/** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main);
Button.OnClickListener btn=new Button.OnClickListener(){ @Override public void onClick(View v) { // TODO Auto-generated method stub switch(v.getId()){ case R.id.btn1:insertItem();break; case R.id.btn2:deleteItem();break; case R.id.btn3:queryItem();break; case R.id.btn4:deleteTable();break; case R.id.btn5:replaceTable();break; } } private void replaceTable() { // TODO Auto-generated method stub
} private void deleteTable() { // TODO Auto-generated method stub
} private void queryItem() { // TODO Auto-generated method stub
} private void deleteItem() { // TODO Auto-generated method stub
mOpenHelper 这个是自己写的类
一般都会自己写个类继承 SqliteOpenHelper最好日志发全了 这样能帮你分析是什么问题
package com.handson.sql;import android.app.Activity;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;public class TestSql extends Activity {
private Button btn1,btn2,btn3,btn4,btn5;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btn1=(Button)this.findViewById(R.id.btn1);
btn2=(Button)this.findViewById(R.id.btn2);
btn1=(Button)this.findViewById(R.id.btn3);
btn2=(Button)this.findViewById(R.id.btn4);
btn2=(Button)this.findViewById(R.id.btn5);
Button.OnClickListener btn=new Button.OnClickListener(){ @Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch(v.getId()){
case R.id.btn1:insertItem();break;
case R.id.btn2:deleteItem();break;
case R.id.btn3:queryItem();break;
case R.id.btn4:deleteTable();break;
case R.id.btn5:replaceTable();break;
}
} private void replaceTable() {
// TODO Auto-generated method stub
} private void deleteTable() {
// TODO Auto-generated method stub
} private void queryItem() {
// TODO Auto-generated method stub
} private void deleteItem() {
// TODO Auto-generated method stub
} private void insertItem() {
// TODO Auto-generated method stub
SQLiteDatabase db=mOpenHelper.getWritableDatabse();
}
};
btn1.setOnClickListener(btn);
btn2.setOnClickListener(btn);
btn3.setOnClickListener(btn);
btn4.setOnClickListener(btn);
btn5.setOnClickListener(btn);
}
private static class DatabaseHelper extends SQLiteOpenHelper{ public DatabaseHelper(Context context, String name,
CursorFactory factory, int version) {
super(context, name, factory, version);
// TODO Auto-generated constructor stub
} @Override
public void onCreate(SQLiteDatabase sd) {
// TODO Auto-generated method stub
//sql语句
String sql="create table dairy (title ,body);";
Log.i("haiyang:Create DB=",sql);
//执行sql语句
sd.execSQL(sql);
} @Override
public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
// TODO Auto-generated method stub
}
}
}
SQLiteDatabase db=mOpenHelper.getWritableDatabse();
总是引用不到???请大虾帮忙???
编译能过?
改为
SQLiteDatabase db=new DatabaseHelper(this,xxx,xxx,xxx).getWritableDatabse();
这个是java语言问题 和android 无关
其次 copy过来的代码 要自己仔细读读
SQLiteDatabase db=new DatabaseHelper(this,xxx,xxx,xxx).getWritableDatabse();
功能一样吗??
mOpenHelper = new DatabaseHelper(this,DB_NAME,null,DB_VERSION);