Java CursorIndexOutOfBoundsException错误-数据库android
我知道这个问题反复出现,但没有一个解决方案对我有效 我是sql数据库新手。我正在练习来自网站教程点的示例。例子 我正在获取.CursorIndexOutOfBoundsException:请求索引0,从数据库中删除名称时出现大小为0的错误。因此,如果我在数据库中添加4个名称并开始删除第一个名称,它将被删除,然后单击第二个名称,它将显示此错误(.CursorIndexOutOfBoundsException:请求索引0,大小为0)。然后,如果我点击第三个名字,我可以删除这个名字,但第四个名字也会出现同样的错误。 我希望用户可以从数据库中删除任何行,或者可以删除整行 错误 分贝Java CursorIndexOutOfBoundsException错误-数据库android,java,android,database,sqlite,Java,Android,Database,Sqlite,我知道这个问题反复出现,但没有一个解决方案对我有效 我是sql数据库新手。我正在练习来自网站教程点的示例。例子 我正在获取.CursorIndexOutOfBoundsException:请求索引0,从数据库中删除名称时出现大小为0的错误。因此,如果我在数据库中添加4个名称并开始删除第一个名称,它将被删除,然后单击第二个名称,它将显示此错误(.CursorIndexOutOfBoundsException:请求索引0,大小为0)。然后,如果我点击第三个名字,我可以删除这个名字,但第四个名字也会出
public类DBHelper扩展了SQLiteOpenHelper{
公共静态最终字符串数据库\u NAME=“MyDBName.db”;
公共静态最终字符串CONTACTS\u TABLE\u NAME=“CONTACTS”;
公共静态最终字符串联系人\u COLUMN\u ID=“ID”;
公共静态最终字符串CONTACTS\u COLUMN\u NAME=“NAME”;
私有HashMap-hp;
公共DBHelper(上下文){
super(上下文,数据库名称,null,1);
}
@凌驾
public void onCreate(SQLiteDatabase db){
db.execSQL(
“创建表联系人”+
(id整数主键,名称文本)
);
}
@凌驾
public void onUpgrade(SQLiteDatabase db,int-oldVersion,int-newVersion){
db.execSQL(“如果存在联系人,则删除表”);
onCreate(db);
}
公共布尔值insertContact(字符串名称){
SQLiteDatabase db=this.getWritableDatabase();
ContentValues ContentValues=新ContentValues();
contentValues.put(“name”,name);
db.insert(“contacts”,null,contentValues);
返回true;
}
公共游标getData(int-id){
SQLiteDatabase db=this.getReadableDatabase();
Cursor res=db.rawQuery(“从联系人中选择*,其中id=“+id+”,null);
返回res;
}
公共int numberOfRows(){
SQLiteDatabase db=this.getReadableDatabase();
int numRows=(int)DatabaseUtils.queryNumEntries(db,CONTACTS\u TABLE\u NAME);
返回numRows;
}
公共布尔updateContact(整数id、字符串名称){
SQLiteDatabase db=this.getWritableDatabase();
ContentValues ContentValues=新ContentValues();
contentValues.put(“name”,name);
update(“contacts”,contentValues,“id=?”,新字符串[]{Integer.toString(id)});
返回true;
}
公共整数删除联系人(整数id){
SQLiteDatabase db=this.getWritableDatabase();
返回db.delete(“联系人”,
“id=?”,
新字符串[]{Integer.toString(id)});
}
公共阵列列表getAllCotacts(){
ArrayList数组_list=新建ArrayList();
//hp=新HashMap();
SQLiteDatabase db=this.getReadableDatabase();
Cursor res=db.rawQuery(“从联系人中选择*”,null);
res.moveToFirst();
while(res.isAfterLast()==false){
array_list.add(res.getString(res.getColumnIndex(CONTACTS_COLUMN_NAME));
res.moveToNext();
}
返回数组_列表;
}
设备详细性
public class devicedetailsActivity extends AppCompatActivity {
public final static String EXTRA_MESSAGE = "MESSAGE";
private ListView obj;
DBHelper mydb;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.devicedetails_layout);
FullScreencall();
mydb = new DBHelper(this);
ArrayList array_list = mydb.getAllCotacts();
ArrayAdapter arrayAdapter=new ArrayAdapter(this,R.layout.simple_list_item_1, array_list);
obj = (ListView)findViewById(R.id.listView1);
obj.setAdapter(arrayAdapter);
obj.setOnItemClickListener(new AdapterView.OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,long arg3) {
// TODO Auto-generated method stub
int id_To_Search = arg2 + 1;
Bundle dataBundle = new Bundle();
dataBundle.putInt("id", id_To_Search);
Intent intent = new Intent(getApplicationContext(),DetailsActivity.class);
intent.putExtras(dataBundle);
startActivity(intent);
}
});
}
public void FullScreencall() {
if(Build.VERSION.SDK_INT > 11 && Build.VERSION.SDK_INT < 19) { // lower api
int mUIFlag = View.SYSTEM_UI_FLAG_LOW_PROFILE
| View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_FULLSCREEN;
getWindow().getDecorView().setSystemUiVisibility(mUIFlag);
} else if(Build.VERSION.SDK_INT >= 19) {
//for new api versions.
