用android打印

Question

我想通過藍牙或WiFi從Android 8中的應用程序打印文本文件。請給我解決方案。

Answer 1

這是一個樣本

package com.example.untitled2; 

import android.app.Activity; 
import android.bluetooth.BluetoothAdapter; 
import android.bluetooth.BluetoothDevice; 
import android.bluetooth.BluetoothSocket; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.Button; 
import android.widget.Toast; 

import java.io.IOException; 
import java.io.OutputStream; 
import java.util.Set; 
import java.util.UUID; 

public class MyActivity extends Activity { 
    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); 

    /** 
    * Called when the activity is first created. 
    */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     Button btn = (Button) findViewById(R.id.button); 
     btn.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); 
       if (mBluetoothAdapter == null) { 
        Toast.makeText(MyActivity.this, "no device", Toast.LENGTH_LONG).show(); 
       } 
       if (!mBluetoothAdapter.isEnabled()) { 
        mBluetoothAdapter.enable(); 
       } 
       Set<BluetoothDevice> bluetoothDevices = mBluetoothAdapter.getBondedDevices(); 
       if (bluetoothDevices.size() == 0) 
        return; 
       OutputStream mmOutStream; 
       BluetoothDevice device = bluetoothDevices.iterator().next(); 
       try { 
        BluetoothSocket socket = device.createRfcommSocketToServiceRecord(MY_UUID); 
        socket.connect(); 
        mmOutStream = socket.getOutputStream(); 
        /*String textPrint = ""+(char) 27 + (char)116 + (char) 27;*/ 
        String textPrint = "this is example text"+(char)10; 
        mmOutStream.flush(); 
        mmOutStream.write(textPrint.getBytes()); 
        mmOutStream.flush(); 
        for (int i = 0; i < 10; i++) { 
         mmOutStream.write(textPrint.getBytes()); 
        } 
        mmOutStream.flush(); 
        //mmOutStream.wait(); 
        mmOutStream.close(); 
        socket.close(); 
       } catch (IOException e) { 
        Toast.makeText(MyActivity.this, e.getMessage(), Toast.LENGTH_LONG).show(); 
       } 

      } 
     }); 
    } 
} 

Answer 2

這裏是我的代碼[在線&發現修改按我REQT]連接到藍牙打印機，完美的作品......試了N測試。 :-)

package com.nvsoft.s2pay.mmsl.bluetoothprinter; 

import android.app.Activity; 
import java.io.IOException; 
import java.lang.reflect.InvocationTargetException; 
import java.lang.reflect.Method; 
import java.util.Set; 
import android.bluetooth.BluetoothAdapter; 
import android.bluetooth.BluetoothDevice; 
import android.bluetooth.BluetoothSocket; 
import android.content.BroadcastReceiver; 
import android.content.Context; 
import android.content.Intent; 
import android.content.IntentFilter; 
import android.os.Bundle; 

import com.nvsoft.s2pay.sms.DynaCCSmsServiceConstants; 
import com.nvsoft.s2pay.util.StringUtil; 

import java.util.HashSet; 

import org.json.me.JSONObject; 

import org.slf4j.Logger; 
import org.slf4j.LoggerFactory; 

//This class is meant for wrapping the Bluetooth connecting interface provided by android devices....... 
//Basically is a state machine, and the communications will happen in a separate thread so as not to obstruct the main UI 
public class BTWrapperActivity extends Activity { 
public static final int REQUEST_CONNECT_BT = 0x2300;//8960 
public static final int REQUEST_ENABLE_BT = 0x1000;//4096 
public static final String DEVICES_DISCOVERED = "DD"; 
public static final String EXTRA_DEVICE_ADDRESS = DynaCCSmsServiceConstants.PRINTER_MAC_ADDRESS; 
private static final String ERROR = "ecode"; 
private static final String ERROR_MSG = "emsg"; 
public static int ERROR_CODE = 0; 
int request; 
static private BluetoothAdapter mBluetoothAdapter = null; 
static private Set<BluetoothDevice> btDevices = null; 
String deviceNames = null; 
JSONObject jobj = new JSONObject(); 
Intent parentIntent = null; 
BluetoothDevice selectedDevice = null; 

    static private BluetoothSocket mbtSocket = null; 


