本节引言:
1.ContentProvider概念讲解:
2.使用系统提供的ContentProvider
1)简单的读取收件箱信息:
核心代码:
private void getMsgs(){ Uri uri = Uri.parse("content://sms/"); ContentResolver resolver = getContentResolver(); //获取的是哪些列的信息 Cursor cursor = resolver.query(uri, new String[]{"address","date","type","body"}, null, null, null); while(cursor.moveToNext()) { String address = cursor.getString(0); String date = cursor.getString(1); String type = cursor.getString(2); String body = cursor.getString(3); System.out.println("地址:" + address); System.out.println("时间:" + date); System.out.println("类型:" + type); System.out.println("内容:" + body); System.out.println("======================"); } cursor.close(); }
别忘了,往AndroidManifest.xml加入读取收件箱的权限:
<uses-permission android:name="android.permission.READ_SMS"/>
运行结果:
部分运行结果如下:
2)简单的往收件箱里插入一条信息
核心代码:
private void insertMsg() { ContentResolver resolver = getContentResolver(); Uri uri = Uri.parse("content://sms/"); ContentValues conValues = new ContentValues(); conValues.put("address", "123456789"); conValues.put("type", 1); conValues.put("date", System.currentTimeMillis()); conValues.put("body", "no zuo no die why you try!"); resolver.insert(uri, conValues); Log.e("HeHe", "短信插入完毕~"); }
运行结果:
注意事项:
上述代码在4.4以下都可以实现写入短信的功能,而5.0上就无法写入,原因是: 从5.0开始,默认短信应用外的软件不能以写入短信数据库的形式发短信!
3)简单的读取手机联系人
核心代码:
private void getContacts(){ //①查询raw_contacts表获得联系人的id ContentResolver resolver = getContentResolver(); Uri uri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI; //查询联系人数据 cursor = resolver.query(uri, null, null, null, null); while(cursor.moveToNext()) { //获取联系人姓名,手机号码 String cName = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME)); String cNum = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER)); System.out.println("姓名:" + cName); System.out.println("号码:" + cNum); System.out.println("======================"); } cursor.close(); }
别忘了加读联系人的权限:
<uses-permission android:name="android.permission.READ_CONTACTS"/>
运行结果:
部分运行结果如下:
4)查询指定电话的联系人信息
核心代码:
private void queryContact(String number){ Uri uri = Uri.parse("content://com.android.contacts/data/phones/filter/" + number); ContentResolver resolver = getContentResolver(); Cursor cursor = resolver.query(uri, new String[]{"display_name"}, null, null, null); if (cursor.moveToFirst()) { String name = cursor.getString(0); System.out.println(number + "对应的联系人名称:" + name); } cursor.close(); }
运行结果:
5)添加一个新的联系人
核心代码:
private void AddContact() throws RemoteException, OperationApplicationException { //使用事务添加联系人 Uri uri = Uri.parse("content://com.android.contacts/raw_contacts"); Uri dataUri = Uri.parse("content://com.android.contacts/data"); ContentResolver resolver = getContentResolver(); ArrayList<ContentProviderOperation> operations = new ArrayList<ContentProviderOperation>(); ContentProviderOperation op1 = ContentProviderOperation.newInsert(uri) .withValue("account_name", null) .build(); operations.add(op1); //依次是姓名,号码,邮编 ContentProviderOperation op2 = ContentProviderOperation.newInsert(dataUri) .withValueBackReference("raw_contact_id", 0) .withValue("mimetype", "vnd.android.cursor.item/name") .withValue("data2", "Coder-pig") .build(); operations.add(op2); ContentProviderOperation op3 = ContentProviderOperation.newInsert(dataUri) .withValueBackReference("raw_contact_id", 0) .withValue("mimetype", "vnd.android.cursor.item/phone_v2") .withValue("data1", "13798988888") .withValue("data2", "2") .build(); operations.add(op3); ContentProviderOperation op4 = ContentProviderOperation.newInsert(dataUri) .withValueBackReference("raw_contact_id", 0) .withValue("mimetype", "vnd.android.cursor.item/email_v2") .withValue("data1", "779878443@qq.com") .withValue("data2", "2") .build(); operations.add(op4); //将上述内容添加到手机联系人中~ resolver.applyBatch("com.android.contacts", operations); Toast.makeText(getApplicationContext(), "添加成功", Toast.LENGTH_SHORT).show(); }