View decorView = getWindow().getDecorView();
int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
| View.SYSTEM_UI_FLAG_FULLSCREEN;
decorView.setSystemUiVisibility(uiOptions);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
getMenuInflater().inflate(R.menu.home, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item){
super.onOptionsItemSelected(item);
switch(item.getItemId()) {
case R.id.item1:Bundle dataBundle = new Bundle();
dataBundle.putInt("id", 0);
Intent intent = new Intent(getApplicationContext(),DetailsActivity.class);
intent.putExtras(dataBundle);
startActivity(intent);
return true;
case R.id.item2: dataBundle = new Bundle();
dataBundle.putInt("id", 0);
intent = new Intent(getApplicationContext(),MainActivity.class);
intent.putExtras(dataBundle);
startActivity(intent);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public boolean onKeyDown(int keycode, KeyEvent event) {
if (keycode == KeyEvent.KEYCODE_BACK) {
moveTaskToBack(true);
}
return super.onKeyDown(keycode, event);
}
公共类devicedetailsActivity扩展了AppCompativeActivity{
公共最终静态字符串EXTRA_MESSAGE=“MESSAGE”;
私有ListView obj;
DBHelper mydb;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.devicedetails\U布局);
全屏调用();
mydb=新的DBHelper(this);
ArrayList数组_list=mydb.getAllCotacts();
ArrayAdapter ArrayAdapter=新的ArrayAdapter(这个,R.layout.simple\u list\u item\u 1,array\u list);
obj=(ListView)findViewById(R.id.listView1);
对象设置适配器(阵列适配器);
obj.setOnItemClickListener(新的AdapterView.OnItemClickListener(){
@凌驾
公共视图单击(AdapterView arg0、视图arg1、整型arg2、长型arg3){
//TODO自动生成的方法存根
int id_To_Search=arg2+1;
Bundle-dataBundle=新Bundle();
dataBundle.putInt(“id”,id到搜索);
Intent Intent=new Intent(getApplicationContext(),DetailsActivity.class);
意向。额外支出(数据绑定);
星触觉(意向);
}
});
}
公共空全屏调用(){
如果(Build.VERSION.SDK_INT>11&&Build.VERSION.SDK_INT<19){//lower api
int mUIFlag=View.SYSTEM\u UI\u FLAG\u LOW\u PROFILE
|View.SYSTEM\u UI\u FLAG\u HIDE\u导航
|View.SYSTEM\u UI\u FLAG\u全屏显示;
getWindow().getDecorView().SetSystemActivity(mUIFlag);
}else if(Build.VERSION.SDK_INT>=19){
//对于新的api版本。
View decorView=getWindow().getDecorView();
int uiOptions=View.SYSTEM\u UI\u FLAG\u HIDE\u导航
|View.SYSTEM\u UI\u FLAG\u沉浸式\u粘性
|View.SYSTEM\u UI\u FLAG\u全屏显示;
decorView.设置系统兼容性(uiOptions);
}
}
@凌驾
公共布尔onCreateOptions菜单(菜单){
//为菜单充气;这会将项目添加到操作栏(如果存在)。
getMenuInflater().充气(右菜单菜单菜单主菜单);
getMenuInflater().充气(R.menu.home,menu);
返回true;
}
@凌驾
公共布尔值onOptionsItemSelected(菜单项项){
super.onOptionsItemSelected(项目);
开关(item.getItemId()){
案例R.id.item1:Bundle-dataBundle=new Bundle();
dataBundle.putInt(“id”,0);
Intent Intent=new Intent(getApplicationContext(),DetailsActivity.class);
意向。额外支出(数据绑定);
星触觉(意向);
返回true;
案例R.id.item2:dataBundle=newbundle();
dataBundle.putInt(“id”,0);
intent=newintent(getApplicationContext(),MainActivity.class);
意向。额外支出(数据绑定);
星触觉(意向);
返回true;
违约:
返回super.onOptionsItemSelected(项目);
}
}
公共布尔onKeyDown(int-keycode,KeyEvent
public class DBHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "MyDBName.db";
public static final String CONTACTS_TABLE_NAME = "contacts";
public static final String CONTACTS_COLUMN_ID = "id";
public static final String CONTACTS_COLUMN_NAME = "name";
private HashMap hp;
public DBHelper(Context context) {
super(context, DATABASE_NAME , null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(
"create table contacts " +
"(id integer primary key, name text)"
);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS contacts");
onCreate(db);
}
public boolean insertContact(String name) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("name", name);
db.insert("contacts", null, contentValues);
return true;
}
public Cursor getData(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor res = db.rawQuery( "select * from contacts where id="+id+"", null );