@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    Bundle bundle = getIntent().getExtras(); 
    deviceNames = bundle.getString(EXTRA_DEVICE_ADDRESS); 


    parentIntent = getIntent(); 
    request = bundle.getInt(BluetoothFilePrinter.REQUEST_CODE); 

    try { 

      if (request != DynaCCSmsServiceConstants.EXIT_ACTIVITY_REQUEST){ 
       if (initDevicesList() != 0) { 
       this.finish(); 
       return; 
       } 
      } 
    } catch (Exception ex) { 
     getIntent().putExtra(ERROR, 701); 
     getIntent().putExtra(ERROR_MSG, ex.getMessage()); 

     finish(); 
     return; 
    } 
    // Register the Broadcast receiver for handling new BT device discovery 
    //IntentFilter btIntentFilter = new IntentFilter(BluetoothDevice.ACTION_FOUND); 
    //this.registerReceiver(mBTReceiver, new IntentFilter(DynaCCSmsServiceConstants.ACTION_EXIT_ACTIVITY)); 
    this.registerReceiver(mBTReceiver, new IntentFilter(BluetoothDevice.ACTION_FOUND)); 
    this.registerReceiver(mBTReceiver, new IntentFilter(BluetoothDevice.ACTION_ACL_CONNECTED)); 
    this.registerReceiver(mBTReceiver, new IntentFilter(BluetoothDevice.ACTION_ACL_DISCONNECT_REQUESTED)); 
    this.registerReceiver(mBTReceiver, new IntentFilter(BluetoothDevice.ACTION_ACL_DISCONNECTED)); 
    this.registerReceiver(mBTReceiver, new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED)); 
    this.registerReceiver(mBTReceiver, new IntentFilter(Intent.ACTION_SCREEN_ON)); 
    this.registerReceiver(mBTReceiver, new IntentFilter(Intent.ACTION_SCREEN_OFF)); 

    if (request == DynaCCSmsServiceConstants.EXIT_ACTIVITY_REQUEST) { 
     unregisterReceiver(mBTReceiver); 
     this.finish(); 
    } 
} 

public static BluetoothSocket getSocket() { 
    return mbtSocket; 
} 

private void flushData() { 
    try { 
     /*if (mbtSocket != null) { 
     mbtSocket.close(); 
     mbtSocket = null; 
     }*/ 

     if (mBluetoothAdapter != null) { 
      mBluetoothAdapter.cancelDiscovery(); 
     } 

     if (btDevices != null) { 
      btDevices.clear(); 
      btDevices = null; 
     } 
     if (deviceNames!=null) { 
      deviceNames = null; 
     } 
     finalize(); 
     } catch(Exception ex){ 
      getIntent().putExtra(ERROR, 702); 
      getIntent().putExtra(ERROR_MSG, ex.getMessage()); 
    } catch (Throwable e) { 
     getIntent().putExtra(ERROR, 702); 
     getIntent().putExtra(ERROR_MSG, e.getMessage()); 
    } 

} 

// This method will Connect to our SPP Bluetooth Device after discovering and pairing if required 
// Do not forget to add the permission for Bluetooth to use this method 
// Also this method is very tightly coupled with the above method, for getting the status of bt connection 
private int initDevicesList() { 
    // Flush any Pending Data to rediscover devices 
    if (request == DynaCCSmsServiceConstants.DISCOVER_REQUEST) { 
     flushData(); 
    } 
    // Get the Bluetooth Adaptor of the device 
    mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); 
    if (mBluetoothAdapter == null) { 
     return -1; 
    } 
    if (mBluetoothAdapter.isDiscovering()) { 
     mBluetoothAdapter.cancelDiscovery(); 
    } 
    // ENABLE BLUETOOTH on DEVICE if not ALREADY TURNED ON 
    Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE); 
    try { 
     startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT); 
    } catch (Exception ex) { 
     return -2; 
    } 
    return 0; 
} // End getDeviceList 

@Override 
protected void onActivityResult(int reqCode, int resultCode, Intent intent) { 
    super.onActivityResult(reqCode, resultCode, intent); 
    if (intent == null) { 
     intent = getIntent(); 
    } 
    switch (reqCode) { 
     case REQUEST_ENABLE_BT: 
      if (request == DynaCCSmsServiceConstants.DISCOVER_REQUEST) { 
       if (resultCode == RESULT_OK) { 
        // Start getting the paired devices list 
        Set<BluetoothDevice> btDeviceList = mBluetoothAdapter.getBondedDevices(); 
        // If there are paired devices 
        try { 
         if (btDeviceList.size() > 0) { 
          // Loop through paired devices 
          for (BluetoothDevice device : btDeviceList) { 
           jobj.put(device.getName(), device.getAddress()); 
           if (btDeviceList.contains(device) == false) { 
            btDevices.add(device); // Add the device to the device list 
            jobj.put(device.getName(), device.getAddress()); 
           } 
          } 
          if (jobj != null) { 
           intent.putExtra(DEVICES_DISCOVERED, jobj.toString()); 
          } 
          setResult(Activity.RESULT_OK, intent); 
          finish(); 

