2018/6/22 CZ 13:45 c.~
Android
最近在构想，在Android下，如何去完成一个APP，它具有服务器-客户端模式。
服务器上运行SQLite，客户端通过远程访问去获取SQLite数据,进行一系列的访问，增删改查操作。
构想过程:
1.部署服务器模式。使用Android自带的Service组件，可以提供远程服务。
2.部署客户端。使用ServiceConnection 去实现Service的回调Onbind()的方法。
具体过程:
1.Service
在部署服务端时，遇到了几个问题。
1.Service是什么。
扫描二维码关注公众号，回复：
1710380 查看本文章
是android模式下自带的四大组件之一。它跟进程类似。一旦创建，不去销毁，就会一直运行在android的后台。
2.如何创建service
class MyService extends Service{} //继承Service即可
3.如何开启service
------------开启service有两种方法
-----------1.BindService()//unbind（）
bindService 可以使Activity和Service进行数据交换，通信等远程操作。
bindservice(intent,serviceConnection,int falgs) //一般多用于隐式意图
----------2. StartService()//stopservice（）
startservice（intent）//无法进行通信及数据交换
4.activity界面和Remote-service之间是如何进行交互的
private ServiceConnection connection =new ServiceConnection() {
@Override
public void onServiceDisconnected(ComponentName name) {
// TODO 解除连接的操作
//mBound=false;
}
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
// TODO 获取远程Service
Log.d("Client-Service","onServiceConnected");
ist=IStudent.Stub.asInterface(service);
Log.d("ist","学生对象的内存地址="+ist);
}
};
Service---MainActivity部署 直接贴代码
public class MainActivity extends Activity implements OnClickListener{
Button btn1;
Button btn2;
IStudent ist;
boolean mBound=false;
IStudentImpl iStudentImpl;
public static Context context;
//public static SQLiteCreateHelper helper;
private ServiceConnection connection = new ServiceConnection() {
@Override
public void onServiceDisconnected(ComponentName name) {
// TODO Auto-generated method stub
mBound=false;
}
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
// TODO Auto-generated method stub
Log.i("studentInfo","onServiceConnected");
ist=IStudent.Stub.asInterface(service);
Log.i("studentInfo","学生对象内存地址="+ist);
try {
//SQLiteCreateHelper helper =new SQLiteCreateHelper(MainActivity.this);
//sqL.getWritableDatabase();
boolean b =ist.selectID("0112");
Log.d("个人密码:","是否正确="+b);
} catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
mBound=true;
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn1=(Button)findViewById(R.id.button1);
btn2=(Button)findViewById(R.id.button2);
btn1.setOnClickListener(this);
btn2.setOnClickListener(this);
context=MainActivity.this;
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.button1:
Intent intent = new Intent(MainActivity.this,MyService.class);
bindService(intent, connection, BIND_AUTO_CREATE);
break;
case R.id.button2:
if(mBound)
{
unbindService(connection);
mBound=false;
}
break;
default:
break;
}
}
}
Service-SQLite部署//贴代码
public class SQLiteCreateHelper extends SQLiteOpenHelper{
public static Cursor cursor;
public SQLiteCreateHelper(Context context) {
super(context,"subject1.db",null,5);
// TODO Auto-generated constructor stub
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
ContentValues values=new ContentValues();
onOpen(db);
String sysName="root";
String sysID="0112";
String sysPosition="秘书";
String syspassword="123456";
values.put("stuID", sysID);
values.put("stuName", sysName);
values.put("stuPosition", sysPosition);
values.put("stupassword", syspassword);
// TODO Auto-generated method stub
//学生信息表,
db.execSQL("create table stuInfo ( stuID varchar(20) primary key,"+"stuName varchar(20) not null,"
+"stuPosition varchar(50) not null,"+"stupassword varchar(15) not null);");
//教师信息表
db.execSQL("create table teachInfo (teaID varchar(20) not null primary key ,"+"teaName varchar(20) not null ,"
+"teaPosition varchar(50) not null,"+"teapassword varchar(15) not null);");
//管理员信息表
db.execSQL("create table sysInfo ( sysID varchar(20) primary key ,"+"sysName varchar(20) not null ,"