运行结果:
别忘了权限:
<uses-permission android:name="android.permission.WRITE_CONTACTS"/> <uses-permission android:name="android.permission.WRITE_PROFILE"/>
3.自定义ContentProvider
接下来我们就来一步步实现:
在开始之前我们先要创建一个数据库创建类(数据库内容后面会讲~):
DBOpenHelper.java
public class DBOpenHelper extends SQLiteOpenHelper { final String CREATE_SQL = "CREATE TABLE test(_id INTEGER PRIMARY KEY AUTOINCREMENT,name)"; public DBOpenHelper(Context context, String name, CursorFactory factory, int version) { super(context, name, null, 1); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(CREATE_SQL); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // TODO Auto-generated method stub } }
Step 1:自定义ContentProvider类,实现onCreate(),getType(),根据需求重写对应的增删改查方法:
NameContentProvider.java
public class NameContentProvider extends ContentProvider { //初始化一些常量 private static UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH); private DBOpenHelper dbOpenHelper; //为了方便直接使用UriMatcher,这里addURI,下面再调用Matcher进行匹配 static{ matcher.addURI("com.jay.example.providers.myprovider", "test", 1); } @Override public boolean onCreate() { dbOpenHelper = new DBOpenHelper(this.getContext(), "test.db", null, 1); return true; } @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { return null; } @Override public String getType(Uri uri) { return null; } @Override public Uri insert(Uri uri, ContentValues values) { switch(matcher.match(uri)) { //把数据库打开放到里面是想证明uri匹配完成 case 1: SQLiteDatabase db = dbOpenHelper.getReadableDatabase(); long rowId = db.insert("test", null, values); if(rowId > 0) { //在前面已有的Uri后面追加ID Uri nameUri = ContentUris.withAppendedId(uri, rowId); //通知数据已经发生改变 getContext().getContentResolver().notifyChange(nameUri, null); return nameUri; } } return null; } @Override public int delete(Uri uri, String selection, String[] selectionArgs) { return 0; } @Override public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { return 0; } }
Step 2:AndroidManifest.xml中为ContentProvider进行注册:
<!--属性依次为:全限定类名,用于匹配的URI,是否共享数据 --> <provider android:name="com.jay.example.bean.NameContentProvider" android:authorities="com.jay.example.providers.myprovider" android:exported="true" />
好的,作为ContentProvider的部分就完成了!
接下来,创建一个新的项目,我们来实现ContentResolver的部分,我们直接通过按钮点击插入一条数据:
MainActivity.java
public class MainActivity extends Activity { private Button btninsert; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); btninsert = (Button) findViewById(R.id.btninsert); //读取contentprovider 数据 final ContentResolver resolver = this.getContentResolver(); btninsert.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { ContentValues values = new ContentValues(); values.put("name", "测试"); Uri uri = Uri.parse("content://com.jay.example.providers.myprovider/test"); resolver.insert(uri, values); Toast.makeText(getApplicationContext(), "数据插入成功", Toast.LENGTH_SHORT).show(); } }); } }
如何使用? 好吧,代码还是蛮简单的,先运行作为ContentProvider的项目,接着再运行ContentResolver的项目, 点击按钮插入一条数据,然后打开file exploer将ContentProvider的db数据库取出,用图形查看工具 查看即可发现插入数据,时间关系,就不演示结果了~
4.通过ContentObserver监听ContentProvider的数据变化
使用指南: