//import com.example.cptest.FirstProviderMetaData;
import com.example.cptest.FirstProviderMetaData.UserTableMetaData;

import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

    private Button insert = null;
    private Button query = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        insert = (Button)findViewById(R.id.insert);
        insert.setOnClickListener(new InsertOnClickListener());
        query = (Button)findViewById(R.id.query);
        query.setOnClickListener(new QueryOnClickListener());
        System.out.println(getContentResolver().getType(FirstProviderMetaData.UserTableMetaData.CONTENT_URI));
    }

    //往子表中插入一條記錄
    public class InsertOnClickListener implements OnClickListener{

        public void onClick(View arg0) {
            // TODO Auto-generated method stub   
            ContentValues values = new ContentValues();
            values.put(FirstProviderMetaData.UserTableMetaData.USER_NAME, "tornadomeet");
            //實(shí)際上使用的是ContentResolver的insert方法
            //該insert中有2個(gè)參數(shù)，第一個(gè)為代表了ContentProvider的Uri，第二個(gè)參數(shù)為要插入的值。此處的insert函數(shù)
            //一執(zhí)行，則自動(dòng)調(diào)用ContentProvider的insert方法。
            Uri uri = getContentResolver().insert(FirstProviderMetaData.UserTableMetaData.CONTENT_URI,
                    values);
            System.out.println("uri--->" +uri.toString());
        }       
    }

   
    //查詢也是采用的ContentResolver中的query方法。
    public class QueryOnClickListener implements OnClickListener{
        public void onClick(View v) {
            // TODO Auto-generated method stub       
            Cursor c = getContentResolver().query(FirstProviderMetaData.UserTableMetaData.CONTENT_URI,
                    null, null, null, null);
            while(c.moveToNext())
                System.out.println(c.getString(c.getColumnIndex(UserTableMetaData.USER_NAME)));
        }    
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
}

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;

public class DatabaseHelper extends SQLiteOpenHelper {

    private static final int  VERSON = 1;//默認(rèn)的數(shù)據(jù)庫版本

    //繼承SQLiteOpenHelper類的類必須有自己的構(gòu)造函數(shù)
    //該構(gòu)造函數(shù)4個(gè)參數(shù)，直接調(diào)用父類的構(gòu)造函數(shù)。其中第一個(gè)參數(shù)為該類本身；第二個(gè)參數(shù)為數(shù)據(jù)庫的名字；
    //第3個(gè)參數(shù)是用來設(shè)置游標(biāo)對(duì)象的，這里一般設(shè)置為null；參數(shù)四是數(shù)據(jù)庫的版本號(hào)。
    public DatabaseHelper(Context context, String name, CursorFactory factory, int verson){
        super(context, name, factory, verson);
    }

    //該構(gòu)造函數(shù)有3個(gè)參數(shù)，因?yàn)樗焉厦婧瘮?shù)的第3個(gè)參數(shù)固定為null了
    public DatabaseHelper(Context context, String name, int verson){
        this(context, name, null, verson);
    }

    //該構(gòu)造函數(shù)只有2個(gè)參數(shù)，在上面函數(shù) 的基礎(chǔ)山將版本號(hào)固定了
    public DatabaseHelper(Context context, String name){
        this(context, name, VERSON);
    }

    //該函數(shù)在數(shù)據(jù)庫第一次被建立時(shí)調(diào)用
    @Override
    public void onCreate(SQLiteDatabase arg0) {
        // TODO Auto-generated method stub
        System.out.println("create a database");
        //execSQL()為執(zhí)行參數(shù)里面的SQL語句，因此參數(shù)中的語句需要符合SQL語法,這里是創(chuàng)建一個(gè)表
        //arg0.execSQL("create table user1(id int, name varchar(20))");下面的語句格式是與該句類似
//        arg0.execSQL("create table" + FirstProviderMetaData.USERS_TABLE_NAME
//                + "(" + FirstProviderMetaData.UserTableMetaData._ID
//                + " INTEGER PRIMARY KEY AUTOINCREMENT," +   //ID類型為自增長(zhǎng)的整型
//                FirstProviderMetaData.UserTableMetaData.USER_NAME + " varchar(20));"
//                );
    //    arg0.execSQL("create table user1(id int, name varchar(20))");
        arg0.execSQL("create table" + FirstProviderMetaData.USERS_TABLE_NAME + "("
                + FirstProviderMetaData.UserTableMetaData._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
                +FirstProviderMetaData.UserTableMetaData.USER_NAME + " varchar(20))");
        System.out.println("create a database ok");
    }

