Android的ContentProvider

一、概述

ContentProvider(数据提供者)是应用程序之间共享数据的一种接口机制，是一种更为高级的数据共享方法。

ContentProvider可以指定需要共享的数据，而其他应用程序则可以在不知道数据来源、路径的情况下，对共享数据进行增删改查等操作。
在Android系统中，许多Android系统内置的数据也是通过ContentProvider提供给用户使用，例如通讯录、音视频文件和图像文件等

二、使用关系

三、类关系

CPP与CPN是一对Binder通信的C/S两端;
ACR(ApplicationContentResolver)继承于ContentResolver, 位于ContextImpl的内部类. ACR的实现往往是通过调用其成员变量mMainThread(数据类型为ActivityThread)来完成;

四、ContentProvider中的URI

因为Uri代表了要操作的数据，所以我们经常需要解析Uri，并从Uri中获取数据。Android系统提供了两个用于操作Uri的工具类，分别为UriMatcher和ContentUris 。

4.1. UriMatcher

UriMatcher 类主要用于匹配Uri.

使用方法

1.初始化

mUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);

2.注册需要的Uri

sAuthority = getContext().getPackageName() + "." + AoaoyiContentProvider.class.getSimpleName();
mUriMatcher.addURI(sAuthority, DBData.TABLE_USER, 1);
mUriMatcher.addURI(sAuthority, DBData.TABLE_USER + "/raw", 2);
mUriMatcher.addURI(sAuthority, DBData.TABLE_SP, 3);

3.与已经注册的Uri进行匹配(match方法匹配后会返回一个匹配码Code，即在使用注册方法addURI时传入的第三个参数。)

switch (mUriMatcher.match(uri)) {
    case 1:
        cursor = db.query(DBData.TABLE_USER, projection, selection, selectionArgs, null, null, sortOrder, null);
        break;
    case 2:
        cursor = db.rawQuery(selection, selectionArgs);
        break;
    case 3:
        cursor = db.query(DBData.TABLE_SP, projection, selection, selectionArgs, null, null, sortOrder, null);
        break;
}

4.2. ContentUris

ContentUris 类用于获取Uri路径后面的ID部分

使用方法：

1. 为路径加上ID: withAppendedId(uri, id)

ContentUris.withAppendedId(uri, id);ContentUris.parseId(uri)

1. 从路径中获取ID: parseId(uri)

ContentUris.parseId(uri)

五、具体实现

我下面实现一个APP内跨进程访问数据的例子，目的是利用ContentProvider确保跨进程操作数据安全：

1. 需要在AndroidManifest.xml使用<provider>对该ContentProvider进行配置，为了能让其他应用找到该ContentProvider ，ContentProvider采用了authorities（主机名/域名）对它进行唯一标识，你可以把ContentProvider看作是一个网站（想想，网站也是提供数据者），authorities 就是他的域名：

<provider
   android:name="com.aoaoyi.provider.AoaoyiContentProvider"
   android:authorities="{AppPackageName}.AoaoyiContentProvider"
   android:enabled="true"
   android:exported="true" />

2.创建AoaoyiContentProvider.java

public class AoaoyiContentProvider extends ContentProvider{
    private static final String TAG = AoaoyiContentProvider.class.getSimpleName();

    private DBHelper mDBHelper;
    private UriMatcher mUriMatcher;
    private ContentResolver mResolver;

    public static String sAuthority;

    @Override
    public boolean onCreate() {
        mDBHelper = DBHelper.getInstance(getContext());
        mResolver = getContext().getContentResolver();
        sAuthority = getContext().getPackageName() + "." + AoaoyiContentProvider.class.getSimpleName();
        mUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
        mUriMatcher.addURI(sAuthority, DBData.TABLE_USER, 1);
        mUriMatcher.addURI(sAuthority, DBData.TABLE_USER + "/raw", 2);
        mUriMatcher.addURI(sAuthority, DBData.TABLE_SP, 3);
        return true;
    }

