我有一个将一些数据(9 列)存储到 SQLite 数据库的应用程序。我遵循了vogella的示例,并用其他一些示例对其进行了调整,直到我认为它应该没问题。现在,我为使我的应用程序运行而苦苦挣扎了两天,但发现自己陷入了 SQLite 错误,最近又遇到了这个错误:无法从具有 1 行 1 列的 CursorWindow 读取第 0 行第 4 列。当我尝试在向 DB 添加任何内容之前首先打开活动 ure .java 时出现错误(但我认为之前的尝试中已经有一些数据)。
这是我的 VnosiDB.java 的代码:
package com.sandpit.jazstudent;
public class VnosiDB {
private long _id;
private int odT;
private int deltaT;
private String niz;
private String delo;
private int post;
private int dod;
private String opis;
private int vnos;
public long getId() {
return _id;
}
public void setId(long _id) {
this._id = _id;
}
public int getOdt() {
return odT;
}
public void setOdt(int odT) {
this.odT = odT;
}
public int getDeltat() {
return deltaT;
}
public void setDeltat(int deltaT) {
this.deltaT = deltaT;
}
public String getNiz() {
return niz;
}
public void setNiz(String niz) {
this.niz = niz;
}
public String getDelo() {
return delo;
}
public void setDelo(String delo) {
this.delo = delo;
}
public int getPost() {
return post;
}
public void setPost(int post) {
this.post = post;
}
public int getDod() {
return dod;
}
public void setDod(int dod) {
this.dod = dod;
}
public String getOpis() {
return opis;
}
public void setOpis(String opis) {
this.opis = opis;
}
public int getVnos() {
return vnos;
}
public void setVnos(int vnos) {
this.vnos = vnos;
}
// Will be used by the ArrayAdapter in the ListView
@Override
public String toString() {
return delo;
}
我的 DatabaseManidzer.java:
package com.sandpit.jazstudent;
import android.content.Context;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DatabaseManidzer extends SQLiteOpenHelper {
public static final String TABLE_VNOSI = "vnosi";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_ODT = "odT";
public static final String COLUMN_DELTAT = "deltaT";
public static final String COLUMN_NIZ = "niz";
public static final String COLUMN_DELO = "delo";
public static final String COLUMN_POST = "post";
public static final String COLUMN_DOD = "dod";
public static final String COLUMN_OPIS = "opis";
public static final String COLUMN_VNOS = "vnos";
private static final String DATABASE_NAME = "dbvnosi.db";
private static final int DATABASE_VERSION = 1;
// database creation sql statement
private static final String DATABASE_CREATE = "CREATE TABLE vnosi (_id INTEGER PRIMARY KEY, odT NUMERIC, deltaT NUMERIC, niz TEXT, delo TEXT, post NUMERIC, dod NUMERIC, opis TEXT, vnos NUMERIC);";
public DatabaseManidzer(Context context){
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase database){
try{
database.execSQL(DATABASE_CREATE);
} catch (SQLException e){
e.printStackTrace();
}
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
Log.w(DatabaseManidzer.class.getName(),"Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS " + TABLE_VNOSI);
onCreate(db);
}
}
我的 VnosiDataSource.java:
package com.sandpit.jazstudent;
import java.util.ArrayList;
import java.util.List;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
public class VnosiDataSource {
// Database fields
private SQLiteDatabase database;
private DatabaseManidzer dbHelper;
private String[] allColumns = { DatabaseManidzer.COLUMN_ID,
DatabaseManidzer.COLUMN_ODT, DatabaseManidzer.COLUMN_DELTAT,
DatabaseManidzer.COLUMN_NIZ, DatabaseManidzer.COLUMN_DELO,
DatabaseManidzer.COLUMN_POST, DatabaseManidzer.COLUMN_DOD,
DatabaseManidzer.COLUMN_OPIS, DatabaseManidzer.COLUMN_VNOS };
public VnosiDataSource(Context context) {
dbHelper = new DatabaseManidzer(context);
}
public void open() throws SQLException {
database = dbHelper.getWritableDatabase();
}
public void close() {
dbHelper.close();
}
public VnosiDB createVnos(int odt, int deltat, String niz, String delo,
int post, int dod, String opis, int vnos) {
ContentValues values = new ContentValues();
values.put(DatabaseManidzer.COLUMN_ODT, odt);
values.put(DatabaseManidzer.COLUMN_DELTAT, deltat);
values.put(DatabaseManidzer.COLUMN_NIZ, niz);
values.put(DatabaseManidzer.COLUMN_DELO, delo);
values.put(DatabaseManidzer.COLUMN_POST, post);
values.put(DatabaseManidzer.COLUMN_DOD, dod);
values.put(DatabaseManidzer.COLUMN_OPIS, opis);
values.put(DatabaseManidzer.COLUMN_VNOS, vnos);
long insertId = database.insert(DatabaseManidzer.TABLE_VNOSI, null,
values);
Cursor cursor = database.query(DatabaseManidzer.TABLE_VNOSI,
allColumns, DatabaseManidzer.COLUMN_ID + " = " + insertId,
null, null, null, null);
cursor.moveToFirst();
VnosiDB newVnos = cursorToVnos(cursor);
cursor.close();
return newVnos;
}
public void deleteVnos(VnosiDB vnos) {
long id = vnos.getId();
System.out.println("Comment deleted with id: " + id);
database.delete(DatabaseManidzer.TABLE_VNOSI,
DatabaseManidzer.COLUMN_ID + " = " + id, null);
}
public List<VnosiDB> getAllDela() {
List<VnosiDB> dela = new ArrayList<VnosiDB>();
Cursor cursor = database.rawQuery("SELECT delo from vnosi", null);
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
VnosiDB curdela = cursorToDela(cursor);
dela.add(curdela);
cursor.moveToNext();
}
// Make sure to close the cursor
cursor.close();
return dela;
}
private VnosiDB cursorToDela(Cursor cursor) {
VnosiDB curdela = new VnosiDB();
curdela.setId(cursor.getLong(0));