    @Override
    public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
        // TODO Auto-generated method stub
        System.out.println("update a database");
    }

}

import android.net.Uri;
import android.provider.BaseColumns;

public class FirstProviderMetaData {

    //這里的AUTHORTY為包的全名+ContentProvider子類的全名
    public static final String AUTHORTY = "com.example.cptest.FirstContentProvider";
    //數(shù)據(jù)庫的名稱
    public static final String DATABASE_NAME = "FisrtProvider.db";
    //數(shù)據(jù)庫的版本號(hào)
    public static final int DATABASE_VERSION = 1;
    //數(shù)據(jù)庫中的表名
    public static final String USERS_TABLE_NAME = "users";
    //表中的字表
    public static final class UserTableMetaData implements BaseColumns{
        //子表名
        public static final String TABLE_NAME = "users";
        //CONTENT_URI為常量Uri; parse是將文本轉(zhuǎn)換成Uri
        public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORTY + "/users");
        //返回ContentProvider中表的數(shù)據(jù)類型
        public static final String CONTENT_TYPE = "vnd.android.cursor.dir/vnd.firstprovider.user";
        //返回ContentProvider表中item的數(shù)據(jù)類型
        public static final String CONTENT_TYPE_ITEM = "vnd.android.cursor.item/vnd.firstprovider.user";
        //子表列名
        public static final String USER_NAME = "name";
        //表中記錄的默認(rèn)排序算法，這里是降序排列
        public static final String DEFAULT_SORT_ORDER = "_id desc";

       
    }

}

import java.util.HashMap;

import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteQueryBuilder;
import android.net.Uri;
import android.text.TextUtils;

import com.example.cptest.FirstProviderMetaData.UserTableMetaData;

public class FirstContentProvider extends ContentProvider {

    //定義一個(gè)UriMatcher類對(duì)象，用來匹配Uri的。
    public static final UriMatcher uriMatcher;
    //組時(shí)的ID
    public static final int INCOMING_USER_COLLECTION = 1;
    //單個(gè)時(shí)的ID
    public static final int INCOMING_USER_SIGNAL = 2;
    private DatabaseHelper dh;//定義一個(gè)DatabaseHelper對(duì)象
    static{
        uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);//UriMatcher.NO_MATCH表示不匹配任何路徑的返回碼
        uriMatcher.addURI(FirstProviderMetaData.AUTHORTY, "users", INCOMING_USER_COLLECTION);
        uriMatcher.addURI(FirstProviderMetaData.AUTHORTY, "users/#", INCOMING_USER_SIGNAL);//后面加了#表示為單個(gè)
    }

    public static HashMap<String, String> userProjectionMap;//新建一個(gè)HashMap,后面執(zhí)行插入操作時(shí)有用
    static
    {
        userProjectionMap = new HashMap<String, String>();
        //這里可以直接調(diào)用另外一個(gè)類的public變量，這里put里面的2個(gè)參數(shù)一樣，
        //是因?yàn)檫@里是給數(shù)據(jù)庫表中的列取別名，因此取的是一樣的名字
        userProjectionMap.put(UserTableMetaData._ID, UserTableMetaData._ID);
        userProjectionMap.put(UserTableMetaData.USER_NAME, UserTableMetaData.USER_NAME);
    }

