG, "BT status @ preBTConfigCheck() ->" + isBTOnOrOff);
if (isBTOnOrOff) {
// Bluetooth is enable,
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "ON");
enableDissableViews(isBTOnOrOff);
} else {
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "OFF");
// User did not enable Bluetooth or an error occurred
if (D)
Log.d(TAG, "BT not enabled");
enableDissableViews(isBTOnOrOff);
}
}
}
@Override
public void onStart() {
super.onStart();
if(D) Log.e(TAG, "++ ON START ++");
// If BT is not on, request that it be enabled.
// setupChat() will then be called during onActivityResult
if (!mBluetoothAdapter.isEnabled()) {
Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
// Otherwise, setup the chat session
} else {
if (mChatService == null) setupCommand();
}
}
@Override
public synchronized void onResume() {
super.onResume();
if(D) Log.e(TAG, "+ ON RESUME +");
// Performing this check in onResume() covers the case in which BT was
// not enabled during onStart(), so we were paused to enable it...
// onResume() will be called when ACTION_REQUEST_ENABLE activity returns.
if (mChatService != null) {
// Only if the state is STATE_NONE, do we know that we haven't started already
if (mChatService.getState() == BluetoothService.STATE_NONE) {
// Start the Bluetooth chat services
mChatService.start();
}
}
}
@Override
public synchronized void onPause() {
super.onPause();
if(D) Log.e(TAG, "- ON PAUSE -");
}
@Override
public void onStop() {
super.onStop();
if(D) Log.e(TAG, "-- ON STOP --");
}
@Override
public void onDestroy() {
super.onDestroy();
// Stop the Bluetooth chat services
if (mChatService != null) mChatService.stop();
this.unregisterReceiver(mReceiver);
if(D) Log.e(TAG, "--- ON DESTROY ---");
}
private void setupCommand() {
Log.d(TAG, "setupChat()");
// Initialize the BluetoothService to perform bluetooth connections
mChatService = new BluetoothService(this, mHandler);
// Initialize the buffer for outgoing messages
mOutStringBuffer = new StringBuffer("");
}
private void resultMacId(String address) {
// Performing this check in onResume() covers the case in which BT was
// not enabled during onStart(), so we were paused to enable it...
// onResume() will be called when ACTION_REQUEST_ENABLE activity returns.
if (mChatService != null) {
// Only if the state is STATE_NONE, do we know that we haven't started already
if (mChatService.getState() == BluetoothService.STATE_NONE) {
// Start the Bluetooth chat services
mChatService.start();
}
}
// Get the BLuetoothDevice object
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
// Attempt to connect to the device
mChatService.connect(device, false);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item)
{
switch (item.getItemId())
{
case R.id.action_settings:
// Launch the DeviceListActivity to see devices and do scan
return true;
}
return false;
}
// The Handler that gets information back from the BluetoothChatService
private final Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_STATE_CHANGE:
if(D) Log.i(TAG, "MESSAGE_STATE_CHANGE: " + msg.arg1);
switch (msg.arg1) {
case BluetoothService.STATE_CONNECTED:
statuses.setText("connected to :"+mConnectedDeviceName);
// mTitle.setText(R.string.title_connected_to);
//mTitle.append(mConnectedDeviceName);
//mConversationArrayAdapter.clear();
break;
case BluetoothService.STATE_CONNECTING:
statuses.setText("connecting ... ");
// mTitle.setText(R.string.title_connecting);
break;
case BluetoothService.STATE_LISTEN:
case BluetoothService.STATE_NONE:
statuses.setText("Not Connected");
// mTitle.setText(R.string.title_not_connected);
break;
}
break;
case MESSAGE_WRITE:
byte[] writeBuf = (byte[]) msg.obj;
// construct a string from the buffer
String writeMessage = new String(writeBuf);
Log.d(TAG, "MESSAGE_WRITE++++++++"+writeMessage);
//mConversationArrayAdapter.add("Me: " + writeMessage);
break;
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
String readMessage = new String(readBuf, 0, msg.arg1);
Log.d(TAG, "MESSAGE_READ++++++++"+readMessage);
// mConversationArrayAdapter.add(mConnectedDeviceName+": " + readMessage);
break;
case MESSAGE_DEVICE_NAME:
// save the connected device's name
mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);
statuses.setText("Connected to "+ mConnectedDeviceName);
Toast.makeText(getApplicationContext(), "Connected to "
+ mConnectedDeviceName, Toast.LENGTH_SHORT).show();
connectIt.setText("Connected to "+ mConnectedDeviceName);
connectIt.setEnabled(false);
break;
case MESSAGE_TOAST:
statuses.setText(msg.getData().getString(TOAST));
Toast.makeText(getApplicationContext(), msg.getData().getString(TOAST),
Toast.LENGTH_SHORT).show();
break;
}
}
};
/**
* Sends a message.