    @Nullable
    @Override
    public Cursor query(@NonNull Uri uri, @Nullable String[] projection, @Nullable String selection, @Nullable String[] selectionArgs, @Nullable String sortOrder) {
        Cursor cursor = null;
        try {
            SQLiteDatabase db = mDBHelper.getWritableDatabase();

            switch (mUriMatcher.match(uri)) {
                case 1:
                    cursor = db.query(DBData.TABLE_USER, projection, selection, selectionArgs, null, null, sortOrder, null);
                    break;
                case 2:
                    cursor = db.rawQuery(selection, selectionArgs);
                    break;
                case 3:
                    cursor = db.query(DBData.TABLE_SP, projection, selection, selectionArgs, null, null, sortOrder, null);
                    break;
            }
        }
        catch (Exception e) {
            Log.i(TAG, "query:Exception:" + e.toString());
        } catch (Error e) {
            Log.i(TAG, "query:Error:" + e.toString());
        }

        return cursor;
    }


    @Nullable
    @Override
    public String getType(@NonNull Uri uri) {
        String result = null;
        switch (mUriMatcher.match(uri)) {
            case 1:
            case 2:
                result = "vnd.android.cursor.dir/vnd." + AoaoyiContentProvider.class.getName() + "." + DBData.TABLE_USER;
                break;
            case 3:
                result = "vnd.android.cursor.item/vnd." + AoaoyiContentProvider.class.getName() + "." + DBData.TABLE_SP;
                break;
        }

        return result;
    }

    @Nullable
    @Override
    public Uri insert(@NonNull Uri uri, @Nullable ContentValues values) {
        Uri result = null;
        long id = -1;
        try {
            SQLiteDatabase db = mDBHelper.getWritableDatabase();
            switch (mUriMatcher.match(uri)) {
                case 1:
                case 2:
                    id = db.insert(DBData.TABLE_USER, null, values);
                    break;
                case 3:
                    id = db.insert(DBData.TABLE_SP, null, values);
                    break;
            }
            if(id < 0) {
                result = uri;
            } else {
                result = ContentUris.withAppendedId(uri, id);
                mResolver.notifyChange(result, null);
            }
            Log.d(TAG, "insert:" + id);
        } catch (Exception e) {
            Log.i(TAG, "insert:Exception:" + e.toString());
        } catch (Error e) {
            Log.i(TAG, "insert:Error:" + e.toString());
        }

        return result;
    }

    @Override
    public int delete(@NonNull Uri uri, @Nullable String selection, @Nullable String[] selectionArgs) {
        int result = 0;
        try {
            SQLiteDatabase db = mDBHelper.getWritableDatabase();
            switch (mUriMatcher.match(uri)) {
                case 1:
                    result = db.delete(DBData.TABLE_USER, selection, selectionArgs);
                    break;
                case 2:
                    db.execSQL(selection);
                    break;
                case 3:
                    result = db.delete(DBData.TABLE_SP, selection, selectionArgs);
                    break;
            }
            Log.d(TAG, "delete:" + result);
        } catch (Exception e) {
            result = 0;
            Log.i(TAG, "delete:Exception:" + e.toString());
        } catch (Error e) {
            result = 0;
            Log.i(TAG, "delete:Error:" + e.toString());
        }

        return result;
    }

    @Override
    public int update(@NonNull Uri uri, @Nullable ContentValues values, @Nullable String selection, @Nullable String[] selectionArgs) {
        int result = 0;
        try {
            SQLiteDatabase db = mDBHelper.getWritableDatabase();
            switch (mUriMatcher.match(uri)) {
                case 1:
                    result = db.update(DBData.TABLE_USER, values, selection, selectionArgs);
                    break;
                case 2:
                    db.execSQL(selection);
                    break;
                case 3:
                    result = db.update(DBData.TABLE_SP, values, selection, selectionArgs);
                    break;
            }

            if(result > 0)
                mResolver.notifyChange(uri, null);
            Log.d(TAG, "update:" + result);
        } catch (Exception e) {
            result = 0;
            Log.i(TAG, "update:Exception:" + e.toString());
        } catch (Error e) {
            result = 0;
            Log.i(TAG, "update:Error:" + e.toString());
        }

        return result;
    }
}

3.其中用到的DBData.java

public class DBData {
    /* 数据库 */
    /** SDK 本地数据库名 */
    public static final String DB_NAME = "aoaoyi_db";
    /** SDK 本地数据库的版本号,用于数据升级 */
    public static final int DB_VERSION = 1;

    /* ====== SP BEGIN =======*/
    /** SharePreference 表名*/
    public static final String TABLE_SP = "sp";
    /** 自增字段 */
    public static final String SP_AUTO_ID = "_id";
    /** Key */
    public static final String SP_KEY = "key";
    /** Value */
    public static final String SP_VALUE = "value";
    /** CreateTime */
    public static final String SP_CREATE_TIME = "create_time";

