查看/写入数据库SQLite时发生java致命异常？
当我运行emulator并尝试开始读取或查看数据库时，出现错误
请在本页底部查看我的日志
我有一个数据库活动、一个SQLView活动和一个SQLite活动
数据库活动是运行数据库，SQLView活动是查看数据库，最后一个，mysqlite活动是wrie到我的数据库
我使用SQLiteAssetHelper和我的。rar文件位于my assets/databases/Voedsel中。拉尔
以下是我的活动：
我的数据库活动：
package com.jacob.eindproject;
import 安卓.content.ContentValues;
import 安卓.content.Context;
import 安卓.database.Cursor;
import 安卓.database.SQLException;
import 安卓.database.sqlite.SQLiteDatabase;
import 安卓.database.sqlite.SQLiteOpenHelper;
import 安卓.database.sqlite.SQLiteDatabase.CursorFactory;
import java.sql.*;
import com.readystatesoftware.sqliteasset.SQLiteAssetHelper;
public class Database extends SQLiteAssetHelper {
public static final String KEY_PRODUCT = "Product";
public static final String KEY_EENHEID = "Eenheid";
public static final String KEY_KCAL = "Kcal";
private static final String DATABASE_NAME = "Voedsel";
private static final String DATABASE_TABLE = "Voeding";
private static final int DATABASE_VERSION = 1;
private DbHelper ourHelper;
private Context Context;
private SQLiteDatabase ourDatabase;
private static class DbHelper extends SQLiteAssetHelper{
public DbHelper(Context context) {
super(context, DATABASE_NAME, context.getExternalFilesDir(null).getAbsolutePath(), null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
}
}
@Override
public void onUpgrade(SQLiteDatabase Voedsel, int oldVersion, int newVersion) {
Voedsel.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(Voedsel);
}
public Database(Context context){
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public Database open() throws SQLException{
ourHelper = new DbHelper(Context);
ourDatabase = ourHelper.getWritableDatabase();
return this;
}
public void close() {
ourHelper.close();
}
public long createEntry(String product, String kcal, String eenheid) {
ContentValues cv = new ContentValues();
cv.put(KEY_PRODUCT, product);
cv.put(KEY_EENHEID, eenheid);
cv.put(KEY_KCAL, kcal);
return ourDatabase.insert(DATABASE_TABLE, null, cv);
}
public String getData() {
// TODO Auto-generated method stub
String[] columns = new String[]{ KEY_PRODUCT, KEY_EENHEID, KEY_KCAL};
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, null, null, null, null, null);
String result = "";
int iProduct = c.getColumnIndex(KEY_PRODUCT);
int iEenheid = c.getColumnIndex(KEY_EENHEID);
int iKcal = c.getColumnIndex(KEY_KCAL);
for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
result = result + c.getString(iProduct) + " " + c.getString(iEenheid) + " " + c.getString(iKcal) + "\n";
}
return result;
}
public void close(Database database) {
// TODO Auto-generated method stub
}
}
我的SQLite活动：
public class SQLite extends Activity implements View.OnClickListener {
Button sqlUpdate, sqlView;
EditText sqlVoeding, sqlKcal, sqlEenheid;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.sqllite);
sqlUpdate = (Button) findViewById(R.id.bSQLUpdate);
sqlVoeding = (EditText) findViewById(R.id.etSQLVoeding);
sqlEenheid = (EditText) findViewById(R.id.etSQLEenheid);
sqlKcal = (EditText) findViewById(R.id.etSQLKcal);
sqlView = (Button) findViewById(R.id.bSQLopenView);
sqlView.setOnClickListener((安卓.view.View.OnClickListener) this);
sqlUpdate.setOnClickListener((安卓.view.View.OnClickListener) this);
}
public void onClick(View arg0) {
switch (arg0.getId()) {
case R.id.bSQLUpdate:
boolean didItWork = true;
try{
String voeding = sqlVoeding.getText().toString();
String Kcal = sqlKcal.getText().toString();
String eenheid = sqlEenheid.getText().toString();
Database entry = new Database(SQLite.this);
