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) {

        }
    }
}