android contentprovider的例子

package com.eoeAndroid.contentProvider; import java.util.Calendar; import java.util.HashMap; import android.content.ContentProvider; import android.content.ContentUris; import android.content.ContentValues; import android.content.Context; import android.content.UriMatcher; import android.content.res.Resources; import android.database.Cursor; import android.database.SQLException; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; import android.database.sqlite.SQLiteQueryBuilder; import android.net.Uri; import android.text.TextUtils; import android.util.Log; import com.eoeAndroid.contentProvider.Diary.DiaryColumns; public class DiaryContentProvider extends ContentProvider { private static final String DATABASE_NAME = "database"; private static final int DATABASE_VERSION = 3; private static final String DIARY_TABLE_NAME = "diary"; private static final int DIARIES = 1; private static final int DIARY_ID = 2; private static final UriMatcher sUriMatcher; private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); Log.i("jinyan", "DATABASE_VERSION=" + DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { Log.i("jinyan", "onCreate(SQLiteDatabase db)"); String sql = "CREATE TABLE " + DIARY_TABLE_NAME + " (" + DiaryColumns._ID + " INTEGER PRIMARY KEY," + DiaryColumns.TITLE + " TEXT," + DiaryColumns.BODY + " TEXT," + DiaryColumns.CREATED + " TEXT" + ");"; // sql ="CREATE TABLE " + DIARY_TABLE_NAME + " (" + DiaryColumns._ID + " INTEGER PRIMARY KEY," + DiaryColumns.TITLE + " varchar(255)," + DiaryColumns.BODY + " TEXT," + DiaryColumns.CREATED + " TEXT" + ");"; // Log.i("jinyan", "sql="+sql); db.execSQL(sql); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.i("jinyan", " onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)=" + newVersion); db.execSQL("DROP TABLE IF EXISTS diary"); onCreate(db); } } private DatabaseHelper mOpenHelper; static { sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH); sUriMatcher.addURI(Diary.AUTHORITY, "diaries", DIARIES); sUriMatcher.addURI(Diary.AUTHORITY, "diaries/#", DIARY_ID); } @Override public boolean onCreate() { mOpenHelper = new DatabaseHelper(getContext()); return true; } @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { SQLiteQueryBuilder qb = new SQLiteQueryBuilder(); switch (sUriMatcher.match(uri)) { case DIARIES: qb.setTables(DIARY_TABLE_NAME); break; case DIARY_ID: qb.setTables(DIARY_TABLE_NAME); qb.appendWhere(DiaryColumns._ID + "=" + uri.getPathSegments().get(1)); break; default: throw new IllegalArgumentException("Unknown URI " + uri); } String orderBy; if (TextUtils.isEmpty(sortOrder)) { orderBy = Diary.DiaryColumns.DEFAULT_SORT_ORDER; } else { orderBy = sortOrder; } SQLiteDatabase db = mOpenHelper.getReadableDatabase(); Cursor c = qb.query(db, projection, selection, selectionArgs, null, null, orderBy); return c; } @Override public String getType(Uri uri) { switch (sUriMatcher.match(uri)) { case DIARIES: return DiaryColumns.CONTENT_TYPE; case DIARY_ID: return DiaryColumns.CONTENT_ITEM_TYPE; default: throw new IllegalArgumentException("Unknown URI " + uri); } } @Override public Uri insert(Uri uri, ContentValues initialValues) { if (sUriMatcher.match(uri) != DIARIES) { throw new IllegalArgumentException("Unknown URI " + uri); } ContentValues values; if (initialValues != null) { values = new ContentValues(initialValues); } else { values = new ContentValues(); } if (values.containsKey(Diary.DiaryColumns.CREATED) == false) { values.put(Diary.DiaryColumns.CREATED, getFormateCreatedDate()); } if (values.containsKey(Diary.DiaryColumns.TITLE) == false) { Resources r = Resources.getSystem(); values.put(Diary.DiaryColumns.TITLE, r .getString(android.R.string.untitled)); } if (values.containsKey(Diary.DiaryColumns.BODY) == false) { values.put(Diary.DiaryColumns.BODY, ""); } SQLiteDatabase db = mOpenHelper.getWritableDatabase(); long rowId = db.insert(DIARY_TABLE_NAME, DiaryColumns.BODY, values); if (rowId > 0) { Uri diaryUri = ContentUris.withAppendedId( Diary.DiaryColumns.CONTENT_URI, rowId); return diaryUri; } throw new SQLException("Failed to insert row into " + uri); } @Override public int delete(Uri uri, String where, String[] whereArgs) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); String rowId = uri.getPathSegments().get(1); return db .delete(DIARY_TABLE_NAME, DiaryColumns._ID + "=" + rowId, null); } @Override public int update(Uri uri, ContentValues values, String where, String[] whereArgs) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); String rowId = uri.getPathSegments().get(1); return db.update(DIARY_TABLE_NAME, values, DiaryColumns._ID + "=" + rowId, null); } public static String getFormateCreatedDate() { Calendar calendar = Calendar.getInstance(); String created = calendar.get(Calendar.YEAR) + "年" + calendar.get(Calendar.MONTH) + "月" + calendar.get(Calendar.DAY_OF_MONTH) + "日" + calendar.get(Calendar.HOUR_OF_DAY) + "时" + calendar.get(Calendar.MINUTE) + "分"; return created; } }