Android基礎-ContentProvider多媒體課件

Android四大組件之ContentProviderAndroid基礎-ContentProvider一、什么是ContentProviderContentProvider用來存儲和檢索數據ContentProvider是應用之間互相訪問數據的唯一方法Android自身提供了一些常用的Provideraudio、video、image、contacts等如果你想使你的數據能夠共享，要么建立一個你自己的ContentProvider；要么往已存在的ContentProvider中寫數據Android基礎-ContentProvider如何訪問ContentProvider借助工具類ContentResolver獲得ContentResolver由activity或context的方法：getContentResolver()使用ContentResolver的方法訪問數據庫查找：query插入：insert更新：update刪除：deleteAndroid基礎-ContentProviderContentProvider如何存儲數據每一個ContentProvider都有一個Uri來標識它本身vider.Contacts.Phones.CONTENT_URIContentProvider存儲數據的形式：Android基礎-ContentProviderContentProvider的查找finalCursorContentResolver.query(Uriuri,String[]projection,Stringselection,String[]selectionArgs,StringsortOrder)使用者自行管理Cursor的生命周期finalCursorActivity.managedQuery(Uriuri,String[]projection,Stringselection,String[]selectionArgs,StringsortOrder)由所在的Activity來管理Cursor的生命周期Android基礎-ContentProviderContentProvider的查找String[]projection=newString[]{People._ID,People._COUNT,,People.NUMBER};Uricontacts=People.CONTENT_URI;CursormanagedCursor=managedQuery(contacts,projection,//Whichcolumnstoreturnnull,//Whichrowstoreturn(allrows)null,//Selectionarguments(none)//Puttheresultsinascendingorderbyname+"ASC");Android基礎-ContentProviderContentProvider的查找privatevoidgetColumnData(Cursorcur){if(cur.moveToFirst()){Stringname,phoneNumber;intnameColumn=cur.getColumnInde);intphoneColumn=cur.getColumnIndex(People.NUMBER);StringimagePath;do{name=cur.getString(nameColumn);phoneNumber=cur.getString(phoneColumn);}while(cur.moveToNext());}}Android基礎-ContentProvider修改ContentProvider的數據增加一條新記錄：insert給一條已存在的記錄增加新信息：insert更新記錄：update刪除記錄：delete借助：ContentValues、ContentResolverAndroid基礎-ContentProvider增加一條新記錄ContentValuesvalues=newContentValues();//AddAbrahamLincolntocontactsandmakehimafavorite.values.pu,"AbrahamLincoln");//1=thenewcontactisaddedtofavorites//0=thenewcontactisnotaddedtofavoritesvalues.put(People.STARRED,1);Uriuri=getContentResolver().insert(People.CONTENT_URI,values);Android基礎-ContentProvider已有記錄增加新信息UriphoneUri=null;phoneUri=Uri.withAppendedPath(uri,People.Phones.CONTENT_DIRECTORY);values.clear();values.put(People.Phones.TYPE,People.Phones.TYPE_MOBILE);values.put(People.Phones.NUMBER,"1233214567");getContentResolver().insert(phoneUri,values);Android基礎-ContentProvider更新和刪除更新：ContentResolver.update()刪除：ContentResolver.delete()Android基礎-ContentProvider如何創(chuàng)建ContentProvider？通過Sqlite的方式建立ContentProvider繼承ContentProvider類實現SQLiteOpenHelper實現增刪改查等接口queryinsertupdatedeletegetTypeonCreateAndroid基礎-ContentProvider如何創(chuàng)建ContentProvider？在manifest中聲明ContentProvider<providerandroid:name="com.example.autos.AutoInfoProvider"android:authori