    //得到ContentProvider的數(shù)據(jù)類型，返回的參數(shù)Uri所代表的數(shù)據(jù)類型
    @Override
    public String getType(Uri arg0) {
        // TODO Auto-generated method stub
        System.out.println("getType");
        switch(uriMatcher.match(arg0)){
        //matcher滿足Uri的前2項(xiàng)（即協(xié)議+路徑）為第1種情況時(shí)，switch語句的值為Uri的第3項(xiàng)，此處為INCOMING_USER_COLLECTION
        case INCOMING_USER_COLLECTION:
            return UserTableMetaData.CONTENT_TYPE;
        case INCOMING_USER_SIGNAL://同上
            return UserTableMetaData.CONTENT_TYPE_ITEM;
        default:
            throw new IllegalArgumentException("Unknown URI" + arg0);//throw是處理異常的，java中的語法
        }
    }

    @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        // TODO Auto-generated method stub
        System.out.println("delete");
        return 0;
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection,
            String[] selectionArgs) {
        // TODO Auto-generated method stub
        System.out.println("update");
        return 0;
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {
        // TODO Auto-generated method stub
        System.out.println("insert");
//        dh = new DatabaseHelper(getContext(), FirstProviderMetaData.DATABASE_NAME);
        SQLiteDatabase db = dh.getWritableDatabase();
        long rowId = db.insert(UserTableMetaData.TABLE_NAME, null, values);
//        System.out.println("insert  OK");
//        System.out.println("" + rowId);
        if(rowId > 0){           
            //發(fā)出通知給監(jiān)聽器，說明數(shù)據(jù)已經(jīng)改變
            //ContentUris為工具類
            Uri insertedUserUri = ContentUris.withAppendedId(UserTableMetaData.CONTENT_URI, rowId);
            getContext().getContentResolver().notifyChange(insertedUserUri, null);

            return insertedUserUri;
        }
        throw new SQLException("Failed to insert row into" + uri);
    }

    //回調(diào)函數(shù)，在ContentProvider創(chuàng)建的時(shí)候調(diào)用
    @Override
    public boolean onCreate() {
        // TODO Auto-generated method stub
        System.out.println("onCreate");
        dh = new DatabaseHelper(getContext(), FirstProviderMetaData.DATABASE_NAME);//創(chuàng)建1個(gè)DatabaseHelper對(duì)象
        return true;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection,
            String[] selectionArgs, String sortOrder) {
        // TODO Auto-generated method stub
        System.out.println("query");
        SQLiteQueryBuilder qb = new SQLiteQueryBuilder();
        switch(uriMatcher.match(uri)){
        case INCOMING_USER_COLLECTION:
            qb.setTables(UserTableMetaData.TABLE_NAME);//設(shè)置表的名稱
            qb.setProjectionMap(userProjectionMap);//其中userProjectionMap為上面建立好了的hashmap
            break;
        case INCOMING_USER_SIGNAL:
            qb.setTables(UserTableMetaData.TABLE_NAME);//設(shè)置表的名稱
            qb.setProjectionMap(userProjectionMap);//其中userProjectionMap為上面建立好了的hashmap
            //uri.getPathSegments()得到Path部分，即把uri的協(xié)議+authory部分去掉，把剩下的部分分段獲取，這里取第
            //一部分
            qb.appendWhere(UserTableMetaData._ID + "=" +uri.getPathSegments().get(1));//設(shè)置where條件
            break;
        }
        //排序
        String orderBy;
        if(TextUtils.isEmpty(sortOrder)){
            orderBy = UserTableMetaData.DEFAULT_SORT_ORDER;//傳入的排序參數(shù)為空的時(shí)候采用默認(rèn)的排序
        }
        else{
            orderBy = sortOrder;//不為空時(shí)用指定的排序方法進(jìn)行排序
        }
        SQLiteDatabase db = dh.getWritableDatabase();
        //采用傳入的參數(shù)進(jìn)行查詢
        Cursor c = qb.query(db, projection, selection, selectionArgs, null, null, sortOrder);
        //發(fā)出通知
        c.setNotificationUri(getContext().getContentResolver(), uri);
        return c;
    }

}