return res;
}
public int numberOfRows(){
SQLiteDatabase db = this.getReadableDatabase();
int numRows = (int) DatabaseUtils.queryNumEntries(db, CONTACTS_TABLE_NAME);
return numRows;
}
public boolean updateContact(Integer id, String name) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("name", name);
db.update("contacts", contentValues, "id = ? ", new String[] { Integer.toString(id) } );
return true;
}
public Integer deleteContact (Integer id) {
SQLiteDatabase db = this.getWritableDatabase();
return db.delete("contacts",
"id = ? ",
new String[] { Integer.toString(id) });
}
public ArrayList<String> getAllCotacts() {
ArrayList<String> array_list = new ArrayList<String>();
//hp = new HashMap();
SQLiteDatabase db = this.getReadableDatabase();
Cursor res = db.rawQuery( "select * from contacts", null );
res.moveToFirst();
while(res.isAfterLast() == false){
array_list.add(res.getString(res.getColumnIndex(CONTACTS_COLUMN_NAME)));
res.moveToNext();
}
return array_list;
}
public class devicedetailsActivity extends AppCompatActivity {
public final static String EXTRA_MESSAGE = "MESSAGE";
private ListView obj;
DBHelper mydb;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.devicedetails_layout);
FullScreencall();
mydb = new DBHelper(this);
ArrayList array_list = mydb.getAllCotacts();
ArrayAdapter arrayAdapter=new ArrayAdapter(this,R.layout.simple_list_item_1, array_list);
obj = (ListView)findViewById(R.id.listView1);
obj.setAdapter(arrayAdapter);
obj.setOnItemClickListener(new AdapterView.OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,long arg3) {
// TODO Auto-generated method stub
int id_To_Search = arg2 + 1;
Bundle dataBundle = new Bundle();
dataBundle.putInt("id", id_To_Search);
Intent intent = new Intent(getApplicationContext(),DetailsActivity.class);
intent.putExtras(dataBundle);
startActivity(intent);
}
});
}
public void FullScreencall() {
if(Build.VERSION.SDK_INT > 11 && Build.VERSION.SDK_INT < 19) { // lower api
int mUIFlag = View.SYSTEM_UI_FLAG_LOW_PROFILE
| View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_FULLSCREEN;
getWindow().getDecorView().setSystemUiVisibility(mUIFlag);
} else if(Build.VERSION.SDK_INT >= 19) {
//for new api versions.
View decorView = getWindow().getDecorView();
int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
| View.SYSTEM_UI_FLAG_FULLSCREEN;
decorView.setSystemUiVisibility(uiOptions);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
getMenuInflater().inflate(R.menu.home, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item){
super.onOptionsItemSelected(item);
switch(item.getItemId()) {
case R.id.item1:Bundle dataBundle = new Bundle();
dataBundle.putInt("id", 0);
Intent intent = new Intent(getApplicationContext(),DetailsActivity.class);
intent.putExtras(dataBundle);
startActivity(intent);
return true;
case R.id.item2: dataBundle = new Bundle();
dataBundle.putInt("id", 0);
intent = new Intent(getApplicationContext(),MainActivity.class);
intent.putExtras(dataBundle);
startActivity(intent);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public boolean onKeyDown(int keycode, KeyEvent event) {
if (keycode == KeyEvent.KEYCODE_BACK) {
moveTaskToBack(true);
}
return super.onKeyDown(keycode, event);
}
public class DetailsActivity extends AppCompatActivity {
int from_Where_I_Am_Coming = 0;
private DBHelper mydb ;
TextView name ;
int id_To_Update = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.details);
FullScreencall();
name = (TextView) findViewById(R.id.editTextName);
mydb = new DBHelper(this);
Bundle extras = getIntent().getExtras();
if(extras !=null) {
int Value = extras.getInt("id");
if(Value>0){
//means this is the view part not the add contact part.
