java.lang.IllegalStateException:无法执行活动的方法,原因是:java.lang.NullPointerException
我发现旅行和人员的详细信息保存在数据库中,然后应用程序崩溃。将数据插入数据库后,它不会返回MainActivity.javajava.lang.IllegalStateException:无法执行活动的方法,原因是:java.lang.NullPointerException,java,android,sqlite,oop,mobile,Java,Android,Sqlite,Oop,Mobile,我发现旅行和人员的详细信息保存在数据库中,然后应用程序崩溃。将数据插入数据库后,它不会返回MainActivity.java 03-29 21:19:50.277: E/Trace(1288): error opening trace file: No such file or directory (2) 03-29 21:20:34.477: E/AndroidRuntime(1288): FATAL EXCEPTION: main 03-29 21:20:34.477: E/
03-29 21:19:50.277: E/Trace(1288): error opening trace file: No such file or directory (2)
03-29 21:20:34.477: E/AndroidRuntime(1288): FATAL EXCEPTION: main
03-29 21:20:34.477: E/AndroidRuntime(1288): java.lang.IllegalStateException: Could not execute method of the activity
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.view.View$1.onClick(View.java:3599)
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.view.View.performClick(View.java:4204)
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.view.View$PerformClick.run(View.java:17355)
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.os.Handler.handleCallback(Handler.java:725)
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.os.Handler.dispatchMessage(Handler.java:92)
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.os.Looper.loop(Looper.java:137)
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.app.ActivityThread.main(ActivityThread.java:5041)
03-29 21:20:34.477: E/AndroidRuntime(1288): at java.lang.reflect.Method.invokeNative(Native Method)
03-29 21:20:34.477: E/AndroidRuntime(1288): at java.lang.reflect.Method.invoke(Method.java:511)
03-29 21:20:34.477: E/AndroidRuntime(1288): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
03-29 21:20:34.477: E/AndroidRuntime(1288): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
03-29 21:20:34.477: E/AndroidRuntime(1288): at dalvik.system.NativeStart.main(Native Method)
03-29 21:20:34.477: E/AndroidRuntime(1288): Caused by: java.lang.reflect.InvocationTargetException
03-29 21:20:34.477: E/AndroidRuntime(1288): at java.lang.reflect.Method.invokeNative(Native Method)
03-29 21:20:34.477: E/AndroidRuntime(1288): at java.lang.reflect.Method.invoke(Method.java:511)
03-29 21:20:34.477: E/AndroidRuntime(1288): at android.view.View$1.onClick(View.java:3594)
03-29 21:20:34.477: E/AndroidRuntime(1288): ... 11 more
03-29 21:20:34.477: E/AndroidRuntime(1288): Caused by: java.lang.NullPointerException
03-29 21:20:34.477: E/AndroidRuntime(1288): at com.example.assignment1.controller.CreateTripActivity.persistTrip(CreateTripActivity.java:104)
03-29 21:20:34.477: E/AndroidRuntime(1288): at com.example.assignment1.controller.CreateTripActivity.createTrip(CreateTripActivity.java:82)
03-29 21:20:34.477: E/AndroidRuntime(1288): ... 14 more
03-29 21:25:36.305: E/Trace(1756): error opening trace file: No such file or directory (2)
CreateTripActivity.java
package com.example.assignment1.controller;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.List;
import java.util.Locale;
import android.app.Activity;
import android.app.DatePickerDialog;
import android.app.TimePickerDialog;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.util.Log;
import android.view.View;
import android.widget.DatePicker;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.TimePicker;
import com.example.assignment1.R;
import com.example.assignment1.model.Person;
import com.example.assignment1.model.Trip;
public class CreateTripActivity extends Activity {
static final String TRIP_KEY="TRIP";
static final String LOG="LOG";
private static final int REQUEST_CONTACT = 2;
Person[] person=new Person[10];
int i=0;
String plist="";
EditText name;
EditText place;
EditText date;
EditText starttime;
EditText endtime;
EditText list;
EditText description;
Calendar c = Calendar.getInstance();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.createtrip);
name=(EditText)findViewById(R.id.nametext);
place=(EditText)findViewById(R.id.placetext);
date=(EditText)findViewById(R.id.datetext);
starttime=(EditText)findViewById(R.id.starttimetext);
endtime=(EditText)findViewById(R.id.endtimetext);
description=(EditText)findViewById(R.id.descriptiontext);
list=(EditText)findViewById(R.id.personlist);
// handling incoming google maps intent
Intent intent = getIntent();
String action = intent.getAction();
String type = intent.getType();
if (Intent.ACTION_SEND.equals(action) && type != null) {
if ("text/plain".equals(type)) {
handleSendText(intent); // Handle text being sent
}
}
}
/**
* This method should be used to
* instantiate a Trip model.