+"sysPosition varchar(50) not null,"+"syspassword varchar(15) not null);");
//课程表信息
db.execSQL("create table subject ( subID varchar(15) primary key ,"+"subName varchar(25) not null,"+"subTotalStu integer );");
//学生选课表+成绩+课堂评价+出勤情况
db.execSQL("create table stuSelectSub ( stuID varchar(20) not null,"+"subID varchar(15) not null,"+"subName varchar(25) not null,"
+"stuPosition varchar(50) not null,"+"commandS1 integer ,"+"commandS2 integer ,"+"commandS3 integer,"+"commandS4 integer,"+"workScroe integer ,"
+"totduty integer not null,"+"subevalute varchar(20) not null,FOREIGN KEY(stuID) REFERENCES stuInfo(stuID),FOREIGN KEY(subID) REFERENCES subject(subID));");
db.execSQL("create table stuInfo2 (stuID varchar(20) primary key,"+"Nicheng varchar(20) not null,"
+"personInfo varchar(50) not null);");
db.execSQL("create table teaInfo2 (teaID varchar(20) primary key,"+"Nicheng varchar(20) not null,"
+"personInfo varchar(50) not null);");
db.insert("stuInfo",null, values);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("alter table person add account varchar(20)");
}
}
Service-Dataservice部署//
public class MyService extends Service{
public static SQLiteCreateHelper helper;//全局变量，如果不创建，会导致在访问数据库时，无法操作
IStudentImpl istu = new IStudentImpl();
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
helper=new SQLiteCreateHelper(MainActivity.context);
return istu;
}
@Override
public void onCreate() {
// TODO Auto-generated method stub
super.onCreate();
Log.d("Server-Service","onCreate");
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// TODO Auto-generated method stub
Log.d("Server-Service","onStartCommand");
return super.onStartCommand(intent, flags, startId);
}
@Override
public void onDestroy() {
// TODO Auto-generated method stub
Log.d("Server-Service","onDestroy");
super.onDestroy();
}
@Override
public boolean onUnbind(Intent intent) {
// TODO Auto-generated method stub
Log.d("Server-Service","onUnbind");
return super.onUnbind(intent);
}
}
AIDL 接口
package com.example.servicetest01;//包名一定要跟原本的包名一样，否则gen无法自动生成.Java文件
interface IStudent{
boolean selectID(String id);
String selectPass(String id);
}
IStudentImpl 具体实现接口类
public class IStudentImpl extends IStudent.Stub{
//private SQLiteCreateHelper helper;
private Context context;
//private Cursor cursor;
public IStudentImpl()
{
System.out.println("数据库连接成功");
//this.helper=MyService.helper;
this.context=MainActivity.context;
}
@Override
public boolean selectID(String id) throws RemoteException {
// TODO Auto-generated method stub
SQLiteDatabase db=MyService.helper.getWritableDatabase();
SQLiteCreateHelper.cursor=db.rawQuery("select stuID from stuInfo where stuID=?",new String[]{id});
boolean result=SQLiteCreateHelper.cursor.moveToNext();
SQLiteCreateHelper.cursor.close();
db.close();
return result;
}
@Override
public String selectPass(String id) throws RemoteException {
// TODO Auto-generated method stub
String pass="";
SQLiteDatabase db=MyService.helper.getWritableDatabase();
SQLiteCreateHelper.cursor=db.rawQuery("select stupassword from stuInfo where stuID=?", new String[]{id});
if(SQLiteCreateHelper.cursor==null)
{
Toast.makeText(context, "无数据", Toast.LENGTH_LONG).show();
}
else {
while(SQLiteCreateHelper.cursor.moveToNext())
{
pass = SQLiteCreateHelper.cursor.getString(SQLiteCreateHelper.cursor.getColumnIndex("stupassword"));
}
}
SQLiteCreateHelper.cursor.close();
db.close();
return pass;
}
}
！！！！！！！！！！！！！！！！最后注册清单一定要写！！！！！！！！！！！！！！！！
<service android:name=".MyService">
<intent-filter >
<action android:name="com.example.servicetest01.MyService"/>//设置action可以使其他app也能调用此Impl
</intent-filter>
</service>//服务端部署完成
//关于AIDL在下一篇详讲