Cursor rs = mydb.getData(Value);
id_To_Update = Value;
rs.moveToFirst();
String nam = rs.getString(rs.getColumnIndex(DBHelper.CONTACTS_COLUMN_NAME));
if (!rs.isClosed()) {
rs.close();
}
Button b = (Button)findViewById(R.id.button1);
b.setVisibility(View.INVISIBLE);
name.setText((CharSequence)nam);
name.setFocusable(false);
name.setClickable(false);
}
}
}
public void FullScreencall() {
if(Build.VERSION.SDK_INT > 11 && Build.VERSION.SDK_INT < 19) { // lower api
int mUIFlag = View.SYSTEM_UI_FLAG_LOW_PROFILE
| View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_FULLSCREEN;
getWindow().getDecorView().setSystemUiVisibility(mUIFlag);
} else if(Build.VERSION.SDK_INT >= 19) {
//for new api versions.
View decorView = getWindow().getDecorView();
int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
| View.SYSTEM_UI_FLAG_FULLSCREEN;
decorView.setSystemUiVisibility(uiOptions);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
Bundle extras = getIntent().getExtras();
if(extras !=null) {
int Value = extras.getInt("id");
if(Value>0){
getMenuInflater().inflate(R.menu.display_contact, menu);
} else{
getMenuInflater().inflate(R.menu.back, menu);
}
}
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
super.onOptionsItemSelected(item);
switch(item.getItemId()) {
case R.id.Edit_Contact:
Button b = (Button)findViewById(R.id.button1);
b.setVisibility(View.VISIBLE);
name.setEnabled(true);
name.setFocusableInTouchMode(true);
name.setClickable(true);
return true;
case R.id.Delete_Contact:
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage(R.string.deleteContact)
.setPositiveButton(R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
mydb.deleteContact(id_To_Update);
Toast.makeText(getApplicationContext(), "Deleted Successfully",
Toast.LENGTH_SHORT).show();
Intent intent = new Intent(getApplicationContext(),devicedetailsActivity.class);
startActivity(intent);
}
})
.setNegativeButton(R.string.no, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// User cancelled the dialog
}
});
AlertDialog d = builder.create();
d.setTitle("Are you sure");
d.show();
return true;
case R.id.back:
Intent intent = new Intent(getApplicationContext(),devicedetailsActivity.class);
startActivity(intent);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public void run(View view) {
Bundle extras = getIntent().getExtras();
if(extras !=null) {
int Value = extras.getInt("id");
if(Value>0){
if(mydb.updateContact(id_To_Update,name.getText().toString()
)){
Toast.makeText(getApplicationContext(), "Updated", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(getApplicationContext(),devicedetailsActivity.class);
startActivity(intent);
} else{
Toast.makeText(getApplicationContext(), "not Updated", Toast.LENGTH_SHORT).show();
}
} else{
if(mydb.insertContact(name.getText().toString())){
Toast.makeText(getApplicationContext(), "done",
Toast.LENGTH_SHORT).show();
} else{
Toast.makeText(getApplicationContext(), "not done",
Toast.LENGTH_SHORT).show();
}
Intent intent = new Intent(getApplicationContext(),devicedetailsActivity.class);
startActivity(intent);
}
}
}
name = (TextView) findViewById(R.id.editTextName);
mydb = new DBHelper(this);
Bundle extras = getIntent().getExtras();
if(extras !=null) {
int Value = extras.getInt("id");
if(Value>0){
//means this is the view part not the add contact part.
Cursor rs = mydb.getData(Value);
//Check if cursor has value
if(rs != null && rs.getCount() > 0){
id_To_Update = Value;
rs.moveToFirst();
String nam = rs.getString(rs.getColumnIndex(DBHelper.CONTACTS_COLUMN_NAME));
if (!rs.isClosed()) {
rs.close();
}
Button b = (Button)findViewById(R.id.button1);
b.setVisibility(View.INVISIBLE);
name.setText((CharSequence)nam);
name.setFocusable(false);
name.setClickable(false);
}
}
}
if(extras !=null) {
int Value = extras.getInt("id");
if(Value>0){
//means this is the view part not the add contact part.
Cursor rs = mydb.getData(Value);
if(rs.moveToFirst()) {
id_To_Update = Value;
rs.moveToFirst();
String nam = rs.getString(rs.getColumnIndex(DBHelper.CONTACTS_COLUMN_NAME));
Button b = (Button)findViewById(R.id.button1);
b.setVisibility(View.INVISIBLE);
name.setText((CharSequence)nam);
name.setFocusable(false);
name.setClickable(false);
}
if (!rs.isClosed()) {
rs.close();
}
}
}