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| package com.example.sqlite;
import com.example.sqlite.db.DataBaseHelper;
import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends Activity {
private Button createDBButton ;
private Button insertDBButton ;
private Button updateDBButton ;
private Button queryDBButton ;
private Button deleteDBButton ;
private EditText input_id ;
private EditText input_name ;
private TextView test ;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//此处为创建数据库， 通过按钮监听器来实现
createDBButton = (Button) findViewById(R.id.creatDB);
createDBButton.setOnClickListener(new CreateDBListener());
//此处为插入数据到数据库中
insertDBButton = (Button) findViewById(R.id.insert);
insertDBButton.setOnClickListener(new InsertListener());
//此处为更新数据表
updateDBButton = (Button) findViewById(R.id.update);
updateDBButton.setOnClickListener(new updateListener());
//此处为更新数据表
queryDBButton = (Button) findViewById(R.id.query);
queryDBButton.setOnClickListener(new queryListener());
//此处为删除数据内容
deleteDBButton = (Button) findViewById(R.id.delete);
deleteDBButton.setOnClickListener(new deleteListener());
//此处为显示查询结果
test = (TextView) findViewById(R.id.result);
test.setText("name") ;
//此处为添加数据的选项
//input_id = (EditText) findViewById(R.id.input_id);
//input_name = (EditText) findViewById(R.id.input_name);
}
class CreateDBListener implements OnClickListener{
@Override
public void onClick(View v) {
// 此处为调用另外一个类中的方法来创建数据库， 或者直接来创建数据库
String db_name = "test_mars_db_one" ;
System.out.println("Create");
DataBaseHelper dbHelper = new DataBaseHelper(MainActivity.this, db_name) ;
SQLiteDatabase db = dbHelper.getReadableDatabase() ;
}
}
class InsertListener implements OnClickListener{
@Override
public void onClick(View v) {
//生成一个ContentValues对象
ContentValues values = new ContentValues() ;
//想该对象当中插入键值对，其中键是列名，值是希望插入到这列的值，值必须
values.put("id", 1) ;
values.put("name", "zhangsan") ;
System.out.println("Insert");
DataBaseHelper dbHelper = new DataBaseHelper(MainActivity.this, "test_mars_db_one") ;
SQLiteDatabase db = dbHelper.getWritableDatabase() ;
//调用insert方法， 就可以将数据插入到数据库中
db.insert("user", null, values) ;
}
}
class updateListener implements OnClickListener{
@Override
public void onClick(View arg0) {
// 此处为更新数据内容
System.out.println("Update");
DataBaseHelper dbHelper = new DataBaseHelper(MainActivity.this, "test_mars_db_one") ;
SQLiteDatabase db = dbHelper.getWritableDatabase() ;
ContentValues values = new ContentValues() ;
values.put("name", "zhangsanfeng") ;
//第一个参数为要更新的表名
//第二个参数为一个ContentValues对象
//第三个参数是where语句
db.update("user", values, "id=?", new String[]{"1"}) ;
}
}
class queryListener implements OnClickListener{
@Override
public void onClick(View v) {
// 此处为查询数据内容， 并用到cursor来实现
System.out.println("query");
DataBaseHelper dbHelper = new DataBaseHelper(MainActivity.this, "test_mars_db_one") ;
SQLiteDatabase db = dbHelper.getWritableDatabase() ;
Cursor cursor = db.query("user", new String[]{"id","name"}, "id=?", new String[]{"2"},null,null,null,null) ;
while(cursor.moveToNext()){
String name = cursor.getString(cursor.getColumnIndex("name")) ;
System.out.print("query---> " + name) ;
//name += name ;
test.setText(name) ;
}
}
}
class deleteListener implements OnClickListener{
public void onClick(View v) {
//此处为实现删除数据
System.out.println("delete");
DataBaseHelper dbHelper = new DataBaseHelper(MainActivity.this, "test_mars_db_one") ;
SQLiteDatabase db = dbHelper.getWritableDatabase() ;
//删除特定条件的数据
//db.delete("user","id=?",new String[]{"2"});
//删除所有数据
db.delete("user",null,null);
}
}
}
|
