我已经在Android 2.3.6（API 10）上开发了我的应用程序工作正常然后我从Activity退出但是它的服务在1小时后在后台执行，当我再次运行它然后它由于一些致命异常它强制停止，但再次运行并正常工作。
请帮助我理解这个堆栈跟踪并帮我解决这个问题。
提前谢谢。
OnOffScreen类：
public class OnOffScreen extends Activity {
private TextView txtDevId,txtdevTag,txtOnOffSt,btnonoffMain,lblAlarm,txtMonitor,txtVersion,txtOcc;
private TextView txtOnOffDevType,txtTimerApp,txtStartTime,txtStartAct,txtStopTime,txtStopAct;
private ListView lstDeviceInfo;
private Button btnReport,btnOn,btnOff,btnConfig,btnStatus;
@SuppressWarnings("unused")
private Context context;
private ExceptionDialog dlg;
private SharedPreferences prefs;
private DataBaseAdapter dba;
private UtilityFunction utility;
@SuppressWarnings("unused")
private ImageView imgMain;
private String DevId,SwId;
private Bundle bundle;
private SendSMS smsSend;
private SMSReceiver receivedSms;
private Cursor cursor,curCord;
private customCursorAdapter adpt;
private TableRow trSwitchId;
@SuppressWarnings("unused")
private ConstantClass ccl;
private static String SMS_RECEIVED = "android.provider.Telephony.SMS_RECEIVED";
public OnOffScreen(){
dba = new DataBaseAdapter(this);
smsSend = new SendSMS(this);
receivedSms = new SMSReceiver(this);
utility = new UtilityFunction(this);
ccl = new ConstantClass();
}
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
final boolean isCsTitle = requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
setContentView(R.layout.onoffscr);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
if(isCsTitle)
getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.title);
final TextView mtxTitle = (TextView)findViewById(R.id.lblMyTitle);
mtxTitle.setText("Device On/Off Screen");
ConstantClass.Clear_Main_Screen=false;
ConstantClass.afterSendGotoMain = true;
try{
if(dba.IsConOpenOrClose()==false)
dba.Open();
bundle = getIntent().getExtras();
if(bundle!=null){
DevId = bundle.getString("devIdTag");
SwId = bundle.getString("SwIdTag");
prefs = getPreferences(MODE_PRIVATE);
SharedPreferences.Editor editor = prefs.edit();
editor.putString("DeviceId", DevId);
editor.putString("SwitchId", SwId);
//////finally saved the data/////////
editor.commit();
}
txtDevId = (TextView)findViewById(R.id.txtOnScDevID);
txtdevTag = (TextView)findViewById(R.id.txtOnScDevTag);
txtOnOffSt = (TextView)findViewById(R.id.txtOnScDevStatus);
txtMonitor = (TextView) findViewById(R.id.txtOnScDevMonitor);
txtOnOffDevType = (TextView)findViewById(R.id.txtonoffDevType);
txtVersion = (TextView)findViewById(R.id.txtOnOffDevAppVer);
lstDeviceInfo = (ListView)findViewById(R.id.lstDeviceInfo);
lblAlarm = (TextView)findViewById(R.id.lblOnOffAlarm);
txtTimerApp = (TextView)findViewById(R.id.txtOnOffDevTimer);
txtOcc = (TextView)findViewById(R.id.txtOnOffDevOcc);
txtStartTime = (TextView)findViewById(R.id.txtOnOffStartTime);
txtStartAct = (TextView)findViewById(R.id.txtOnOffDevStartAct);
txtStopTime = (TextView)findViewById(R.id.txtOnOffDevStopTime);
txtStopAct = (TextView)findViewById(R.id.txtOnOffDevStopAct);
//imgMain = (ImageView)findViewById(R.id.imgOnOffDevice);
btnOn = (Button)findViewById(R.id.btnOnOffOn);
btnOff = (Button)findViewById(R.id.btnOnOffOff);
btnStatus = (Button)findViewById(R.id.btnStatus);
btnConfig = (Button)findViewById(R.id.btnOnOffConfig);
btnReport = (Button)findViewById(R.id.btnOnOffSeeReport);
btnonoffMain = (Button)findViewById(R.id.btnOnOffMain);
trSwitchId = (TableRow)findViewById(R.id.tbRowSwitchId);
btnOn.setOnClickListener(btnClick);
btnOn.setBackgroundResource(R.drawable.onbutton);
btnOff.setOnClickListener(btnClick);
btnOff.setBackgroundResource(R.drawable.offbutton);
btnStatus.setOnClickListener(btnClick);
btnStatus.setBackgroundResource(R.drawable.checkstatus);
btnConfig.setOnClickListener(btnClick);