*
* @return The Trip as represented
* by the View.
*/
public Trip createTrip(View v) {
String tripname=name.getText().toString();
String tripplace=place.getText().toString();
String tripdate=date.getText().toString();
String tripstarttime=starttime.getText().toString();
String tripendtime=endtime.getText().toString();
String tripdescription=description.getText().toString();
Trip trip=new Trip(tripname,tripdate,tripstarttime,tripendtime,tripplace,tripdescription,c.getTime().toString());
persistTrip(trip,person);
Log.i("LOG","returning to main");
Intent i=new Intent(this,MainActivity.class);
startActivity(i);
return null;
}
//persist person
public void persistPerson(String name, String phone){
person[i] =new Person(name,phone);
Log.i(LOG,person[i].getName());
i +=1;
}
/*
persist trip to database
*/
public void persistTrip(Trip trip,Person[] person) {
DBAdapter db=new DBAdapter(this);
db.open();
db.insertTrip(trip.getName(),trip.getPlace(), trip.getDate(), trip.getStartTime(),trip.getEndTime(),trip.getDescription(),trip.getCreatetime());
for(i=0;i<person.length;i++)
{
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
db.insertPerson(person[i].getName(),person[i].getPhone());
}
db.close();
}
/**
* This method should be used when a
* user wants to cancel the creation of
* a Trip.
*
* Note: You most likely want to call this
* if your activity dies during the process
* of a trip creation or if a cancel/back
* button event occurs. Should return to
* the previous activity without a result
* using finish() and setResult().
*/
public void cancelTripCreation(View v) {
Intent back=new Intent(this,MainActivity.class);
setResult(RESULT_OK,back);
finish();
}
//Datepickerlistener
DatePickerDialog.OnDateSetListener datepick = new DatePickerDialog.OnDateSetListener() {
@Override
public void onDateSet( DatePicker view, int year, int monthOfYear, int dayOfMonth ) {
c.set( Calendar.YEAR, year );
c.set( Calendar.MONTH, monthOfYear );
c.set( Calendar.DAY_OF_MONTH, dayOfMonth );
setCurrentDateOnView();
}
};
//Date picker
public void dateOnClick( View view ) {
Log.i(LOG,"Date clicked");
new DatePickerDialog(CreateTripActivity.this, datepick,
c.get( Calendar.YEAR ), c.get( Calendar.MONTH ), c.get( Calendar.DAY_OF_MONTH ) ).show();
}
//listener for timepickerdialog
TimePickerDialog.OnTimeSetListener timepick = new TimePickerDialog.OnTimeSetListener() {
@Override
public void onTimeSet( TimePicker view, int hourOfDay, int minute ) {
c.set( Calendar.HOUR_OF_DAY, hourOfDay );
c.set( Calendar.MINUTE, minute );
setCurrentDateOnView();
}
};
//time picker
public void timeOnClick( View view ) {
new TimePickerDialog( CreateTripActivity.this, timepick,
c.get( Calendar.HOUR ), c.get( Calendar.MINUTE ), false ).show();
}
public void setCurrentDateOnView() {
String dateFormat = "MM/dd/yyyy";
SimpleDateFormat sdf = new SimpleDateFormat( dateFormat, Locale.US );
date.setText( sdf.format( c.getTime() ) );
String timeFormat = "hh:mm a";
SimpleDateFormat stf = new SimpleDateFormat( timeFormat, Locale.US );
starttime.setText( stf.format( c.getTime() ) );
}
//listener for timepickerdialog
TimePickerDialog.OnTimeSetListener endtimepick = new TimePickerDialog.OnTimeSetListener() {
@Override
public void onTimeSet( TimePicker view, int hourOfDay, int minute ) {
c.set( Calendar.HOUR_OF_DAY, hourOfDay );
c.set( Calendar.MINUTE, minute );
setCurrentDateOnView1();
}
};
//time picker
public void endtimeOnClick( View view ) {
new TimePickerDialog( CreateTripActivity.this, endtimepick,
