小弟初学安卓编程,在学数据库的东西,但是下面的程序放在安卓模拟器上的时候老是提示“已停止工作”,不知道哪里有问题,贴上程序代码和数据库代码
程序代码:
package com.demo.android.dummynote;import android.app.ListActivity;
import android.database.Cursor;
import android.os.Bundle;
import android.widget.SimpleCursorAdapter;public class DummyNote extends ListActivity {
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setAdapter();
}private NotesDbAdapter mDbHelper;
private Cursor mNotesCursor;private void setAdapter(){
mDbHelper = new NotesDbAdapter(this);
mDbHelper.open();
fillData();
}private void fillData(){
mNotesCursor = mDbHelper.getall();
startManagingCursor(mNotesCursor);
String[] from = new String[]{"tname","ttel"};
int[] to = new int[] {android.R.id.text1, android.R.id.text2};
SimpleCursorAdapter adapter =
new SimpleCursorAdapter(this,android.R.layout.simple_list_item_1,mNotesCursor,from,to);
setListAdapter(adapter);
}
}
数据库代码:
package com.demo.android.dummynote;import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;public class NotesDbAdapter{
private static final String DATABASE_NAME = "notes.db";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_TABLE ="notes";
private static final String DATABASE_CREATE =
"create table notes("
+"_id INTEGER PRIMARY KEY,"
+"note TEXT,"
+"created INTEGER,"
+"modified INTEGER"
+");";
private static class DatabaseHelper extends SQLiteOpenHelper{ public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
} @Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL(DATABASE_CREATE);
} @Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS "+DATABASE_TABLE);
onCreate(db);
}
}
private Context mCtx = null;
private DatabaseHelper dbHelper;
private SQLiteDatabase db;
public NotesDbAdapter(Context ctx){
this.mCtx = ctx;
}
public NotesDbAdapter open() throws SQLException{
dbHelper = new DatabaseHelper(mCtx);
db = dbHelper.getWritableDatabase();
return this;
}
public void close(){
dbHelper.close();
}
public Cursor getall(){
return db.rawQuery("SELECT * FROM notes",null);
}
}本人毕业设计做的程序要数据库,所以好心人帮下忙哈,先感谢一下
程序代码:
package com.demo.android.dummynote;import android.app.ListActivity;
import android.database.Cursor;
import android.os.Bundle;
import android.widget.SimpleCursorAdapter;public class DummyNote extends ListActivity {
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setAdapter();
}private NotesDbAdapter mDbHelper;
private Cursor mNotesCursor;private void setAdapter(){
mDbHelper = new NotesDbAdapter(this);
mDbHelper.open();
fillData();
}private void fillData(){
mNotesCursor = mDbHelper.getall();
startManagingCursor(mNotesCursor);
String[] from = new String[]{"tname","ttel"};
int[] to = new int[] {android.R.id.text1, android.R.id.text2};
SimpleCursorAdapter adapter =
new SimpleCursorAdapter(this,android.R.layout.simple_list_item_1,mNotesCursor,from,to);
setListAdapter(adapter);
}
}
数据库代码:
package com.demo.android.dummynote;import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;public class NotesDbAdapter{
private static final String DATABASE_NAME = "notes.db";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_TABLE ="notes";
private static final String DATABASE_CREATE =
"create table notes("
+"_id INTEGER PRIMARY KEY,"
+"note TEXT,"
+"created INTEGER,"
+"modified INTEGER"
+");";
private static class DatabaseHelper extends SQLiteOpenHelper{ public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
} @Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL(DATABASE_CREATE);
} @Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS "+DATABASE_TABLE);
onCreate(db);
}
}
private Context mCtx = null;
private DatabaseHelper dbHelper;
private SQLiteDatabase db;
public NotesDbAdapter(Context ctx){
this.mCtx = ctx;
}
public NotesDbAdapter open() throws SQLException{
dbHelper = new DatabaseHelper(mCtx);
db = dbHelper.getWritableDatabase();
return this;
}
public void close(){
dbHelper.close();
}
public Cursor getall(){
return db.rawQuery("SELECT * FROM notes",null);
}
}本人毕业设计做的程序要数据库,所以好心人帮下忙哈,先感谢一下
这tname和ttel这两个字段在哪呢?
程序能运行了,但是没有出现任何东西,就是一片黑而已,不知道怎么解决,