         } else { 
          mBluetoothAdapter.startDiscovery(); 
         } 
        } catch (Exception ex) { 
         getIntent().putExtra(ERROR, 704); 
         getIntent().putExtra(ERROR_MSG, ex.getMessage()); 
         setResult(Activity.RESULT_CANCELED, intent); 
        } 
       } else { 
        getIntent().putExtra(ERROR, 704); 
        getIntent().putExtra(ERROR_MSG, "Permission to enable Bluetooth on the device was denied. Please enable Bluetooth and retry."); 
        setResult(Activity.RESULT_CANCELED, intent); 
        finish(); 
       } 
      }//end of discovery 
      else if (request == DynaCCSmsServiceConstants.CONNECT_REQUEST || request == DynaCCSmsServiceConstants.PRINT_REQUEST) { 
        if (resultCode == RESULT_OK) { 
         if (deviceNames!=null) { 
          connect(deviceNames); 
         }else{ 
          getIntent().putExtra(ERROR, 704); 
          getIntent().putExtra(ERROR_MSG, "Could not find any printer."); 
          setResult(Activity.RESULT_CANCELED, intent); 
          finish(); 
         } 
        }else{ 
         getIntent().putExtra(ERROR, 704); 
         getIntent().putExtra(ERROR_MSG, "Permission to enable Bluetooth on the device was denied. Please enable Bluetooth and retry."); 
         setResult(Activity.RESULT_CANCELED, intent); 
         finish(); 
        } 
      } 
      break; 
     case REQUEST_CONNECT_BT: 
      if (resultCode == Activity.RESULT_OK) { 
       setResult(Activity.RESULT_OK, intent); 
      } else { 
       setResult(Activity.RESULT_CANCELED, intent); 
      } 
      finish(); 
      break; 
    } 
} 

private final BroadcastReceiver mBTReceiver = new BroadcastReceiver() { 

    @Override 
    public void onReceive(Context context, Intent intent) { 
     String action = intent.getAction(); 
     // Get the BluetoothDevice object from the Intent 
     BluetoothDevice device ; 
     // When discovery finds a device 
     if (BluetoothDevice.ACTION_FOUND.equals(action)) { 
      device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE); 
      try { 
       // No paired device found 
       if (btDevices == null) { 
        btDevices = new HashSet<BluetoothDevice>(); 
        btDevices.add(device); 
        jobj.put(device.getName(), device.getAddress()); 
       } else { 
        if (!btDevices.contains(device)) { 
         btDevices.add(device); 
         jobj.put(device.getName(), device.getAddress()); 
        } 
       } 
       intent.putExtra(DEVICES_DISCOVERED, jobj.toString()); 
      } catch (Exception ex) { 
        getIntent().putExtra(ERROR, 705); 
        getIntent().putExtra(ERROR_MSG, ex.getMessage()); 
      } 
     } else if (BluetoothDevice.ACTION_ACL_CONNECTED.equals(action)) { 
      intent.putExtra("IS_CONNECTED", true); 
     } else if (BluetoothDevice.ACTION_ACL_DISCONNECT_REQUESTED.equals(action)) { 
//#ifndef REMOVE_DEBUG    
       logger.debug("BTWrapperActivity - ", " Device is about to disconnect"); 
//#endif     
      } else if (BluetoothDevice.ACTION_ACL_DISCONNECTED.equals(action)) { 
//#ifndef REMOVE_DEBUG    
       logger.debug("BTWrapperActivity - ", "Device has disconnected"); 
//#endif   
        intent.putExtra("IS_CONNECTED", false); 
      } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) { 
//#ifndef REMOVE_DEBUG    
       logger.debug("BTWrapperActivity - ", "DISCOVERY FINISSHED"); 
//#endif 
       if (request == DynaCCSmsServiceConstants.DISCOVER_REQUEST) { 
        intent.putExtra(DEVICES_DISCOVERED, jobj.toString()); 
        sendDiscoveryResult(intent); 
       } 
      }else if(Intent.ACTION_SCREEN_ON.equals(action)){ 
//#ifndef REMOVE_DEBUG    
       logger.debug("BTWrapperActivity - ", "SCREEN ON"); 
//#endif 
      }else if(Intent.ACTION_SCREEN_OFF.equals(action)){ 
//#ifndef REMOVE_DEBUG    
       logger.debug("BTWrapperActivity - ", "SCREEN OFF"); 
//#endif 
     } 
     } 
    }; 

private void connect(final String deviceAddress) { 
    mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); 
    if (mBluetoothAdapter == null) { 
     return; 
    } else { 
     selectedDevice = mBluetoothAdapter.getRemoteDevice(deviceAddress); 
    } 
    // Cancel the dicovery if still going on 
    if (mBluetoothAdapter.isDiscovering()) { 
     mBluetoothAdapter.cancelDiscovery(); 
    } 
    if (mbtSocket != null) { 
     try { 
      mbtSocket.close(); 
     } catch (IOException ex) { 
      getIntent().putExtra(ERROR, 706); 
      getIntent().putExtra(ERROR_MSG, ex.getMessage()); 
      setResult(Activity.RESULT_CANCELED, getIntent()); 
      finish(); 
     } 
     mbtSocket = null; 
    } 

