我正在使用MainActivity进行蓝牙连接以及通过它发送和接收消息，每个消息都有不同的线程。 现在我从这个活动启动一个片段，在该片段中我通过使用MainActivity代码发送消息将字符串发送到主要活动但是我的UI在执行此操作时挂起了.. 任何人都可以帮助我克服这个问题。 这是我的MainActivity代码：
public class MainActivity extends AppCompatActivity
implements NavigationDrawerFragment.NavigationDrawerCallbacks {
/**
* Fragment managing the behaviors, interactions and presentation of the navigation drawer.
*/
private NavigationDrawerFragment mNavigationDrawerFragment;
/**
* Used to store the last screen title. For use in {@link #restoreActionBar()}.
*/
private CharSequence mTitle;
String address = null;
BluetoothAdapter myBluetoothadpt = null;
BluetoothSocket btSocket = null;
private boolean isBtConnected = false;
static final UUID myUUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
BluetoothDevice device=null;
static ConnectedThread manageConnectedSocket;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
myBluetoothadpt = BluetoothAdapter.getDefaultAdapter();
setContentView(R.layout.activity_main);
mNavigationDrawerFragment = (NavigationDrawerFragment)
getSupportFragmentManager().findFragmentById(R.id.navigation_drawer);
mTitle = getTitle();
// Set up the drawer.
mNavigationDrawerFragment.setUp(
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout));
// myBluetoothadpt = BluetoothAdapter.getDefaultAdapter();
// device = myBluetoothadpt.getRemoteDevice("98:D3:31:20:7F:FB");
// ConnectThread ct = new ConnectThread(device);
// ct.start();
}
@Override
protected void onResume() {
super.onResume();
if (!myBluetoothadpt.isEnabled()) {
Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableIntent,1);
}
}
public static void sendMessage(String s){
Log.d("track", "sendMessage ");
manageConnectedSocket.write(s.getBytes());
}
@Override
public void onNavigationDrawerItemSelected(int position) {
Fragment myFragment=null;
switch (position){
case 0:
myFragment=new Home();
break;
case 1:
myFragment=new Hall();
break;
case 2:
myFragment=new Room1();
break;
case 3:
myFragment=new Room2();
break;
case 4:
myFragment=new Room3();
break;
case 5:
myFragment=new Kitchen();
break;
case 6:
myFragment=new Other();
break;
case 7:
myFragment=new Help();
break;
case 8:
myFragment=new ContactUs();
break;
}
// update the main content by replacing fragments
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container, myFragment)
.commit();
}
public void onSectionAttached(int number) {
switch (number) {
case 1:
mTitle = getString(R.string.title_section1);
break;
case 2:
mTitle = getString(R.string.title_section2);
break;
case 3:
mTitle = getString(R.string.title_section3);
break;
}
}
public void restoreActionBar() {
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
actionBar.setDisplayShowTitleEnabled(true);
actionBar.setTitle(mTitle);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this screen
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
getMenuInflater().inflate(R.menu.main, menu);
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
if (item.getItemId() == R.id.action_example) {
Intent serverIntent = new Intent(MainActivity.this, DeviceListActivity.class);
startActivityForResult(serverIntent, 1);
return true;
}
return super.onOptionsItemSelected(item);
}
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK) {
String address = data.getExtras()
.getString(DeviceListActivity.EXTRA_DEVICE_ADDRESS);
BluetoothDevice device = myBluetoothadpt.getRemoteDevice(address);
ConnectThread ct = new ConnectThread(device);
ct.start();
}
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
((MainActivity) activity).onSectionAttached(
getArguments().getInt(ARG_SECTION_NUMBER));
}
}
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
// Use a temporary object that is later assigned to mmSocket,
// because mmSocket is final
BluetoothSocket tmp = null;
mmDevice = device;
// Get a BluetoothSocket to connect with the given BluetoothDevice
try {
// MY_UUID is the app's UUID string, also used by the server code
tmp = device.createRfcommSocketToServiceRecord(myUUID);
} catch (IOException e) { }
mmSocket = tmp;
btSocket=mmSocket;
}
public void run() {
// Cancel discovery because it will slow down the connection
myBluetoothadpt.cancelDiscovery();
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mmSocket.connect();
} catch (IOException connectException) {
// Unable to connect; close the socket and get out
try {
mmSocket.close();
} catch (IOException closeException) { }
return;
}
// Do work to manage the connection (in a separate thread)
manageConnectedSocket=new ConnectedThread(btSocket);
}
/** Will cancel an in-progress connection, and close the socket */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the input and output streams, using temp objects because
// member streams are final
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes; // bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while (true) {
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] bytes) {
try {
Log.d("track", "in write" + bytes.toString());
// mmOutStream.flush();
mmOutStream.write(bytes);
// mmOutStream.flush();
} catch (IOException e) { }
}
/* Call this from the main activity to shutdown the connection */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Toast.makeText(MainActivity.this, "you are not connected!!", Toast.LENGTH_SHORT).show();}
}
}
}
这是我的片段：
public class Hall extends Fragment {
ToggleButton t1h;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
t1h.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
String s = "t1o";
Log.d("track", "onCheckedChanged " + isChecked);
MainActivity.sendMessage(s); // this is the method of MAINACTIVITY which then handles sending message over bluetooth
} else {
editor.putBoolean("t1hState", t1h.isChecked());
String s = "t1f";
Log.d("track", "onCheckedChanged " + isChecked);
MainActivity.sendMessage(s);
}
}
});
}
}
答案 0 :(得分：0)
你应该避免在主线程上放置非UI相关的东西。执行此操作时，它会导致主线程挂起（并执行与UI无关的工作）。
因此，您应该将这些作业委派给AsyncTask，以帮助您完成工作并在完成后显示结果。
该工具的一个很好的例子可以在以下位置找到： AsyncTask Android example
答案 1 :(得分：0)
您的UI被挂起，因为您正在当前或主要线程中发送消息。如果你想在后台发送数据而不影响你当前的线程，那么使用AsyncTask并创建分离的线程并将动作放在AsyncTask的PostExcute（）函数中。