    /** 创建SP表 */
    public static final String SQL_CREATE_SP = "CREATE TABLE IF NOT EXISTS "
            + TABLE_SP + "("
            + SP_AUTO_ID + " INTEGER PRIMARY KEY AUTOINCREMENT,"
            + SP_KEY + " VARCHAR,"
            + SP_VALUE + " VARCHAR,"
            + SP_CREATE_TIME + " INTEGER DEFAULT (strftime('%s','now')*1000))";

    /** 添加表索引 */
    public static final String SQL_CREATE_SP_INDEX = "CREATE INDEX IF NOT EXISTS "
            + " sp_key_index "
            + " on "
            + TABLE_SP
            + " ( "
            + SP_KEY
            + " ) ";

    /* ====== SP END =======*/

    /* ====== USER BEGIN =======*/
    public static final String TABLE_USER = "user";
    public static final String USER_AUTO_ID = "_id";
    public static final String USER_ID = "id";
    public static final String USER_NICK_NAME = "nick_name";
    public static final String USER_PROFILE_PIC_URL = "profile_pic_url";
    public static final String USER_PHONE_NUM = "phone_num";
    public static final String USER_EMAIL = "email";
    public static final String USER_ADDRESS = "address";
    public static final String USER_CREATE_TIME = "user_create_time";

    /** create table */
    public static final String SQL_CREATE_USER = "CREATE TABLE IF NOT EXISTS "
            + TABLE_USER + "("
            + USER_AUTO_ID + " INTEGER PRIMARY KEY AUTOINCREMENT,"
            + USER_ID + " INTEGER,"
            + USER_NICK_NAME + " VARCHAR,"
            + USER_PROFILE_PIC_URL + " VARCHAR,"
            + USER_PHONE_NUM + " VARCHAR,"
            + USER_EMAIL + " VARCHAR,"
            + USER_ADDRESS + " TEXT,"
            + USER_CREATE_TIME + " INTEGER DEFAULT (strftime('%s','now')*1000))";

    /** 添加表索引 */
    public static final String SQL_CREATE_USER_INDEX = "CREATE INDEX IF NOT EXISTS "
            + " user_phone_index "
            + " on "
            + TABLE_USER
            + " ( "
            + USER_ID
            + ", "
            + USER_PHONE_NUM
            + " ) ";

    /* ====== USER END =======*/

}

4.其中用到的DBHelper.java

public class DBHelper extends SQLiteOpenHelper {
    /** TAG */
    private static final String TAG = DBHelper.class.getSimpleName();
    /** DBHelper */
    private volatile static DBHelper mDBHelper = null;

    /**
     * DBHelper 单例模式调用
     *
     * @param pContext Context
     *
     * @return SQLiteOpenHelper
     */
    public static DBHelper getInstance(Context pContext) {
        if (mDBHelper == null) {
            synchronized(DBHelper.class){
                if (mDBHelper == null) {
                    mDBHelper = new DBHelper(pContext.getApplicationContext());
                }
            }
        }
        return mDBHelper;
    }


    private DBHelper(Context pContext) {
        super(pContext, DBData.DB_NAME, null, DBData.DB_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase pDB) {
        //User
        pDB.execSQL(DBData.SQL_CREATE_USER);
        pDB.execSQL(DBData.SQL_CREATE_USER_INDEX);
        //SP
        pDB.execSQL(DBData.SQL_CREATE_SP);
        pDB.execSQL(DBData.SQL_CREATE_SP_INDEX);
    }

    @Override
    public void onUpgrade(SQLiteDatabase pDB, int pOldVersion, int pNewVersion) {
        for (int i = pOldVersion; i < pNewVersion; i++) {
            List<String> _UpgradeSQLList = getUpgradeSQL(i + 1);
            for (String _UpgradeSQL : _UpgradeSQLList) {
                try {
                    pDB.execSQL(_UpgradeSQL);
                } catch (Exception e) {
                    Log.e(getClass().getSimpleName(), "catch SQLException in onUpgrade() method", e);
                    e.printStackTrace();
                }
            }
        }
    }
    /**
     * 各个版本更新数据的SQL语句
     *
     * @param pVersion 版本号
     *
     * @return 各个版本需要更新的SQL语句的集合
     */
    private List<String> getUpgradeSQL(int pVersion) {
        //数据库所做的升级SQL语句
        List<String> _UpgradeSQLList = new ArrayList<>();
        switch (pVersion) {
            case 2:

                break;
            case 3:
                break;
        }
        return _UpgradeSQLList;
    }
}