entry.open();
entry.createEntry(voeding, Kcal, eenheid);
entry.close();
}catch (Exception e ){
didItWork = false;
}finally{
if (didItWork){
Dialog d = new Dialog(this);
d.setTitle("Heak Yeay");
TextView tv = new TextView(this);
tv.setText("Succes");
d.setContentView(tv);
d.show();
}
}
break;
case R.id.bSQLopenView:
Intent i = new Intent(this, SQLView.class);
startActivity(i);
}
}
public void onClick(DialogInterface arg0, int arg1) {
// TODO Auto-generated method stub
}
}
以及SQLView活动：
public class SQLView extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.sqlview);
TextView tv = (TextView) findViewById(R.id.tvSQLinfo);
Database info = new Database(this);
info.open();
String data = info.getData();
info.close();
tv.setText(data);
}
}
这是我单击SQLView活动时的logcat错误：
12-16 14:28:26.883: E/AndroidRuntime(1170): FATAL EXCEPTION: main
12-16 14:28:26.883: E/AndroidRuntime(1170): java.lang.NoClassDefFoundError: com.jacob.eindproject.Database
12-16 14:28:26.883: E/AndroidRuntime(1170): at com.jacob.eindproject.SQLView.onCreate(SQLView.java:14)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.app.Activity.performCreate(Activity.java:5133)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.app.ActivityThread.access$600(ActivityThread.java:141)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.os.Handler.dispatchMessage(Handler.java:99)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.os.Looper.loop(Looper.java:137)
12-16 14:28:26.883: E/AndroidRuntime(1170): at 安卓.app.ActivityThread.main(ActivityThread.java:5103)
12-16 14:28:26.883: E/AndroidRuntime(1170): at java.lang.reflect.Method.invokeNative(Native Method)
12-16 14:28:26.883: E/AndroidRuntime(1170): at java.lang.reflect.Method.invoke(Method.java:525)
12-16 14:28:26.883: E/AndroidRuntime(1170): at com.安卓.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
12-16 14:28:26.883: E/AndroidRuntime(1170): at com.安卓.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-16 14:28:26.883: E/AndroidRuntime(1170): at dalvik.system.NativeStart.main(Native Method)
这是我单击“写入”活动时的错误：
12-16 14:27:35.913: E/AndroidRuntime(999): FATAL EXCEPTION: main
12-16 14:27:35.913: E/AndroidRuntime(999): java.lang.NoClassDefFoundError: com.jacob.eindproject.Database
12-16 14:27:35.913: E/AndroidRuntime(999): at com.jacob.eindproject.SQLite.onClick(SQLite.java:45)
12-16 14:27:35.913: E/AndroidRuntime(999): at 安卓.view.View.performClick(View.java:4240)
12-16 14:27:35.913: E/AndroidRuntime(999): at 安卓.view.View$PerformClick.run(View.java:17721)
12-16 14:27:35.913: E/AndroidRuntime(999): at 安卓.os.Handler.handleCallback(Handler.java:730)
12-16 14:27:35.913: E/AndroidRuntime(999): at 安卓.os.Handler.dispatchMessage(Handler.java:92)
12-16 14:27:35.913: E/AndroidRuntime(999): at 安卓.os.Looper.loop(Looper.java:137)
12-16 14:27:35.913: E/AndroidRuntime(999): at 安卓.app.ActivityThread.main(ActivityThread.java:5103)
12-16 14:27:35.913: E/AndroidRuntime(999): at java.lang.reflect.Method.invokeNative(Native Method)
12-16 14:27:35.913: E/AndroidRuntime(999): at java.lang.reflect.Method.invoke(Method.java:525)
12-16 14:27:35.913: E/AndroidRuntime(999): at com.安卓.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
12-16 14:27:35.913: E/AndroidRuntime(999): at com.安卓.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-16 14:27:35.913: E/AndroidRuntime(999): at dalvik.system.NativeStart.main(Native Method)
希望有人能帮我纠正错误。提前感谢大家抽出时间
雅各布
# 1 楼答案
我认为您没有正确地将SQLiteAssetThelper库添加到项目中。 必须确保项目的生成路径正确，并且选择了所有引用的库
右键单击项目并选择“属性”
点击“安卓”
确保选择了SQLITeAsselPer库