curdela.setDelo(cursor.getString(4));
return curdela;
}
private VnosiDB cursorToVnos(Cursor cursor) {
VnosiDB vnos = new VnosiDB();
vnos.setId(cursor.getInt(0));
vnos.setOdt(cursor.getInt(1));
vnos.setDeltat(cursor.getInt(2));
vnos.setNiz(cursor.getString(3));
vnos.setDelo(cursor.getString(4));
vnos.setPost(cursor.getInt(5));
vnos.setDod(cursor.getInt(6));
vnos.setOpis(cursor.getString(7));
vnos.setVnos(cursor.getInt(8));
return vnos;
}
}
最后是一个调用数据库的 Ure.java:
package com.sandpit.jazstudent;
import java.util.List;
import android.annotation.SuppressLint;
import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.util.SparseArray;
import android.view.View;
import android.view.WindowManager;
import android.widget.ArrayAdapter;
import android.widget.TextView;
public class Ure extends ListActivity {
private VnosiDataSource datasource;
SparseArray<Group> groups = new SparseArray<Group>();
@SuppressLint("SdCardPath")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
overridePendingTransition(R.layout.push_left_in, R.layout.push_left_out);
setContentView(R.layout.moje_ure);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
datasource = new VnosiDataSource(this);
datasource.open();
List<VnosiDB> values = datasource.getAllDela();
ArrayAdapter<VnosiDB> adapter = new ArrayAdapter<VnosiDB>(this,
android.R.layout.simple_list_item_1, values);
setListAdapter(adapter);
TextView novVnos = (TextView) findViewById(R.id.novVnosNaslov);
novVnos.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
startActivity(new Intent("com.sandpit.jazstudent.VNOS"));
}
});
}
@Override
protected void onResume() {
datasource.open();
super.onResume();
}
@Override
protected void onPause() {
datasource.close();
super.onPause();
}
public void onBackPressed() {
super.onBackPressed();
overridePendingTransition(R.layout.push_right_in,
R.layout.push_right_out);
}
}
我用这段代码写信给数据库:
shrani = (TextView) findViewById(R.id.shrani);
shrani.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
vnosDB = (int)myCalendar.getTimeInMillis();
datasource.createVnos(zacetekDB, razlikaDB, nizDB, deloDB, postavkaDB, dodatekDB, opisDB, vnosDB);
datasource.close();
Toast test = Toast.makeText(Vnos.this, "Vnos " + deloDB + " uspešen!", Toast.LENGTH_LONG);
test.show();
finish();
}
});
}
错误是:
09-29 20:24:57.360: E/CursorWindow(17150): Failed to read row 0, column 4 from a CursorWindow which has 1 rows, 1 columns.
09-29 20:24:57.360: D/AndroidRuntime(17150): Shutting down VM
09-29 20:24:57.360: W/dalvikvm(17150): threadid=1: thread exiting with uncaught exception (group=0x412be2a0)
09-29 20:24:57.365: E/AndroidRuntime(17150): FATAL EXCEPTION: main
09-29 20:24:57.365: E/AndroidRuntime(17150): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.sandpit.jazstudent/com.sandpit.jazstudent.Ure}: java.lang.IllegalStateException: Couldn't read row 0, col 4 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it.
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2110)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2135)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.ActivityThread.access$700(ActivityThread.java:140)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1237)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.os.Handler.dispatchMessage(Handler.java:99)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.os.Looper.loop(Looper.java:137)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.ActivityThread.main(ActivityThread.java:4921)
09-29 20:24:57.365: E/AndroidRuntime(17150): at java.lang.reflect.Method.invokeNative(Native Method)
09-29 20:24:57.365: E/AndroidRuntime(17150): at java.lang.reflect.Method.invoke(Method.java:511)
09-29 20:24:57.365: E/AndroidRuntime(17150): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1027)
09-29 20:24:57.365: E/AndroidRuntime(17150): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:794)
09-29 20:24:57.365: E/AndroidRuntime(17150): at dalvik.system.NativeStart.main(Native Method)
09-29 20:24:57.365: E/AndroidRuntime(17150): Caused by: java.lang.IllegalStateException: Couldn't read row 0, col 4 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it.
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.database.CursorWindow.nativeGetString(Native Method)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.database.CursorWindow.getString(CursorWindow.java:438)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:51)
09-29 20:24:57.365: E/AndroidRuntime(17150): at com.sandpit.jazstudent.VnosiDataSource.cursorToDela(VnosiDataSource.java:84)
09-29 20:24:57.365: E/AndroidRuntime(17150): at com.sandpit.jazstudent.VnosiDataSource.getAllDela(VnosiDataSource.java:72)
09-29 20:24:57.365: E/AndroidRuntime(17150): at com.sandpit.jazstudent.Ure.onCreate(Ure.java:35)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.Activity.performCreate(Activity.java:5206)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
09-29 20:24:57.365: E/AndroidRuntime(17150): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2074)
09-29 20:24:57.365: E/AndroidRuntime(17150): ... 11 more
希望我提供了解决此问题可能需要的所有代码。感谢你的帮助!谢谢!