5.其中用到的SPDao.java

public class SPDao {
    /** TAG */
    private static final String TAG = SPDao.class.getSimpleName();
    /** */
    private final byte[] sLock = new byte[0];
    private Context mContext;
    /** Authority */
    private static String mAuthority;
    /** 访问该ContentProvider的URI */
    private static Uri mUri;

    public SPDao(Context pContext){
        mContext = pContext.getApplicationContext();
        mAuthority = pContext.getPackageName() + "." + AoaoyiContentProvider.class.getSimpleName();
        mUri = Uri.parse("content://" + mAuthority + "/" + DBData.TABLE_SP);
    }

    /**
     * 插入Key和Value(存在进行更新，不存在进行插入)
     *
     * @param pKey key
     * @param pValue value
     * @return
     */
    public long insertKeyValue(final String pKey, final String pValue) {
        synchronized (sLock) {
            int result;
            try {
                if(!TextUtils.isEmpty(pKey) && !TextUtils.isEmpty(pValue)){
                    ContentValues cv = new ContentValues();
                    if (!isExistKey(pKey)){
                        //不存在插入
                        cv.put(DBData.SP_KEY, pKey);
                        cv.put(DBData.SP_VALUE, pValue);
                        Uri uri = mContext.getContentResolver().insert(mUri, cv);
                        if(ContentUris.parseId(uri) > 0){
                            Log.d(TAG, "Key:" + pKey + " value set to :" + pValue);
                            result = 1;
                        }else {
                            result = 0;
                            Log.d(TAG, "Key:" + pKey + " value set fail ");
                        }
                    }else {
                        //存在进行更新
                        cv.put(DBData.SP_VALUE, pValue);
                        String whereClause = DBData.SP_KEY + " = ? ";
                        String[] whereArgs = new String[] { pKey };
                        result = mContext.getContentResolver().update(mUri, cv, whereClause, whereArgs);
                        if (result > 0){
                            Log.d(TAG, "Key:" + pKey + " value update to :" + pValue);
                        }else {
                            Log.d(TAG, "Key:" + pKey + " value update fail ");
                        }
                    }
                }else {
                    result = 0;
                    Log.d(TAG, "Key or value is null ");
                }
            } catch (Exception e) {
                result = 0;
                Log.i(TAG, "insert:Exception:" + e.toString());
            } catch (Error e) {
                result = 0;
                Log.i(TAG, "insert:Error:" + e.toString());
            }
            return result;
        }
    }

    /**
     * 移除KeyValue
     *
     * @param pKey
     * @return 受影响的条数
     */
    public long removeKeyValue(final String pKey){
        synchronized(sLock) {
            long result;
            try {
                String whereClause = DBData.SP_KEY + " = ? ";
                String[] whereArgs = new String[] { pKey };
                result = mContext.getContentResolver().delete(mUri, whereClause, whereArgs);
                if (result > 0){
                    Log.d(TAG, "delete key:" + pKey + " success ");
                }else {
                    Log.d(TAG, "delete key:" + pKey + " fail ");
                }
            } catch (Exception e) {
                result = 0;
                Log.i(TAG, "remove:Exception:" + e.toString());
            } catch (Error e) {
                result = 0;
                Log.i(TAG, "remove:Error:" + e.toString());
            }
            return result;
        }
    }

    /**
     * 获取Value
     *
     * @param pKey Key
     * @return
     */
    public String getValueByKey(final String pKey){
        synchronized (sLock) {
            String value = "";
            try {
                String selection =  DBData.SP_KEY + " = ? ";
                String[] whereArgs = new String[] { pKey };
                String orderBy =  DBData.SP_AUTO_ID + " DESC ";
                Cursor cursor = mContext.getContentResolver().query(mUri, null, selection, whereArgs, orderBy);
                if (cursor != null && cursor.getCount() > 0) {
                    if (cursor.moveToFirst()){
                        value = cursor.getString(cursor.getColumnIndex(DBData.SP_VALUE));
                        Log.d(TAG, "Key:" + pKey + " value:" + value);
                    }
                }
                cursor.close();
            } catch (Exception e) {
                Log.i(TAG, "query:Exception:" + e.toString());
            } catch (Error e) {
                Log.i(TAG, "query:Error:" + e.toString());
            }
            return value;
        }
    }

