我试图在eclipse中制作一个基本的蓝牙聊天应用程序，我已经完成了代码并且没有用红色加下划线来提示错误，但当我尝试运行代码时，应用程序意外停止，当我调试代码时它说未找到来源。 我已经为清单添加了蓝牙权限，所以我不这么认为。 任何帮助将不胜感激。 这是代码：
package com.blue;
import android.app.Activity;
import android.os.Bundle;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.UUID;
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.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class BlueActivity extends Activity {
/** Called when the activity is first created. */
public Button btn_Search, btn_Send, btn_Next;
UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
public BluetoothAdapter my_BT_Adapter=BluetoothAdapter.getDefaultAdapter();
public ArrayList<String>BT_Names=new ArrayList<String>();
public ArrayList<String>BT_Addresses=new ArrayList<String>();
public ArrayAdapter<String>aa;
public ArrayAdapter<String>bb;
public TextView txt_Display;
public EditText txt_Message;
public ListView lv_Devices;
public static String address;
public static String right_address;
public BluetoothDevice BT_Device;
public BluetoothSocket BT_Socket;
protected Context context;
Intent intent1 = new Intent();
public int selectedPosition;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btn_Search = (Button)findViewById(R.id.btn_search);
txt_Display = (TextView)findViewById(R.id.txt_display);
lv_Devices = (ListView)findViewById(R.id.lw_Bluetooth_names);
btn_Send = (Button)findViewById(R.id.btn_send);
btn_Next = (Button)findViewById(R.id.btn_next);
txt_Message = (EditText)findViewById(R.id.txt_message);
aa = new ArrayAdapter<String>(this,android.R.layout.simple_gallery_item, BT_Names);
bb = new ArrayAdapter<String>(this,android.R.layout.simple_gallery_item, BT_Addresses);
btn_Send.setFocusable(true);
btn_Next.setEnabled(false);
btn_Search.setOnClickListener(SearchClickHandler);
btn_Next.setOnClickListener(NextClickHandler);
btn_Send.setOnClickListener(SendClickHandler);
BT_Enable();
BroadcastReceiver discoveryResult = new BroadcastReceiver(){
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if(BluetoothDevice.ACTION_FOUND.equals(action)){
String remoteDeviceName=intent.getStringExtra(BluetoothDevice.EXTRA_NAME);
BluetoothDevice remoteDevice;
remoteDevice=intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
BT_Names.add(0, remoteDeviceName);
BT_Addresses.add(0, remoteDevice.getAddress());
aa.notifyDataSetChanged();
bb.notifyDataSetChanged();
}
else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
txt_Display.setText("");
lv_Devices.setAdapter(aa);
if(BT_Names.size()>0){
btn_Search.setClickable(true);
address=BT_Addresses.get(0);
txt_Display.setText(BT_Names.get(0));
btn_Next.setEnabled(true);
lv_Devices.setItemChecked(0, true);
}
else
btn_Search.setClickable(true);
}
}
};
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
this.registerReceiver(discoveryResult, filter);
filter=new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
this.registerReceiver(discoveryResult, filter);
BT_Device=intent1.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
}
public void BT_Enable(){
if(!my_BT_Adapter.isEnabled()){
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, CONTEXT_RESTRICTED);
}
}
View.OnClickListener SearchClickHandler=new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
btn_Search.setClickable(true);
BT_Names.clear();
aa.notifyDataSetChanged();
BT_Addresses.clear();
bb.notifyDataSetChanged();
selectedPosition=0;
txt_Display.setText("Searching...");
btn_Next.setEnabled(true);
if(!my_BT_Adapter.isEnabled()){
try{
my_BT_Adapter.enable();
Toast.makeText(BlueActivity.this, "BT Adapter Enabled", Toast.LENGTH_SHORT).show();
}
catch(Exception e)
{
Toast.makeText(BlueActivity.this, "BT Adapter Unavailable", Toast.LENGTH_SHORT).show();
}
}
if(!my_BT_Adapter.isDiscovering())
my_BT_Adapter.startDiscovery();
}
};
View.OnClickListener NextClickHandler=new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
if(BT_Names.size()>0){
if(selectedPosition<BT_Names.size()){
lv_Devices.setItemChecked(selectedPosition, true);
right_address=BT_Addresses.get(selectedPosition);
selectedPosition++;
}
else
{
selectedPosition=0;
right_address=BT_Addresses.get(selectedPosition);
lv_Devices.setItemChecked(selectedPosition, true);
}
}
txt_Display.setText(BT_Names.get(lv_Devices.getCheckedItemPosition()));
}
};
View.OnClickListener SendClickHandler=new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
if(my_BT_Adapter.isEnabled()&& right_address !="")
{
Thread ConnectThread = new Thread(new Runnable(){
public void run(){
BT_Device=my_BT_Adapter.getRemoteDevice(right_address);
String TAG = null;
Log.e(TAG, BT_Device.getName()+"connected");
try{
BT_Socket=BT_Device.createRfcommSocketToServiceRecord(MY_UUID);
}
catch(IOException e)
{
Log.e(TAG, "ON RESUME: Socket creation failed.", e);
}
Log.e(TAG, "TRYING TO CONNECT");
try{
btn_Send.setClickable(false);
btn_Search.setClickable(false);
btn_Next.setClickable(false);
BT_Socket.connect();
Log .e(TAG, "ON RESUME: BT connection established, data transfer link open.");
}
catch(IOException e)
{
btn_Send.setClickable(true);
btn_Search.setClickable(true);
btn_Next.setClickable(true);
}
try{
Thread.sleep(1000);
OutputStream outStream;
outStream = BT_Socket.getOutputStream();
byte[]byteArray=(txt_Message.getText().toString()).getBytes();
outStream.write(byteArray);
outStream.flush();
Thread.sleep(1500);
BT_Socket.close();
btn_Send.setClickable(true);
btn_Search.setClickable(true);
}
catch(Exception e)
{
txt_Display.setText("Unsuccessful");
}
}
});
ConnectThread.start();
}
else
{
Toast.makeText(BlueActivity.this, "Adapter off or bluetooth not selected", Toast.LENGTH_SHORT).show();
}
}
};
}
先谢谢Chris，
答案 0 :(得分：0)
您的一个findViewById调用可能返回null。我建议你在findViewById之后检查空值。