MainActiviy.java

package com.example.sqllitcache; import android.app.Activity; import android.app.AlertDialog; import android.content.ContentValues; import android.content.DialogInterface; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.AdapterView.OnItemLongClickListener; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.EditText; import android.widget.ListView; import android.widget.Toast; public class MainActivity extends Activity { ListView lv; Button submit; EditText et; SQLiteDatabase dbwrite ; Dbhelper dbhelper; ArrayAdapter <String> adapter; Cursor c; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); lv=(ListView) findViewById(R.id.listView1); submit=(Button) findViewById(R.id.button1); et=(EditText) findViewById(R.id.autoCompleteTextView1); adapter=new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1); lv.setAdapter(adapter); dbhelper=new Dbhelper(this); dbwrite=dbhelper.getWritableDatabase(); getData(); //点击提交 submit.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub String newData=et.getText().toString(); addData(newData); } }); //长按列表项，修改数据 lv.setOnItemLongClickListener(new OnItemLongClickListener() { @Override public boolean onItemLongClick(AdapterView<?> arg0, View arg1, final int position, long arg3) { // TODO Auto-generated method stub new AlertDialog.Builder(MainActivity.this).setPositiveButton("我确定修改",new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // TODO Auto-generated method stub updateData(position); } }).show(); return false; } }); //短按列表项删除数据 lv.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) { // TODO Auto-generated method stub Toast.makeText(MainActivity.this, position+"", 0).show(); deleteData(position); } }); } //添加数据的执行函数，添加到本地数据库，并提示更新listtview void addData(String newData) { //添加到本地数据库 ContentValues content=new ContentValues(); String putdata=et.getText().toString(); content.put("data", putdata); dbwrite.insert("datatable",null, content); getData(); } //删除一条数据 void deleteData(int position) { c.moveToPosition(position); int id=c.getInt(c.getColumnIndex("_id")); dbwrite.delete("datatable", "_id=http://www.it165.net/database/html/201501/?", new String[]{id+""} ); getData(); } //修改一条数据 void updateData(int position) { c.moveToPosition(position); ContentValues cv=new ContentValues(); cv.put("data", "changed"); int id=c.getInt(c.getColumnIndex("_id")); dbwrite.update("datatable", cv, "_id=http://www.it165.net/database/html/201501/?", new String [] {id+""}); getData(); } //获取数据 void getData() { c= dbwrite.query("datatable", null, null, null, null, null, null); adapter.clear(); //读取本地数据库 while(c.moveToNext()) { String data=c.getString(c.getColumnIndex("data")); int id=c.getInt(c.getColumnIndex("_id")); adapter.add(data+":"+id); System.out.println(data+": "+id); } adapter.notifyDataSetChanged(); } }

Dbhelper.java

package com.example.sqllitcache; import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteDatabase.CursorFactory; import android.database.sqlite.SQLiteOpenHelper; public class Dbhelper extends SQLiteOpenHelper { public Dbhelper(Context context ) { super(context, "mydb",null, 1); // TODO Auto-generated constructor stub } @Override public void onCreate(SQLiteDatabase db) { // TODO Auto-generated method stub db.execSQL("CREATE TABLE datatable ("+ "_id INTEGER PRIMARY KEY AUTOINCREMENT,"+ "data String DEFAULT "")" ); } @Override public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) { // TODO Auto-generated method stub } }