    /**
     * 是否存在Key
     *
     * @param pKey key
     * @return true:存在;false:不存在;
     */
    private boolean isExistKey(final String pKey){
        synchronized (sLock) {
            Boolean result;
            try {
                String selection =  DBData.SP_KEY + " = ? ";
                String[] whereArgs = new String[] { pKey };
                Cursor cursor = mContext.getContentResolver().query(mUri, null, selection, whereArgs, null);
                result = cursor.getCount() > 0 ? true : false;
                cursor.close();
            } catch (Exception e) {
                result = false;
                Log.i(TAG, "exist:Exception:" + e.toString());
            } catch (Error e) {
                result = false;
                Log.i(TAG, "exist:Error:" + e.toString());
            }
            return result;
        }
    }
}

6.其中用到的UserInfoDao.java

public class UserInfoDao {
    private static final String TAG = UserInfoDao.class.getSimpleName();
    private final byte[] sLock = new byte[0];
    private Context mContext;
    /** Authority */
    private static String mAuthority;
    /** Uri */
    private static Uri mUri;
    /** Raw Uri */
    private static Uri mRawUri;

    public UserInfoDao(Context pContext){
        mContext = pContext.getApplicationContext();
        mAuthority = pContext.getPackageName() + "." + AoaoyiContentProvider.class.getSimpleName();
        mUri = Uri.parse("content://" + mAuthority + "/" + DBData.TABLE_USER);
        mRawUri = Uri.parse("content://" + mAuthority + "/" + DBData.TABLE_USER + "/raw");
    }

    public long insertList(List<UserInfo> userInfoList){
        synchronized (sLock) {
            int insertResult = 0;
            if (userInfoList == null){
                return insertResult;
            }
            ContentValues cv = new ContentValues();
            try{
                for (UserInfo userInfo : userInfoList){
                    if(isExist(userInfo.getUserId())){
                        //存在更新
                        cv = toContentValues(cv, userInfo);
                        String contentValues = DBData.USER_ID + " = ? ";
                        String[] whereArgs = new String[] { String.valueOf(userInfo.getUserId()) };
                        insertResult = mContext.getContentResolver().update(mUri, cv, contentValues, whereArgs);
                    }else {
                        //不存在,进行插入
                        cv = toContentValues(cv, userInfo);
                        Uri uri = mContext.getContentResolver().insert(mUri, cv);
                        if(ContentUris.parseId(uri) > 0){
                            insertResult ++;
                            Log.i(TAG, "UserId::" + userInfo.getUserId());
                        }
                    }
                }
            } catch (Exception e){
                Log.i(TAG, "insert:Exception:" + e.toString());
            } catch (Error e) {
                Log.i(TAG, "insert:Error:" + e.toString());
            }
            return insertResult;
        }
    }

    public long updateUserInfo(final UserInfo pUserInfo){
        synchronized(sLock) {
            long updateResult = 0;
            if (pUserInfo != null){
                try{
                    ContentValues cv = new ContentValues();
                    if (isExist(pUserInfo.getUserId())){
                        //存在
                        cv = toContentValues(cv, pUserInfo);
                        String contentValues = DBData.USER_ID + " = ? ";
                        String[] whereArgs = new String[] { String.valueOf(pUserInfo.getUserId()) };
                        updateResult = mContext.getContentResolver().update(mUri, cv, contentValues, whereArgs);
                    }
                } catch (Exception e){
                    Log.i(TAG, "update:Error:" + e.toString());
                } catch (Error e) {
                    Log.i(TAG, "update:Error:" + e.toString());
                }
            }
            return updateResult;
        }
    }

    public boolean isExist(final int pUserId){
        synchronized (sLock) {
            Boolean result;
            try {
                String[] columns = new String[] { DBData.USER_ID };
                String selection = DBData.USER_ID + " = ? ";
                String[] whereArgs = new String[] { String.valueOf(pUserId)};
                Cursor cursor = mContext.getContentResolver().query(mUri, columns, selection, whereArgs, null);
                result = cursor.getCount() > 0 ? true : false;
                cursor.close();
            } catch (Exception e) {
                result = false;
                Log.i(TAG, "exist:Exception:" + e.toString());
            } catch (Error e) {
                result = false;
                Log.i(TAG, "exist:Error:" + e.toString());
            }
            return result;
        }
    }

