contentProvider模板

package com.example.qunzheng.todolist.provider;

import android.content.ContentProvider;

import android.content.ContentUris;

import android.content.ContentValues;

import android.content.Context;

import android.content.UriMatcher;

import android.database.Cursor;

import android.database.sqlite.SQLiteDatabase;

import android.database.sqlite.SQLiteOpenHelper;

import android.database.sqlite.SQLiteQueryBuilder;

import android.net.Uri;

import android.text.TextUtils;

/**

 * Created by QunZheng on 2015/3/9.

 */

public class EarthquakeProvider extends ContentProvider {

    public static final Uri CONTENT_URI = Uri.parse("content://com.qunzheng.earthquakeprovider/earthquakes");

    public static final String KEY_ID = "_id";

    public static final String KEY_DATE = "date";

    public static final String KEY_DETAILS = "details";

    public static final String KEY_SUMMARY = "summary";

    public static final String KEY_LOCATION_LAT = "latitude";

    public static final String KEY_LOCATION_LNG = "longitude";

    public static final String KEY_LINK = "link";

    public static final String KEY_MAGNITUDE = "magnitude";

    private EarthquakeDatabaseHelper sqLiteOpenHelper = null;

    private static final int ALL_ROWS = 1;

    private static final int SINGLE_ROW = 2;

    private static UriMatcher matcher = null;

    static {

        matcher = new UriMatcher(UriMatcher.NO_MATCH);

        matcher.addURI("com.qunzheng.earthquakeprovider","earthquakes",ALL_ROWS);

        matcher.addURI("com.qunzheng.earthquakeprovider","earthquakes/#",SINGLE_ROW);

    }

    @Override

    public boolean onCreate() {

        sqLiteOpenHelper = new EarthquakeDatabaseHelper(getContext(), EarthquakeDatabaseHelper.DATABASE_NAME, null, EarthquakeDatabaseHelper.DATABASE_VERSION);

        return true;

    }

    @Override

    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {

        SQLiteDatabase db = sqLiteOpenHelper.getWritableDatabase();

        SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();

        queryBuilder.setTables(EarthquakeDatabaseHelper.DATABASE_TABLE);

        switch (matcher.match(uri)) {

            case SINGLE_ROW:

                String rowId = uri.getPathSegments().get(1);

                queryBuilder.appendWhere(KEY_ID + "=" + rowId);

                break;

        }

        String orderBy;

        if (TextUtils.isEmpty(sortOrder)) {

            orderBy = KEY_DATE;

        }else{

            orderBy = sortOrder;

        }

        return queryBuilder.query(db,projection,selection,selectionArgs,null,null,orderBy);

    }

    @Override

    public String getType(Uri uri) {

        switch (matcher.match(uri)) {

            case ALL_ROWS:

                return "vnd.android.cursor.dir/vnd.qunzheng.earthquakes";

            case SINGLE_ROW:

                return "vnd.android.cursor.item/vnd.qunzheng.earthquakes";

            default:

                throw new IllegalArgumentException("Unsupport Uri:" + uri);

        }

    }

    @Override

    public Uri insert(Uri uri, ContentValues values) {

        SQLiteDatabase db = sqLiteOpenHelper.getWritableDatabase();

        long id = db.insert(EarthquakeDatabaseHelper.DATABASE_TABLE, null, values);

        //数据插入成功

        if (id > -1) {

            Uri resultUri = ContentUris.withAppendedId(CONTENT_URI, id);

            getContext().getContentResolver().notifyChange(resultUri, null);

            return resultUri;

        }else{

        }

        return null;

    }

    @Override

    public int delete(Uri uri, String selection, String[] selectionArgs) {

        SQLiteDatabase db = sqLiteOpenHelper.getWritableDatabase();

        switch (matcher.match(uri)) {

            case SINGLE_ROW:

                String id = uri.getPathSegments().get(1);

                selection = KEY_ID + "=" + id +

                        (TextUtils.isEmpty(selection) ? "" : (" and ("+ selection +")"));

                break;

        }

        if (selection == null) {

            selection = "1";

        }

        int resultRows = db.delete(EarthquakeDatabaseHelper.DATABASE_TABLE, selection, selectionArgs);

        getContext().getContentResolver().notifyChange(uri, null);

        return resultRows;

    }

    @Override

    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {

        SQLiteDatabase db = sqLiteOpenHelper.getReadableDatabase();

        switch (matcher.match(uri)) {

            case SINGLE_ROW:

                String id = uri.getPathSegments().get(1);

                selection = KEY_ID + "=" + id +

                        (TextUtils.isEmpty(selection) ? "" : (" and ("+ selection +")"));

                break;

        }

        int resultRows = db.update(EarthquakeDatabaseHelper.DATABASE_TABLE, values, selection, selectionArgs);

        getContext().getContentResolver().notifyChange(uri, null);

        return resultRows;

    }

    private static class EarthquakeDatabaseHelper extends SQLiteOpenHelper{

        public static final String DATABASE_NAME = "earthquake.db";

        public static final int DATABASE_VERSION = 1;

        public static final String DATABASE_TABLE = "earthQuake";

        private static final String TABLE_CREATE = "create table " +

                DATABASE_TABLE + " (" + KEY_ID + " integer primary key autoincrement, " +

                KEY_DATE + " INTEGER, " +

                KEY_LINK + " text, " +

                KEY_LOCATION_LAT + " FLOAT, " +

                KEY_LOCATION_LNG + " FLOAT, " +

                KEY_SUMMARY + " TEXT, " +

                KEY_MAGNITUDE + " FLOAT, " +

                KEY_DETAILS + " text)";

        public EarthquakeDatabaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {

            super(context, name, factory, version);

        }

        @Override

        public void onCreate(SQLiteDatabase db) {

            db.execSQL(TABLE_CREATE);

        }

        @Override

        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

        }

    }

}