这是数据库
package com.example.sama;
import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.DatabaseErrorHandler;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
public class Database extends Activity {
public static final String KEY_ROWID ="_id";
public static final String KEY_NAME ="Bills_name";
public static final String KEY_MAXAMOUNT ="_";
public static final String KEY_REMAIN ="what_is_left";
private static final String DATABASE_NAME ="SAMA";
private static final String DATABASE_TABLE ="gg";
private static final int DATABASE_VERSION = 1;
private DBhelper ourHelper;
private final Context ourContext;
private SQLiteDatabase ourDatabase;
public static class DBhelper extends SQLiteOpenHelper{
public DBhelper(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("CREATE TABLE " + DATABASE_TABLE +" (" +
KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_NAME + " TEXT NOT NULL, " +
KEY_MAXAMOUNT + " INTEGER NOT NULL , " +
KEY_REMAIN + " INTEGER );"
);
}
@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);
}
}
public Database(Context c){
ourContext = c ;
}
public Database open() throws SQLException
{
ourHelper = new DBhelper(ourContext);
ourDatabase = ourHelper.getWritableDatabase();
return this;
}
public void close(){
ourHelper.close();
}
public long creatEntry(String name, String maxamount) {
// TODO Auto-generated method stub
ContentValues cv = new ContentValues();
cv.put(KEY_NAME, name);
cv.put(KEY_MAXAMOUNT, maxamount);
return ourDatabase.insert(DATABASE_TABLE, null, cv);
}
public String getData() {
// TODO Auto-generated method stub
String[] columns = new String[]{KEY_ROWID, KEY_NAME ,KEY_MAXAMOUNT,KEY_REMAIN };
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, null, null, null, null, null);
String result ="";
int iROW =c.getColumnIndex(KEY_ROWID);
int iNAME =c.getColumnIndex(KEY_NAME);
int iMAXAMOUNT =c.getColumnIndex(KEY_MAXAMOUNT);
int iREMAIN =c.getColumnIndex(KEY_REMAIN);
for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
result = result + c.getString(iROW) + " " + c.getString(iNAME) + " " +c.getString(iMAXAMOUNT) + " " + c.getString(iREMAIN) +"\n ";
}
return result;
}
}
这是新的字段代码，当我尝试从我正在创建的应用程序向数据库中添加一些内容时，它说它无法创建表，而代码假设是自己创建表的任何人都知道出了什么问题，谢谢你时间
`package com.example.sama;
import android.app.Activity;
import android.app.Dialog;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class newfield extends Activity implements OnClickListener {
Button save,cancel;
EditText maxAmount,FieldName;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.newfield);
maxAmount = (EditText) findViewById(R.id.maxAmount);
FieldName = (EditText) findViewById(R.id.FieldName);
save = (Button) findViewById(R.id.SQLsave);
cancel = (Button) findViewById(R.id.SQLcancel);
save.setOnClickListener(this);
cancel.setOnClickListener(this);
}
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
switch (arg0.getId()){
case R.id.SQLsave:
boolean didItWork = true ;
try{
String name = FieldName.getText().toString();
String maxamount = maxAmount.getText().toString();
Database entry = new Database(newfield.this);
entry.open();
entry.creatEntry(name, maxamount);
entry.close();
}catch (Exception e ){
didItWork = false ;
Dialog d = new Dialog(newfield.this );
d.setTitle("doneeee !");
TextView tv =new TextView(newfield.this);
tv.setText("sucsses");
d.setContentView(tv);
d.show();
}finally{
if (didItWork){
Dialog d = new Dialog(newfield.this );
d.setTitle("done !");
TextView tv =new TextView(newfield.this);
tv.setText("sucsses");
d.setContentView(tv);
d.show();
Intent i = new Intent (newfield.this,MainActivity.class);
startActivity(i);
}
}
break;
case R.id.SQLcancel:
finish();
break;
}
}
}