    public List<UserInfo> getUserInfoList() {
        synchronized (sLock) {
            List<UserInfo> userInfoList = null;
            try{
                String orderBy = DBData.USER_CREATE_TIME + " DESC " ;
                Cursor cursor = mContext.getContentResolver().query(mUri, null, null, null, orderBy);
                if (cursor != null) {
                    userInfoList = new ArrayList<>(cursor.getCount());
                    for(cursor.moveToLast(); !cursor.isBeforeFirst(); cursor.moveToPrevious()){
                        UserInfo userInfo = toUserInfo(cursor);
                        userInfoList.add(userInfo);
                    }
                    cursor.close();
                }
            } catch (Exception e) {
                Log.i(TAG, "query:Exception:" + e.toString());
            } catch (Error e) {
                Log.i(TAG, "query:Error:" + e.toString());
            }
            return userInfoList;
        }
    }

    public UserInfo getUserInfo(final int pUserId){
        synchronized (sLock) {
            UserInfo userInfo = null;
            try {
                String selection = DBData.USER_ID + " = ? ";
                String[] whereArgs = new String[] { String.valueOf(pUserId)};
                Cursor cursor = mContext.getContentResolver().query(mUri, null, selection, whereArgs, null);
                if (cursor != null) {
                    if (cursor.moveToFirst()){
                        userInfo = toUserInfo(cursor);
                    }
                    cursor.close();
                }

            } catch (Exception e) {
                Log.i(TAG, "queryOne:Exception:" + e.toString());
            } catch (Error e) {
                Log.i(TAG, "queryOne:Error:" + e.toString());
            }
            return userInfo;
        }
    }

    public void dropTable() {
        synchronized (sLock) {
            try {
                String sql_drop_table = "DROP TABLE IF EXISTS " + DBData.TABLE_USER;
                mContext.getContentResolver().delete(mRawUri, sql_drop_table, null);
            } catch (Exception e) {
                Log.i(TAG, "dropTable:Error:" + e.toString());
            } catch (Error e) {
                Log.i(TAG, "dropTable:Error:" + e.toString());
            }
        }
    }

    private ContentValues toContentValues(ContentValues pCV, UserInfo pUserInfo) {
        if (pCV == null || pUserInfo == null){
            return pCV;
        }
        pCV.clear();
        pCV.put(DBData.USER_ID, pUserInfo.getUserId());
        pCV.put(DBData.USER_NICK_NAME, pUserInfo.getNickname());
        pCV.put(DBData.USER_PROFILE_PIC_URL, pUserInfo.getProfilePicUrl());
        pCV.put(DBData.USER_PHONE_NUM, pUserInfo.getPhoneNum());
        pCV.put(DBData.USER_EMAIL, pUserInfo.getEmail());
        pCV.put(DBData.USER_ADDRESS, pUserInfo.getAddress());
        return pCV;
    }

    private UserInfo toUserInfo(Cursor pCursor){
        UserInfo userInfo = new UserInfo();
        if (pCursor == null){
            return userInfo;
        }
        userInfo.setAutoId(pCursor.getInt(pCursor.getColumnIndex(DBData.USER_AUTO_ID)));
        userInfo.setUserId(pCursor.getInt(pCursor.getColumnIndex(DBData.USER_ID)));
        userInfo.setNickname(pCursor.getString(pCursor.getColumnIndex(DBData.USER_NICK_NAME)));
        userInfo.setProfilePicUrl(pCursor.getString(pCursor.getColumnIndex(DBData.USER_PROFILE_PIC_URL)));
        userInfo.setPhoneNum(pCursor.getString(pCursor.getColumnIndex(DBData.USER_PHONE_NUM)));
        userInfo.setEmail(pCursor.getString(pCursor.getColumnIndex(DBData.USER_EMAIL)));
        userInfo.setAddress(pCursor.getString(pCursor.getColumnIndex(DBData.USER_ADDRESS)));
        return userInfo;
    }
}

