ContentProvider使用方法demo

package com.jacp.demo.provider; 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.jacp.database.DatabaseHelper; /** * 对programmer和leader表进行操作的ContentProvider * @author jacp * */ public class CommonProvider extends ContentProvider { private static HashMap<String, String> sprogrammersProjectionMap; private static final int PROGRAMMERS = 1; private static final int PROGRAMMERS_ID = 2; // 这里要增加匹配项 private static final int LEADERS = 3; private static final int LEADERS_ID = 4; private static final UriMatcher sUriMatcher; private DatabaseHelper mOpenHelper; @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(); String orderBy; switch (sUriMatcher.match(uri)) { // 这里要对不同表的匹配结果做不同处理 case LEADERS: case LEADERS_ID: qb.setTables(Provider.LeaderColumns.TABLE_NAME); // If no sort order is specified use the default if (TextUtils.isEmpty(sortOrder)) { orderBy = Provider.LeaderColumns.DEFAULT_SORT_ORDER; } else { orderBy = sortOrder; } break; case PROGRAMMERS: case PROGRAMMERS_ID: qb.setTables(Provider.ProgrammerColumns.TABLE_NAME); // If no sort order is specified use the default if (TextUtils.isEmpty(sortOrder)) { orderBy = Provider.ProgrammerColumns.DEFAULT_SORT_ORDER; } else { orderBy = sortOrder; } break; default: throw new IllegalArgumentException("Unknown URI " + uri); } switch (sUriMatcher.match(uri)) { case LEADERS: case PROGRAMMERS: qb.setProjectionMap(sprogrammersProjectionMap); break; case PROGRAMMERS_ID: qb.setProjectionMap(sprogrammersProjectionMap); qb.appendWhere(Provider.ProgrammerColumns._ID + "=" + uri.getPathSegments().get(1)); break; case LEADERS_ID: qb.setProjectionMap(sprogrammersProjectionMap); qb.appendWhere(Provider.LeaderColumns._ID + "=" + uri.getPathSegments().get(1)); break; default: throw new IllegalArgumentException("Unknown URI " + uri); } // Get the database and run the query SQLiteDatabase db = mOpenHelper.getReadableDatabase(); Cursor c = qb.query(db, projection, selection, selectionArgs, null, null, orderBy); // Tell the cursor what uri to watch, so it knows when its source data changes c.setNotificationUri(getContext().getContentResolver(), uri); return c; } @Override public String getType(Uri uri) { switch (sUriMatcher.match(uri)) { // 这里也要增加匹配项 case LEADERS: case PROGRAMMERS: return Provider.CONTENT_TYPE; case PROGRAMMERS_ID: case LEADERS_ID: return Provider.CONTENT_ITEM_TYPE; default: throw new IllegalArgumentException("Unknown URI " + uri); } } @Override public Uri insert(Uri uri, ContentValues initialValues) { ContentValues values; if (initialValues != null) { values = new ContentValues(initialValues); } else { values = new ContentValues(); } String tableName = ""; String nullColumn = ""; switch (sUriMatcher.match(uri)) { // 这里要对不同表的匹配结果做不同处理 case LEADERS: tableName = Provider.LeaderColumns.TABLE_NAME; nullColumn = Provider.LeaderColumns.NAME; // Make sure that the fields are all set if (values.containsKey(Provider.LeaderColumns.NAME) == false) { values.put(Provider.LeaderColumns.NAME, ""); } if (values.containsKey(Provider.LeaderColumns.TITLE) == false) { values.put(Provider.LeaderColumns.TITLE, ""); } if (values.containsKey(Provider.LeaderColumns.LEVEL) == false) { values.put(Provider.LeaderColumns.LEVEL, 0); } break; case PROGRAMMERS: tableName = Provider.ProgrammerColumns.TABLE_NAME; nullColumn = Provider.ProgrammerColumns.NAME; // Make sure that the fields are all set if (values.containsKey(Provider.ProgrammerColumns.NAME) == false) { values.put(Provider.ProgrammerColumns.NAME, ""); } if (values.containsKey(Provider.ProgrammerColumns.AGE) == false) { values.put(Provider.ProgrammerColumns.AGE, 0); } break; default: // Validate the requested uri throw new IllegalArgumentException("Unknown URI " + uri); } SQLiteDatabase db = mOpenHelper.getWritableDatabase(); long rowId = db.insert(tableName, nullColumn, values); if (rowId > 0) { Uri noteUri = ContentUris.withAppendedId(uri, rowId); getContext().getContentResolver().notifyChange(noteUri, null); return noteUri; } throw new SQLException("Failed to insert row into " + uri); } @Override public int delete(Uri uri, String where, String[] whereArgs) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); int count; switch (sUriMatcher.match(uri)) { // 这里要对不同表的匹配结果做不同处理，注意下面用到的表名不要弄错了 case PROGRAMMERS: count = db.delete(Provider.ProgrammerColumns.TABLE_NAME, where, whereArgs); break; case PROGRAMMERS_ID: String programmerId = uri.getPathSegments().get(1); count = db.delete(Provider.ProgrammerColumns.TABLE_NAME, Provider.ProgrammerColumns._ID + "=" + programmerId + (!TextUtils.isEmpty(where) ? " AND (" + where + ')' : ""), whereArgs); break; case LEADERS: count = db.delete(Provider.LeaderColumns.TABLE_NAME, where, whereArgs); break; case LEADERS_ID: String leaderId = uri.getPathSegments().get(1); count = db.delete(Provider.LeaderColumns.TABLE_NAME, Provider.LeaderColumns._ID + "=" + leaderId + (!TextUtils.isEmpty(where) ? " AND (" + where + ')' : ""), whereArgs); break; default: throw new IllegalArgumentException("Unknown URI " + uri); } getContext().getContentResolver().notifyChange(uri, null); return count; } @Override public int update(Uri uri, ContentValues values, String where, String[] whereArgs) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); int count; switch (sUriMatcher.match(uri)) { // 这里要对不同表的匹配结果做不同处理，注意下面用到的表名不要弄错了 case PROGRAMMERS: count = db.update(Provider.ProgrammerColumns.TABLE_NAME, values, where, whereArgs); break; case PROGRAMMERS_ID: String noteId = uri.getPathSegments().get(1); count = db.u