c.get( Calendar.HOUR ), c.get( Calendar.MINUTE ), false ).show();
}
public void setCurrentDateOnView1() {
String dateFormat = "MM/dd/yyyy";
SimpleDateFormat sdf = new SimpleDateFormat( dateFormat, Locale.US );
date.setText( sdf.format( c.getTime() ) );
String timeFormat = "hh:mm a";
SimpleDateFormat stf = new SimpleDateFormat( timeFormat, Locale.US );
endtime.setText( stf.format( c.getTime() ) );
}
// add persons to trip via phonebook
public void contacts(View v) {
Intent i = new Intent(Intent.ACTION_PICK,
ContactsContract.Contacts.CONTENT_URI);
startActivityForResult(i, REQUEST_CONTACT);
Log.i(LOG,"went");
}
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_CONTACT) {
Uri uri = data.getData();
String[] projection = new String[] {ContactsContract.Contacts.DISPLAY_NAME
// ContactsContract.CommonDataKinds.Phone.NUMBER
};
Cursor people = getContentResolver().query(uri, projection, null, null, null);
int indexName = people.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME);
//int indexNumber = people.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER);
people.moveToFirst();
do {
String name = people.getString(indexName);
String number = null;
persistPerson(name,number);
plist +=name+"\n";
// plist +=number;
} while (people.moveToNext());
}
list.setText(plist);
}
public void googleMaps(View v){
// Build the intent
Uri location = Uri.parse("geo:0,0?q=1600+Amphitheatre+Parkway,+Mountain+View,+California");
Intent mapIntent = new Intent(Intent.ACTION_VIEW, location);
// Verify it resolves
PackageManager packageManager = getPackageManager();
List<ResolveInfo> activities = packageManager.
queryIntentActivities(mapIntent, 0);
boolean isIntentSafe = activities.size() > 0;
// Start an activity if it's safe
if (isIntentSafe) {startActivity(mapIntent);}
}
//handling incoming intent from google map
void handleSendText(Intent intent) {
String sharedText = intent.getStringExtra(Intent.EXTRA_TEXT);
if (sharedText != null) {
// Update UI to reflect text being shared
place.setText(sharedText);
}
}
}
您已使用初始化person数组
Person[] person = new Person[10];
但是,在persistTrip方法中,您迭代该数组,并且第一个元素(person[0])为null,因此行上的NPE为空
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
这是因为对象的默认值为null
要正确初始化Person对象数组,应使用:
for (int i = 0; i < 10; i++) {
person[i] = new Person();
}
for(int i=0;i<10;i++){
person[i]=新的person();
}
或者使用空检查包装数组的使用。您已使用
Person[] person = new Person[10];
但是,在persistTrip方法中,您迭代该数组,并且第一个元素(person[0])为null,因此行上的NPE为空
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
这是因为对象的默认值为null
要正确初始化Person对象数组,应使用:
for (int i = 0; i < 10; i++) {
person[i] = new Person();
}
for(int i=0;i<10;i++){
person[i]=新的person();
}
或者使用空检查包装数组的使用。您已使用
Person[] person = new Person[10];
但是,在persistTrip方法中,您迭代该数组,并且第一个元素(person[0])为null,因此行上的NPE为空
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
这是因为对象的默认值为null
要正确初始化Person对象数组,应使用:
for (int i = 0; i < 10; i++) {
person[i] = new Person();
}
for(int i=0;i<10;i++){
person[i]=新的person();
}
或者使用空检查包装数组的使用。您已使用
Person[] person = new Person[10];
但是,在persistTrip方法中,您迭代该数组,并且第一个元素(person[0])为null,因此行上的NPE为空
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
这是因为对象的默认值为null
要正确初始化Person对象数组,应使用:
for (int i = 0; i < 10; i++) {
person[i] = new Person();
}
for(int i=0;i<10;i++){
person[i]=新的person();
}
或者使用空检查包装数组的使用。当您在第104行获得NPE时,即:
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
3.可能性是存在的
1-一个或多个名称为空,因此person[i].getName()
throw NPE
2-一个或多个电话为空,因此person[i].getPhone()
throw NPE
3-一个或多个人员未初始化
如何才能找到?