7.其中用到的UserInfo.java

public class UserInfo implements Parcelable {
    private int mAutoId;
    private int mUserId;
    private String mNickname;
    private String mProfilePicUrl;
    private String mPhoneNum;
    private String mEmail;
    private String mAddress;

    public UserInfo(int userId, String nickname, String profilePicUrl, String phoneNum, String email, String address) {
        mUserId = userId;
        mNickname = nickname;
        mProfilePicUrl = profilePicUrl;
        mPhoneNum = phoneNum;
        mEmail = email;
        mAddress = address;
    }

    public int getAutoId() {
        return mAutoId;
    }

    public void setAutoId(int autoId) {
        mAutoId = autoId;
    }

    public int getUserId() {
        return mUserId;
    }

    public void setUserId(int userId) {
        mUserId = userId;
    }

    public String getNickname() {
        return mNickname;
    }

    public void setNickname(String nickname) {
        mNickname = nickname;
    }

    public String getProfilePicUrl() {
        return mProfilePicUrl;
    }

    public void setProfilePicUrl(String profilePicUrl) {
        mProfilePicUrl = profilePicUrl;
    }

    public String getPhoneNum() {
        return mPhoneNum;
    }

    public void setPhoneNum(String phoneNum) {
        mPhoneNum = phoneNum;
    }

    public String getEmail() {
        return mEmail;
    }

    public void setEmail(String email) {
        mEmail = email;
    }

    public String getAddress() {
        return mAddress;
    }

    public void setAddress(String address) {
        mAddress = address;
    }


    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeInt(this.mAutoId);
        dest.writeInt(this.mUserId);
        dest.writeString(this.mNickname);
        dest.writeString(this.mProfilePicUrl);
        dest.writeString(this.mPhoneNum);
        dest.writeString(this.mEmail);
        dest.writeString(this.mAddress);
    }

    public UserInfo() {
    }

    protected UserInfo(Parcel in) {
        this.mAutoId = in.readInt();
        this.mUserId = in.readInt();
        this.mNickname = in.readString();
        this.mProfilePicUrl = in.readString();
        this.mPhoneNum = in.readString();
        this.mEmail = in.readString();
        this.mAddress = in.readString();
    }

    public static final Creator<UserInfo> CREATOR = new Creator<UserInfo>() {
        @Override
        public UserInfo createFromParcel(Parcel source) {
            return new UserInfo(source);
        }

        @Override
        public UserInfo[] newArray(int size) {
            return new UserInfo[size];
        }
    };

    @Override
    public String toString() {
        return "UserInfo{" +
                "mAutoId=" + mAutoId +
                ", mUserId=" + mUserId +
                ", mNickname='" + mNickname + '\'' +
                ", mProfilePicUrl='" + mProfilePicUrl + '\'' +
                ", mPhoneNum='" + mPhoneNum + '\'' +
                ", mEmail='" + mEmail + '\'' +
                ", mAddress='" + mAddress + '\'' +
                '}';
    }
}

8.测试代码

public class SampleTask implements Runnable {
    private static final String TAG = SampleTask.class.getSimpleName();
    Handler mHandler;
    Context mContext;

    public SampleTask(Context context, Handler handler) {
        super();
        mHandler = handler;
        mContext = context;
    }

    @Override
    public void run() {
        try {
            // 模拟执行某项任务，下载等
            //Thread.sleep(5000);
            // 任务完成后通知activity更新UI
            //nickname, String profilePicUrl, String phoneNum, String email, String address
            List<UserInfo> userInfoList = new ArrayList<>();
            for (int i = 0; i < 10; i++){
                UserInfo userInfo = new UserInfo(10000 +i, "于" + i, "http://www.aoaoyi.com/" + i, "1883807***" + i, "1360***"+ i + "@qq.com", "aoaoyi" + i);
                userInfoList.add(userInfo);
            }
            UserInfoDao userInfoDao = new UserInfoDao(mContext);
            userInfoDao.insertList(userInfoList);

            List<UserInfo> userInfoList1 = userInfoDao.getUserInfoList();
            for (UserInfo userInfo : userInfoList1){
                Log.i(TAG, userInfo.toString());
            }

            Message msg = prepareMessage("task completed!");
            // message将被添加到主线程的MQ中
            mHandler.sendMessageDelayed(msg, 5000);
        } catch (Exception e) {
            Log.d(TAG, "interrupted!");
        }
    }

    private Message prepareMessage(String str) {
        Message result = mHandler.obtainMessage();
        Bundle data = new Bundle();
        data.putString("message", str);
        result.setData(data);
        return result;
    }
}

到这里，ContentProvider介绍也就结束了。

希望大家继续阅读下面的文章，这样更能提高大家对知识的掌握：

希望大家共同进步，早日找到一份理想的工作，实现财务自由。