魔乐科技安卓开发教程----李兴华----02ContentProvider

1.ContentProvider简介

客户端操作contentResolver和操作ContentProvider是一样的
Uri的辅助操作类ContentUris

2.ContentProvider数据库操作

项目类结构
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1、创建元数据MetaData

2、定义一个SQLiteOpenHelper类的子类，用于创建和删除member表

3、

先放弃一下下

3.利用ContentProvider访问联系人

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1、创建动态访问联系人权限（或许可以省略）
创建 PermisionUtils 类

public class PermisionUtils {private static final int REQUEST_READ_CONTACTS = 1;private static String[] PERMISSIONS_CONTACTS = {Manifest.permission.READ_CONTACTS,Manifest.permission.WRITE_CONTACTS};public static void verifyContactsPermissions(Activity activity) {//检查权限int permission = ActivityCompat.checkSelfPermission(activity,Manifest.permission.WRITE_CONTACTS);if (permission != PackageManager.PERMISSION_GRANTED) {//无权限ActivityCompat.requestPermissions(activity, PERMISSIONS_CONTACTS,REQUEST_READ_CONTACTS);//动态赋权}}}

2、创建listview布局页面contacts.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="horizontal"android:layout_width="match_parent"android:layout_height="wrap_content"><TextViewandroid:id="@+id/_id"android:layout_marginLeft="10dp"android:textSize="14sp"android:layout_width="30sp"android:layout_height="35dp"/><TextViewandroid:id="@+id/name"android:text="联系人"android:textSize="14sp"android:layout_width="wrap_content"android:layout_height="35dp"/></LinearLayout>

3、Manifest文件

<manifest xmlns:android="http://schemas.android.com/apk/res/android"package="com.fengray.myex004contactperson"><applicationandroid:allowBackup="true"android:icon="@mipmap/ic_launcher"android:label="@string/app_name"android:roundIcon="@mipmap/ic_launcher_round"android:supportsRtl="true"android:theme="@style/AppTheme"><activity android:name=".MainActivity"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity></application><uses-permission android:name="android.permission.READ_CONTACTS"/><uses-permission android:name="android.permission.WRITE_CONTACTS"/>
</manifest>

4、主布局页面

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical"android:layout_width="match_parent"android:layout_height="match_parent"><TextViewandroid:textSize="14sp"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="手机联系人列表" /><ListViewandroid:id="@+id/contactsList"android:layout_width="match_parent"android:layout_height="wrap_content"/></LinearLayout>

5、activity页面

public class MainActivity extends AppCompatActivity {private ListView contactsList=null;private List<Map<String,Object>> allContacts=null;private SimpleAdapter simpleadpter=null;private Cursor  result=null;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);//PermisionUtils.verifyContactsPermissions(this);contactsList=findViewById(R.id.contactsList);//查询result=getContentResolver().query(ContactsContract.Contacts.CONTENT_URI,null,null,null,null);//将结果集交给容器管理startManagingCursor(result);//实例化List集合allContacts=new ArrayList<Map<String, Object>>();//循环读取结果集中的数据并put到map中，最后添加到list表中for (result.moveToFirst();!result.isAfterLast();result.moveToNext()){Map<String,Object> map=new HashMap<String,Object>();//以上取出结果集中的每一个内容map.put("_id",result.getInt(result.getColumnIndex(ContactsContract.Contacts._ID)));map.put("name",result.getString(result.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME)));allContacts.add(map);}//创建adaptersimpleadpter=new SimpleAdapter(this,allContacts,R.layout.contacts,new String[]{"_id","name"},new int[]{R.id._id,R.id.name});contactsList.setAdapter(simpleadpter);//设置adpateregisterForContextMenu(this.contactsList);}//创建操作上下文菜单@Overridepublic void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {//super.onCreateContextMenu(menu, v, menuInfo);menu.setHeaderTitle("操作");menu.add(menu.NONE, Menu.FIRST+1,1,"查看信息");menu.add(menu.NONE, Menu.FIRST+2,1,"删除信息");}@Overridepublic boolean onContextItemSelected(@NonNull MenuItem item) {AdapterView.AdapterContextMenuInfo info= (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();int position=info.position;//取得上下文操作菜单的位置String contactsID=allContacts.get(position).get("_id").toString();switch (item.getItemId()){case Menu.FIRST+1:String phoneSelection= ContactsContract.CommonDataKinds.Phone.CONTACT_ID+"=?";String [] phoneSelectionArgs=new String[]{contactsID};Cursor cursor=getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,null,phoneSelection,phoneSelectionArgs,null);StringBuffer stringBuffer=new StringBuffer();stringBuffer.append("电话号码：");for (cursor.moveToFirst(); !cursor.isAfterLast();cursor.moveToNext()){stringBuffer.append(cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER)));}Toast.makeText(this, stringBuffer, Toast.LENGTH_SHORT).show();break;case Menu.FIRST+2:getContentResolver().delete(Uri.withAppendedPath(ContactsContract.Contacts.CONTENT_URI,contactsID),null,null);allContacts.remove(position);//输出集合数据项simpleadpter.notifyDataSetChanged();//通知改变Toast.makeText(this, "数据已删除", Toast.LENGTH_SHORT).show();break;}return super.onContextItemSelected(item);}
}