在for语句中使用log和printi
,并查找哪个位置为空
更好的方法
使用Arraylist
编写代码
ArrayList<Person> persons = new ArrayList<Person>()
arraylistpersons=new ArrayList()
当您在第104行获得NPE时,即:
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
3.可能性是存在的
1-一个或多个名称为空,因此person[i].getName()
throw NPE
2-一个或多个电话为空,因此person[i].getPhone()
throw NPE
3-一个或多个人员未初始化
如何才能找到?
在for语句中使用log和printi
,并查找哪个位置为空
更好的方法
使用Arraylist
编写代码
ArrayList<Person> persons = new ArrayList<Person>()
arraylistpersons=new ArrayList()
当您在第104行获得NPE时,即:
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
3.可能性是存在的
1-一个或多个名称为空,因此person[i].getName()
throw NPE
2-一个或多个电话为空,因此person[i].getPhone()
throw NPE
3-一个或多个人员未初始化
如何才能找到?
在for语句中使用log和printi
,并查找哪个位置为空
更好的方法
使用Arraylist
编写代码
ArrayList<Person> persons = new ArrayList<Person>()
arraylistpersons=new ArrayList()
当您在第104行获得NPE时,即:
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
3.可能性是存在的
1-一个或多个名称为空,因此person[i].getName()
throw NPE
2-一个或多个电话为空,因此person[i].getPhone()
throw NPE
3-一个或多个人员未初始化
如何才能找到?
在for语句中使用log和printi
,并查找哪个位置为空
更好的方法
使用Arraylist
编写代码
ArrayList<Person> persons = new ArrayList<Person>()
arraylistpersons=new ArrayList()
ya,您正在迭代person数组,并假设其中包含10个已初始化的对象-这不是因为您获得了NPE
要快速修复此问题,请将persistTrip方法更改为
public void persistTrip(Trip trip,Person[] person) {
DBAdapter db=new DBAdapter(this);
db.open();
db.insertTrip(trip.getName(),trip.getPlace(), trip.getDate(), trip.getStartTime(),trip.getEndTime(),trip.getDescription(),trip.getCreatetime());
for(i=0;i<person.length;i++)
{
if (person[i] != null) {
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
db.insertPerson(person[i].getName(),person[i].getPhone());
}
}
db.close();
}
公共出行(出行,人[]人){
DBAdapter db=新的DBAdapter(此);
db.open();
db.insertTrip(trip.getName()、trip.getPlace()、trip.getDate()、trip.getStartTime()、trip.getEndTime()、trip.getDescription()、trip.getCreatetime());
对于(i=0;iya),您正在对person数组进行迭代,并假设它包含10个初始化的对象-这不是因为您得到了NPE
要快速修复此问题,请将persistTrip方法更改为
public void persistTrip(Trip trip,Person[] person) {
DBAdapter db=new DBAdapter(this);
db.open();
db.insertTrip(trip.getName(),trip.getPlace(), trip.getDate(), trip.getStartTime(),trip.getEndTime(),trip.getDescription(),trip.getCreatetime());
for(i=0;i<person.length;i++)
{
if (person[i] != null) {
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
db.insertPerson(person[i].getName(),person[i].getPhone());
}
}
db.close();
}
公共出行(出行,人[]人){
DBAdapter db=新的DBAdapter(此);
db.open();
db.insertTrip(trip.getName()、trip.getPlace()、trip.getDate()、trip.getStartTime()、trip.getEndTime()、trip.getDescription()、trip.getCreatetime());
对于(i=0;iya),您正在对person数组进行迭代,并假设它包含10个初始化的对象-这不是因为您得到了NPE
要快速修复此问题,请将persistTrip方法更改为
public void persistTrip(Trip trip,Person[] person) {
DBAdapter db=new DBAdapter(this);
db.open();
db.insertTrip(trip.getName(),trip.getPlace(), trip.getDate(), trip.getStartTime(),trip.getEndTime(),trip.getDescription(),trip.getCreatetime());
for(i=0;i<person.length;i++)
{
if (person[i] != null) {
Log.i(LOG,"inserting person"+person[i].getName()+person[i].getPhone());
db.insertPerson(person[i].getName(),person[i].getPhone());
}
}
db.close();
}
公共出行(出行,人[]人){
DBAdapter db=新的DBAdapter(此);
db.open();
db.insertTrip(trip.getName()、trip.getPlace()、trip.getDate()、trip.getStartTime()、trip.getEndTime()、trip.getDescription()、trip.getCreatetime());
对于(i=0;iya),您正在迭代person数组并