* @param message A string of text to send.
*/
private void sendMessage(byte[] message) {
// Check that we're actually connected before trying anything
if (mChatService.getState() != BluetoothService.STATE_CONNECTED) {
Toast.makeText(this, "not_connected", Toast.LENGTH_SHORT).show();
return;
}
// Check that there's actually something to send
if (message.length > 0) {
// Get the message bytes and tell the BluetoothChatService to write
mChatService.write(message);
// Reset out string buffer to zero and clear the edit text field
//mOutStringBuffer.setLength(0);
//mOutEditText.setText(mOutStringBuffer);
}
}
private void btOnOffClick() {
if (D)
Log.d(TAG, "BT status @ btOnOffClick() ->" + isBTOnOrOff);
if (isBTOnOrOff) {
// make BT off & set isBTOnOrOff to false
btOFF();
isBTOnOrOff = false;
} else if (!isBTOnOrOff) {
// make BT on & set isBTOnOrOff to true
btON(REQUEST_ENABLE_BT);
isBTOnOrOff = true;
}
}
private void btOFF() {
enableDissableViews(false);
if (D)
Log.d(TAG, "BT status @ btOFF() -> OFF");
mBluetoothAdapter.disable();
bt_on_off.setText(getResources().getString(R.string.on_off_status)
+ "OFF");
}
private void btON(int requestType) {
if (D)
Log.d(TAG, "BT status @ btON() -> Turning on dialog");
Intent enableBtIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, requestType);
}
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (D)
Log.d(TAG, "onActivityResult " + resultCode);
switch (requestCode) {
case REQUEST_ENABLE_BT:
// When the request to enable Bluetooth returns
if (resultCode == Activity.RESULT_OK) {
// Bluetooth is now enabled,
isBTOnOrOff=true;
enableDissableViews(true);
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "ON");
if (D)
Log.d(TAG, "onActivityResult - status ON ");
} else {
isBTOnOrOff=false;
enableDissableViews(false);
bt_on_off.setText(getResources().getString(
R.string.on_off_status)
+ "OFF");
if (D)
Log.d(TAG, "onActivityResult - BT not enabled");
// User did not enable Bluetooth or an error occurred
}
}
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.bt_on_off:
if (D)
Log.d(TAG, "...........ON OFF button clicked ........ ");
// check for BT adaptor available then check its on or off
try {
if (D)
Log.d(TAG, "Before sleep");
// Thread.sleep(SLEEP_THREAD_FOR_ACTION);
if (D)
Log.d(TAG, "after sleep");
btOnOffClick();
if (D)
Log.d(TAG, "after btn click completed");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
break;
case R.id.connect:
resultMacId("00:08:F4:00:12:A4");
break;
case R.id.click:
sendMessage("commands in bytes".getBytes());
break;
default:
break;
}
}
private void disconnectIt() {
if (mChatService != null) mChatService.stop();
connectIt.setEnabled(true);
}
void enableDissableViews(boolean state)
{
if (!state) {
connectIt.setText("Not Connected");
}
connectIt.setEnabled(state);
}
}
activity_main.xml
<LinearLayout
android:id="@+id/top"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:background="#bababa"
android:gravity="center" >
<Button
android:id="@+id/bt_on_off"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:layout_weight="1"
android:text="@string/on_off_status" />
<TextView
android:id="@+id/statuses"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:text="@string/all_status"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#FF0000" />
<Button
android:id="@+id/connect"
style="?android:attr/buttonStyleSmall"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:layout_weight="1"
android:text="@string/socket_connected_status" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/top"
android:layout_weight="1" >
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" >
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" >
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" >
</LinearLayout>
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/TextView01"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:gravity="center"
android:text="GPS"
android:textAppearance="?android:attr/textAppearanceLarge"
android:visibility="gone" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="@+id/click"
android:layout_width="317dp"
android:layout_height="match_parent"
android:text="Send" />
</LinearLayout>
</LinearLayout>
这篇关于难点在连接到远程设备。需要多次尝试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！