btnonoffMain.setOnClickListener(btnClick);
btnReport.setOnClickListener(btnClick);
if(SwId.equals("0000")){
trSwitchId.setVisibility(TableRow.GONE);
}else
trSwitchId.setVisibility(TableRow.VISIBLE);
/************Filling the Coordinator number to cursor***************/
curCord = dba.getCoord(dba.CurrentWorkingCoordinator(DataBaseAdapter.Key_SendCoord, 1));
if(curCord!=null){
ConstantClass.address = curCord.getString(curCord.getColumnIndex(DataBaseAdapter.Key_MbNo)).toString();
startManagingCursor(curCord);
}
cursor = dba.SelFromDeviceStorage(DevId, SwId);
startManagingCursor(cursor);
if (cursor.getCount()>0){
fillControl(cursor);
}
String tag = cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevTag));
String alarm =utility.ReturnAlarm(DevId, tag);
lblAlarm.setText(alarm);
lblAlarm.setFocusable(true);
lblAlarm.setOnClickListener(btnClick);
}catch(SQLiteException e){
Toast.makeText(this,e.getMessage(), Toast.LENGTH_SHORT).show();
}finally{
if(curCord!=null)
curCord.close();
}
}
View.OnClickListener btnClick = new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
switch(v.getId()){
case R.id.lblOnOffAlarm:
if(lblAlarm.getText().toString()!=null){
dlg = new ExceptionDialog(OnOffScreen.this,"Alarm " ,lblAlarm.getText().toString());
dlg.show();
}
break;
case R.id.btnOnOffOn:
try{
//ConstantClass.address = "5556";
if (ConstantClass.timer != null)
ConstantClass.timer.cancel();
ConstantClass.timer = new Timer();
ConstantClass.timer.schedule(new AuditTimerTask(OnOffScreen.this), 300000);
String msg = "<"+Integer.toHexString(26)+"3" + txtDevId.getText().toString() + SwId + Integer.toHexString(1)+">";
smsSend.send_SMS( msg.toUpperCase());
////////go to mainn Screen //////
}catch(Exception e){
Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
}
break;
case R.id.btnOnOffOff:
try{
//ConstantClass.address = "5556";
if (ConstantClass.timer != null)
ConstantClass.timer.cancel();
ConstantClass.timer = new Timer();
ConstantClass.timer.schedule(new AuditTimerTask(OnOffScreen.this),300000);
String msg = "<"+Integer.toHexString(26)+"3" + txtDevId.getText().toString() + SwId + Integer.toHexString(0)+">";
smsSend.send_SMS( msg.toUpperCase());
//////////now going to Main Screen//////////////
}catch(Exception e){
Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
}
break;
case R.id.btnStatus:
try{
if (ConstantClass.timer != null)
ConstantClass.timer.cancel();
ConstantClass.timer = new Timer();
ConstantClass.timer.schedule(new AuditTimerTask(OnOffScreen.this),300000);
String msg = "<"+Integer.toHexString(26)+"3" + txtDevId.getText().toString() + SwId + Integer.toHexString(9)+">";
smsSend.send_SMS( msg.toUpperCase());
}catch(Exception e){
Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
}
break;
case R.id.btnOnOffConfig:
/*
* code for go on to the Config Device Screen from OnOffScreen *
*/
Intent onOffConfig = new Intent(OnOffScreen.this,ConfigDevice.class);
onOffConfig.putExtra("DeviceId", txtDevId.getText().toString());
onOffConfig.putExtra("SwId", SwId);
OnOffScreen.this.startActivity(onOffConfig);
break;
case R.id.btnOnOffMain:
/*
* code for go on to main Zigbee Activity Class from the OnOffScreen *
*/
try{
Intent onOffMain = new Intent(OnOffScreen.this,ZigbeeActivity.class);
onOffMain.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
if(dba.IsConOpenOrClose()==false)
dba.Open();
String sQuery = new String("UPDATE " + ConstantClass.dbName[3] + " SET " + DataBaseAdapter.Key_AlarmID + " = " + "0" +
" WHERE " + DataBaseAdapter.Key_AlarmDevID + " = ?");
dba.UpdateQuery(sQuery, DevId);
OnOffScreen.this.startActivity(onOffMain);
}catch(Exception e){
Toast.makeText(OnOffScreen.this, "On OffScreen " + e.getMessage(),Toast.LENGTH_LONG).show();
}
break;
case R.id.btnOnOffSeeReport:
Intent rptInt = new Intent(OnOffScreen.this,ReportHistory.class);
String dTag = null,stag = null,devsr=null, pic=null;
if(cursor!=null){
DevId = cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevID));
SwId = cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_SwID));
dTag = cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevTag));
stag = cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_SwTag));
devsr = String.valueOf(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevSr)));
pic = String.valueOf(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevPic)));
rptInt.putExtra("DeviceID",DevId);
rptInt.putExtra("SwitchId", SwId);
rptInt.putExtra("DeviceTag", dTag);
rptInt.putExtra("SwitchTag",stag );
rptInt.putExtra("DeviceSr", devsr);
rptInt.putExtra("DevicePic", pic);
OnOffScreen.this.startActivity(rptInt);
}
else
OnOffScreen.this.startActivity(rptInt);
break;
}
}
};
@Override
public void onStart(){
super.onStart();
///////registering the Receiver for sms receiving///////////
registerReceiver(smsSend.sms_send,smsSend.getSentIntentFilter());
registerReceiver(smsSend.sms_delivered,smsSend.getDeliveredFilter());
IntentFilter filter = new IntentFilter(SMS_RECEIVED);
registerReceiver(receivedSms,filter);
}
@Override
public void onResume(){
super.onResume();
try{
dba.Open();
//////loading the prefrences////////
SharedPreferences prefs = getPreferences(MODE_PRIVATE);
DevId = prefs.getString("DeviceId", "");
SwId = prefs.getString("SwitchId", "");
cursor = dba.SelFromDeviceStorage(DevId, SwId);
startManagingCursor(cursor);
if (cursor.getCount()>0){
fillControl(cursor);
}
}catch(Exception e){
Log.d("Resume On Off", e.getMessage());
}
}
@Override
public void onPause(){
super.onPause();
if(cursor!=null)
cursor.close();
ConstantClass.Clear_Main_Screen = true;
}
@Override
public void onBackPressed(){
try{
Intent onOffMain = new Intent(OnOffScreen.this,ZigbeeActivity.class);
onOffMain.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
if(dba.IsConOpenOrClose()==false)
dba.Open();
String sQuery = new String("UPDATE " + ConstantClass.dbName[3] + " SET " + DataBaseAdapter.Key_AlarmID + " = " + "0" +
" WHERE " + DataBaseAdapter.Key_AlarmDevID + " = ?");
dba.UpdateQuery(sQuery, DevId);
OnOffScreen.this.startActivity(onOffMain);
}catch(Exception e){
Toast.makeText(OnOffScreen.this, "On OffScreen " + e.getMessage(),Toast.LENGTH_LONG).show();
}
}
@Override
public void onDestroy(){
super.onDestroy();
unregisterReceiver(receivedSms);
unregisterReceiver(smsSend.sms_send);
unregisterReceiver(smsSend.sms_delivered);
if(cursor!=null)
cursor.close();
if(dba!=null)
dba.Close();
}
public String setDtTime(String temp){
String dd,mm,yy,hh,min;
dd = temp.substring(0, 2);
mm = temp.substring(2, 4);
int mon = Integer.valueOf(mm);
mm = Integer.toString(mon+1);
if(mm.length()!=2)
mm = "0" + mm;
yy = temp.substring(4, 6);
hh = temp.substring(6, 8);
min = temp.substring(8, 10);
return dd+"/" + mm + "/" + yy + " " + hh + ":" + min;
}
public void fillControl(Cursor cursor){
try{
if(cursor!=null)
cursor.moveToFirst();
adpt = new customCursorAdapter(this,cursor);
lstDeviceInfo.setAdapter(adpt);
txtDevId.setText(cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevID)).toString());
txtDevId.setTextColor(Color.BLACK);
txtdevTag.setText(cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevTag)));
txtdevTag.setTextColor(Color.BLACK);
if(cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_SwID)).toString().equals("0000")){
txtOnOffDevType.setText("Plug");
}else
txtOnOffDevType.setText("Switch");
txtOnOffDevType.setTextColor(Color.BLACK);
if(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevOnOff))==1)
txtOnOffSt.setText("ON");
else
txtOnOffSt.setText("OFF");
txtMonitor.setTextColor(Color.BLACK);
if(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevRu))==1)
txtMonitor.setText("Yes");
else
txtMonitor.setText("NO");
txtOnOffSt.setTextColor(Color.BLACK);
if(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevTmr))==2)
txtTimerApp.setText("Yes");
else
txtTimerApp.setText("NO");
txtTimerApp.setTextColor(Color.BLACK);
if((cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevOc))==1)|| cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevOc))==0){
txtOcc.setText("Once");
}else if(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevOc))==2){
txtOcc.setText("Daily");
}else if(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevOc))==4){
txtOcc.setText("Annualy");
}else
txtOcc.setText("Weakly");
txtOcc.setTextColor(Color.BLACK);
String onTime = cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevOnTm)).toString();
/* for catching the On Status Device */
txtStartTime.setText(setDtTime( onTime));
txtStartTime.setTextColor(Color.BLACK);
if(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevOnSt))==1)
txtStartAct.setText("ON");
else
txtStartAct.setText("OFF");
txtStartAct.setTextColor(Color.BLACK);
String offTime =cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevOffTm)).toString();
/* for getting the timer Off act from the dbase*/
txtStopTime.setText(setDtTime(offTime));
txtStopTime.setTextColor(Color.BLACK);
if(cursor.getInt(cursor.getColumnIndex(DataBaseAdapter.Key_DevOffSt))==1)
txtStopAct.setText("ON");
else
txtStopAct.setText("OFF");
txtStopAct.setTextColor(Color.BLACK);
String tem = cursor.getString(cursor.getColumnIndex(DataBaseAdapter.Key_DevVersion));
txtVersion.setText(tem.substring(0, 1)+ "." + tem.substring(1, 2) + "." + tem.substring(2));
txtVersion.setTextColor(Color.BLACK);
}catch(Exception e){
Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_LONG).show();
}
}
}
堆栈跟踪：
06-15 14:37:35.734: E/AndroidRuntime(31310): FATAL EXCEPTION: main
06-15 14:37:35.734: E/AndroidRuntime(31310): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.zigbee/com.zigbee.OnOffScreen}: java.lang.NullPointerException
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.os.Handler.dispatchMessage(Handler.java:99)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.os.Looper.loop(Looper.java:130)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.app.ActivityThread.main(ActivityThread.java:3687)
06-15 14:37:35.734: E/AndroidRuntime(31310): at java.lang.reflect.Method.invokeNative(Native Method)
06-15 14:37:35.734: E/AndroidRuntime(31310): at java.lang.reflect.Method.invoke(Method.java:507)
06-15 14:37:35.734: E/AndroidRuntime(31310): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
06-15 14:37:35.734: E/AndroidRuntime(31310): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
06-15 14:37:35.734: E/AndroidRuntime(31310): at dalvik.system.NativeStart.main(Native Method)
06-15 14:37:35.734: E/AndroidRuntime(31310): Caused by: java.lang.NullPointerException
06-15 14:37:35.734: E/AndroidRuntime(31310): at com.zigbee.OnOffScreen.onCreate(OnOffScreen.java:122)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
06-15 14:37:35.734: E/AndroidRuntime(31310): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
06-15 14:37:35.734: E/AndroidRuntime(31310): ... 11 more
答案 0 :(得分：1)
您在此声明中遇到问题
if (SwId.equals("0000")) {
您正在onCreate中调用此语句，并且您正在onResume中初始化它。
SwId = prefs.getString("SwitchId", "");
这就是你得到Exception的原因。总是记得当你启动应用程序时它首先调用onCreate，然后再调用onResume。
您只能在以下条件下在onCreate中启动它
if (bundle != null) {
DevId = bundle.getString("devIdTag");
SwId = bundle.getString("SwIdTag");
}
因此，当您的应用程序启动时，第一个bundle将为null，并且此条件将不会执行，您的应用程序将崩溃。
答案 1 :(得分：0)
你有NullPointerException，因为null对象尝试调试你的应用程序