《Android基础ContentProvider.PPT》由会员分享，可在线阅读，更多相关《Android基础ContentProvider.PPT（14页珍藏版）》请在金锄头文库上搜索。
1、Android四大组件之ContentProvider1.一、什么是一、什么是ContentProviderContentProvider用来存储和检索数据ContentProvider是应用之间互相访问数据的唯一方法Android自身提供了一些常用的Provideraudio、video、image、contacts等如果你想使你的数据能够共享，要么建立一个你自己的ContentProvider；要么往已存在的ContentProvider中写数据2.如何访问如何访问ContentProvider借助工具类ContentResolver获得ContentResolver由activity或c
2、ontext的方法：getContentResolver()使用ContentResolver的方法访问数据库查找：query插入：insert更新：update删除：delete3.Content Provider如何存储数据如何存储数据每一个Content Provider都有一个Uri来标识它本身android.provider.Contacts.Phones.CONTENT_URIContent Provider存储数据的形式：4.Content Provider的查找的查找final Cursor ContentResolver.query(Uri uri, String proje
3、ction, String selection, String selectionArgs, String sortOrder)使用者自行管理Cursor的生命周期final Cursor Activity.managedQuery(Uri uri, String projection, String selection, String selectionArgs, String sortOrder)由所在的Activity来管理Cursor的生命周期5.Content Provider的查找的查找String projection = new String People._ID, Peopl
4、e._COUNT, People.NAME, People.NUMBER ;Uri contacts = People.CONTENT_URI;Cursor managedCursor = managedQuery(contacts, projection, / Which columns to return null, / Which rows to return (all rows) null, / Selection arguments (none) / Put the results in ascending order by name People.NAME + ASC);6.Con
5、tent Provider的查找的查找private void getColumnData(Cursor cur) if (cur.moveToFirst() String name, phoneNumber; int nameColumn = cur.getColumnIndex(People.NAME); int phoneColumn = cur.getColumnIndex(People.NUMBER); String imagePath; do name = cur.getString(nameColumn); phoneNumber = cur.getString(phoneCol
6、umn); while (cur.moveToNext(); 7.修改修改Content Provider的数据的数据增加一条新记录：insert给一条已存在的记录增加新信息：insert更新记录：update删除记录：delete借助：ContentValues、ContentResolver8.增加一条新记录增加一条新记录ContentValues values = new ContentValues();/ Add Abraham Lincoln to contacts and make him a favorite.values.put(People.NAME, Abraham Lin
7、coln);/ 1 = the new contact is added to favorites/ 0 = the new contact is not added to favoritesvalues.put(People.STARRED, 1);Uri uri = getContentResolver().insert(People.CONTENT_URI, values);9.已有记录增加新信息已有记录增加新信息Uri phoneUri = null;phoneUri = Uri.withAppendedPath(uri, People.Phones.CONTENT_DIRECTORY
8、);values.clear();values.put(People.Phones.TYPE, People.Phones.TYPE_MOBILE);values.put(People.Phones.NUMBER, 1233214567);getContentResolver().insert(phoneUri, values);10.更新和删除更新和删除更新：ContentResolver.update()删除：ContentResolver.delete()11.如何创建如何创建Content Provider？通过Sqlite的方式建立ContentProvider继承ContentProvider类实现SQLiteOpenHelper实现增删改查等接口queryinsertupdatedeletegetTypeonCreate12.如何创建如何创建Content Provider？在manifest中声明ContentProvider13.The End!14.