    // Try to connect with the selected device, 
    // made the thread different as the connecting proceedure might break down the system 
    Thread connectThread = new Thread(new Runnable() { 
     @Override 
     public void run() { 
      Intent intent = getIntent(); 
      String errMsg = ""; 
      try { 
       try { 
        Method m = selectedDevice.getClass().getMethod("createInsecureRfcommSocket", new Class[]{int.class}); 
        try { 
         mbtSocket = (BluetoothSocket) m.invoke(selectedDevice, 1); 
        } catch (IllegalArgumentException e) { 
         errMsg = e.getMessage(); 
         getIntent().putExtra(ERROR, 707); 
         getIntent().putExtra(ERROR_MSG, errMsg); 
        } catch (IllegalAccessException e) { 
         errMsg = e.getMessage(); 
         getIntent().putExtra(ERROR, 708); 
         getIntent().putExtra(ERROR_MSG, errMsg); 
        } catch (InvocationTargetException e) { 
         errMsg = e.getMessage(); 
         getIntent().putExtra(ERROR, 709); 
         getIntent().putExtra(ERROR_MSG, errMsg); 
        }finally{ 
         if (!StringUtil.isEmpty(errMsg) && intent.getExtras().getInt(ERROR)>0) { 
          setResult(Activity.RESULT_CANCELED, getIntent()); 
          finish(); 
         } 
        } 
       } catch (SecurityException e) { 
        errMsg = e.getMessage(); 
        getIntent().putExtra(ERROR, 710); 
        getIntent().putExtra(ERROR_MSG, errMsg); 
        setResult(Activity.RESULT_CANCELED, getIntent()); 
        finish(); 
       } catch (NoSuchMethodException e) { 
        errMsg = e.getMessage(); 
        getIntent().putExtra(ERROR, 711); 
        getIntent().putExtra(ERROR_MSG, errMsg); 
        setResult(Activity.RESULT_CANCELED, getIntent()); 
        finish(); 
       } 
       //mbtSocket = 

selectedDevice.createRfcommSocketToServiceRecord(SPP_UUID); 
        ERROR_CODE = intent.getExtras().getInt(ERROR); 
//#ifndef REMOVE_DEBUG      
        logger.debug("ERROR = ", ERROR_CODE); 
//#endif      
        if (ERROR_CODE == 0) { 
         mbtSocket.connect(); 
//#ifndef REMOVE_DEBUG       
         logger.debug("@@BTWrapperActivity - ", "Connected to selectedDevice = " + (String) intent.getExtras().get(EXTRA_DEVICE_ADDRESS)); 
//#endif 

        intent.putExtra("IS_CONNECTED", true); 
        setResult(Activity.RESULT_OK, intent); 
       } else { 
        intent.putExtra(ERROR, ERROR_CODE); 
        intent.putExtra(ERROR_MSG,errMsg); 
        setResult(Activity.RESULT_CANCELED, intent); 
        finish(); 
       } 
      } catch (IOException ex) { 
       getIntent().putExtra(ERROR, 712); 
       getIntent().putExtra(ERROR_MSG, "Unable to Connect to the Printer. Please verify the printer settings and try again."); 
       getIntent().putExtra("IS_CONNECTED", false); 
       ex.printStackTrace(); 

       setResult(Activity.RESULT_CANCELED, intent); 
       finish(); 
      }finally{ 

       finish(); 
      } 
     } 
    }); 
    connectThread.start(); 

} 

private Runnable socketErrorRunnable = new Runnable() { 
    @Override 
    public void run() { 
     getIntent().putExtra(ERROR, 714); 
     getIntent().putExtra(ERROR_MSG,"Cannot establish connection"); 

     mBluetoothAdapter.startDiscovery(); 
    } 
}; 

protected void onStop() { 

    unregisterReceiver(mBTReceiver); 
    super.onStop(); 
} 

private void sendDiscoveryResult(Intent mIntent){ 
    mIntent.putExtra(DEVICES_DISCOVERED, jobj.toString()); 
    setResult(Activity.RESULT_OK, mIntent); 
    finish(); 
} 

private String getDisplayMessage(){ 
    String message = "Please Wait!!"; 
    switch(request) { 
     case DynaCCSmsServiceConstants.DISCOVER_REQUEST : 
      message = "Discovery in progress!!"; 
      break; 
     case DynaCCSmsServiceConstants.CONNECT_REQUEST: 
      message = "Connecting...Please Wait!!"; 
      break; 
     case DynaCCSmsServiceConstants.PRINT_REQUEST: 
      message = "Printing in progress!!"; 
      break; 
    } 
    return message; 
}} // End of class definition