结果：
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4.利用ContentProvider访问通话记录

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1、创建动态访问联系人通话CALL_LOG权限（或许可以省略）
创建PermisionUtils 类
首次执行被询问

public class PermisionUtils {private static final int REQUEST_CALLLOG = 1;private static String[] PERMISSIONS_CALLLOG = {Manifest.permission.READ_CALL_LOG,Manifest.permission.WRITE_CALL_LOG};public static void verifyCallLogPermissions(Activity activity) {//检查权限int permission = ActivityCompat.checkSelfPermission(activity,Manifest.permission.WRITE_CALL_LOG);if (permission != PackageManager.PERMISSION_GRANTED) {//无权限ActivityCompat.requestPermissions(activity, PERMISSIONS_CALLLOG,REQUEST_CALLLOG);//动态赋权}}}

2、adapter布局文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="horizontal"android:layout_width="match_parent"android:layout_height="wrap_content"><TextViewandroid:id="@+id/_id"android:layout_marginLeft="10dp"android:textSize="14sp"android:layout_width="15sp"android:layout_height="35dp"/><TextViewandroid:id="@+id/name"android:text="联系人"android:textSize="14sp"android:layout_width="wrap_content"android:layout_height="35dp"/><TextViewandroid:id="@+id/number"android:text="电话号码"android:textSize="14sp"android:layout_marginLeft="10dp"android:layout_width="wrap_content"android:layout_height="35dp"/></LinearLayout>

3、主布局文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"><ListViewandroid:id="@+id/callist"android:layout_width="wrap_content"android:layout_height="wrap_content"/></LinearLayout>

4、Manifest文件

<manifest xmlns:android="http://schemas.android.com/apk/res/android"package="com.fengray.myex005tonghua"><uses-permission android:name="android.permission.READ_CALL_LOG" /><uses-permission android:name="android.permission.WRITE_CALL_LOG" /><applicationandroid:allowBackup="true"android:icon="@mipmap/ic_launcher"android:label="@string/app_name"android:roundIcon="@mipmap/ic_launcher_round"android:supportsRtl="true"android:theme="@style/AppTheme"><activity android:name=".MainActivity"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity></application></manifest>

5、主activity文件

public class MainActivity extends AppCompatActivity {private ListView callist;private Cursor result = null;//结果指针private List<Map<String, Object>> allCalls = null;private SimpleAdapter adapter = null;@RequiresApi(api = Build.VERSION_CODES.O)@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);PermisionUtils.verifyCallLogPermissions(this);callist = findViewById(R.id.callist);if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_CALL_LOG) != PackageManager.PERMISSION_GRANTED) {return;}result = getContentResolver().query(CallLog.Calls.CONTENT_URI, null, null, null,null);//查询通话记录startManagingCursor(result);//将结果集交给管理器执行//创建ListallCalls=new ArrayList<>();for (result.moveToFirst();!result.isAfterLast();result.moveToNext()){Map<String ,Object> contact=new HashMap<>();contact.put("_id",result.getInt(result.getColumnIndex(CallLog.Calls._ID)));String tempString=result.getString(result.getColumnIndex(CallLog.Calls.CACHED_NAME));//实操中没有取到这个值Log.d("jian", "onCreate: "+tempString);if (tempString==null || "".equals(tempString)){tempString="未知";}contact.put("name",tempString);contact.put("number",result.getInt(result.getColumnIndex(CallLog.Calls.NUMBER)));allCalls.add(contact);}adapter=new SimpleAdapter(this,allCalls,R.layout.contacts,new String[]{"_id","name","number"},new int[]{R.id._id,R.id.name,R.id.number});callist.setAdapter(adapter);}
}

结果：始终未能读取到name，不知道为什么
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4.SimpleCursorAdapter

创建PermisionUtils 类
首次执行被询问

public class PermisionUtils {private static final int REQUEST_CALLLOG = 1;private static String[] PERMISSIONS_CALLLOG = {Manifest.permission.READ_CALL_LOG,Manifest.permission.WRITE_CALL_LOG};public static void verifyCallLogPermissions(Activity activity) {//检查权限int permission = ActivityCompat.checkSelfPermission(activity,Manifest.permission.WRITE_CALL_LOG);if (permission != PackageManager.PERMISSION_GRANTED) {//无权限ActivityCompat.requestPermissions(activity, PERMISSIONS_CALLLOG,REQUEST_CALLLOG);//动态赋权}}}