手机安全卫士知识总结黑马程序员android

内容提供者 策略内容提供者中数据更改可被类似于JavaBean一样，外部程序不能直接本程序中的数据库，这里ContentProvider就 crud相应的4个方 用于对外提供CRUD操作 Url所代表数据的MIME返回的是单条记录：以 开头，如vnd.android.cursor.item/返回的是多条记录：以 开头，如vnd.android.cursor.dir/在文件的<application>节点下进行配置，<provider>中需要指定name、exported ：是Provider时的路径，要唯一 authorites：<provider>authorites URIUriMatherContentUris工具类：CRUDUriContentUrisUriID部分,2withAppendedId(uri,id)IDparseId(uri)ID示例代码（内容提供者类publicclassHeimaProviderextendsContentProviderprivatestaticfinalint= //匹配privatestaticfinalintSTUDENT=2; //匹配码privatestaticfinalint_ID=3; //匹配码privateMyHelperhelper;/**Uri匹配器privateUriMatcheruriMatcher=newUriMatcher(UriMatcher.NO_MATCH);publicbooleanonCreate(){helper=newMyHelper(getContext());//==添加uri匹配模式,设置匹配码（参数3）Uri uriMatcher.addURI("vider","#", //uriMatcher.addURI("vider","student",return}publicUriinsert(Uriuri,ContentValuesvalues){Databasedb=helper.getWritableDatabase();switch(uriMatcher.match(uri //匹配 longid=db.insert("","id",values);returnContentUris.withAppendedId(uri, //在原uri上拼上id，生成caselonginsert=db.insert("student","id",values);returnContentUris.withAppendedId(uri, //为路径上，加上不是合法的}}publicintdelete(Uriuri,Stringselection,String[]selectionArgs){Databasedb=helper.getWritableDatabase();switch(uriMatcher.match(uri //匹配caselongparseId //获取传过来的IDselection //设置查询条selectionArgsnewStringparseId //查询条件值

caseintdelete=db.delete("",selection,selectionArgs);return不是合法的}}

publicintupdate(Uriuri,ContentValuesvalues,Stringselection,String[]selectionArgs){Databasedb=helper.getWritableDatabase();switch(uriMatcher.match(uri))caselongparseId //获取传过来的IDselection //设置查询条selectionArgsnewStringparseId //查询条件值 intupdate=db.update("",values,selection,selectionArgs);return不是合法的}}publicCursorquery(Uriuri,String[]projection,Stringselection,String[]selectionArgs,StringsortOrder){Databasedb=switch(uriMatcher.match(uri))case//==根据ID查询==longparseId //获取传过来的IDselection //设置查询条selectionArgsnewStringparseId //查询条件值 Cursorcursor=db.query("",projection,selection,selectionArgs,null,

//==注意：此处的db与cursor不能关闭==return

不是合法的}}//返回传入URI的类型，可用于测试URIpublicStringgetType(Uriuri){switch(uriMatcher.match(uri)){case_ID: //表示单 记 //表单多 记return}}} .provider"1.2内容提供者通过Context获得ContentResolver内 publicclassHeimaProviderTestextendsAndroidTestCase/**测试添加数据publicvoidtestInsert()ContentResolverresolver=this.getContext().getContentResolver();Uriuri=Uri.parse(" ContentValuesvalues=newContentValues();values.put("name","小翼");values.put("balance13000);Uriinsertresolver.insert(uri //获取返回的uri}/**测试删除publicvoidtestRemove()ContentResolverresolverthis.getContext().getContentResolver();Uriuri=Uri.parse(" intcount=resolver.delete(uri,"id=?",newString[]{3+""});System.out.println("删除了"+count+"行");}/**测试更新publicvoidtestUpdate()ContentResolverresolver=this.getContext().getContentResolver();Uriuri=Uri.parse(" ContentValuesvalues=newContentValues();values.put("name","update");values.put("balance",56789);intupdateresolver.update(urivalues,"idnewString6System.out.println("更新了"+update+"行");}/**测试查询publicvoidtestQueryOne()ContentResolverresolver=this.getContext().getContentResolver();Uriuri= Cursorc=resolver.query(uri,newString[]{"name","balance"},"id=?",new{101+""},if(c.moveToNext()){System.out.println(""+c.getInt(1));}}/**测试查询全部publicvoidtestQueryAll()

ContentResolverresolver=this.getContext().getContentResolver();Uriuri= Cursorc=resolver.query(uri,newString[]{"id","name","balance"},null,null,while(c.moveToNext())System.out.println(c.getInt(0)+","+c.getString(1)+","+}}/**测试查询一条publicvoidtestQueryOneWithUriId()ContentResolverresolver=Uriuri= //查询ID为3的录Cursorc=resolver.query(uri,newString[]{"id","name","balance"},null,null,null);if(c.moveToNext()){System.out.println(c.getInt(0)+","+c.getString(1)+","+}}}

/**测试获取内容提供者的返回类型publicvoidtestGetType()ContentResolverresolver= }1.3内容提供者的数据变ContextgetContentResolver()ContentResolver调用其registerContentObserver()方法指定对某个UriContentObserver自定义ContentObserveronChange()方法获取数据示例代码（发通知部分publicintdelete(Uriuri,Stringselection,String[]selectionArgs){Databasedb=helper.getWritableDatabase();intdelete=db.delete("",selection,//==通过内容者对象ContentResolve发通知给所有的Observer==getContext().getContentResolver().notifyChange(uri,null);return}}//内容观察privatevoidinitRegisterContentObserver()Uriuri= 的//==第2个参数：true表示的uri的后代都可以 到==getContentResolver().registerContentObserver(uri,true,newContentObserver(newHandler())publicvoidonChange(booleanselfChange List ((BaseAdapter)}}内容提供者的简单示2.1Android系统提供了Provider 数据库在 定义一个Observer需限内容观察者一直在这个消息信箱，这样内容观察者收到这个消息后，就会响应；//publicclassMainActivityextendsActivity{protectedvoidonCreate(BundlesavedInstanceState){}//privatevoidinitSmsObserver()finalUriuri=Uri.parse("content://sms"); //内容提供者的URI地址,content://sms全部getContentResolver().registerContentObserver(uri,true,newContentObserver(newHandler()){publicvoidonChange(booleanselfChange)//通过内容提供者来获取信息,这里获取最后一Cursorc=getContentResolver().query(uri,newString[]{"address","date","type","body"},null,null,"_idDESCLIMIT1");if(c.moveToNext())Stringaddress=c.getS