ContentProvider测试程序

package hx.android.test; 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; public class MyContentProvider extends ContentProvider { private static final String TABLE_NAME = "mytable"; private static final int TABLES = 1; private static final int TABLE_ID = 2; private static final UriMatcher sUriMatcher ; static{//注册需要匹配的Uri sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH); sUriMatcher.addURI(Mytable.MyColumns.AUTHORITY, "mytable", TABLES); sUriMatcher.addURI(Mytable.MyColumns.AUTHORITY, "mytable/#", TABLE_ID); /** * 下面会用到辅助类ContentUris 的两个实用方法 * withAppendedId(uri, id)用于为路径加上ID部分 * parseId(uri)方法用于从路径中获取ID部分 */ }; @Override public int delete(Uri uri, String arg1, String[] arg2) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); String rowId = uri.getPathSegments().get(1); return db.delete(TABLE_NAME, Mytable.MyColumns._ID + "=" + rowId, null); } @Override public String getType(Uri uri) { switch (sUriMatcher.match(uri)) { case TABLES: return Mytable.MyColumns.CONTENT_TYPE; case TABLE_ID: return Mytable.MyColumns.CONTENT_ITEM_TYPE; default: throw new IllegalArgumentException("Unknown URI " + uri); } } int i = 1; @Override public Uri insert(Uri uri, ContentValues initialValues) { // TODO Auto-generated method stub if (sUriMatcher.match(uri) != TABLES) { throw new IllegalArgumentException("Unknown URI " + uri); } ContentValues values; if (initialValues != null) { values = new ContentValues(initialValues); } else { values = new ContentValues(); } if (values.containsKey(Mytable.MyColumns._ID) == false) { values.put(Mytable.MyColumns._ID, i); i++; } if (values.containsKey(Mytable.MyColumns.TITLE) == false) { values.put(Mytable.MyColumns.TITLE, "title1"); } if (values.containsKey(Mytable.MyColumns.BODY) == false) { values.put(Mytable.MyColumns.BODY,"body1"); } if (values.containsKey(Mytable.MyColumns.NAME) == false) { values.put(Mytable.MyColumns.NAME, "name1"); } SQLiteDatabase db = mOpenHelper.getWritableDatabase(); long rowId = db.insert(TABLE_NAME, Mytable.MyColumns.BODY, values); if (rowId > 0) { Uri myUri= ContentUris.withAppendedId(Mytable.MyColumns.CONTENT_URI, rowId); return myUri;//返回值为一个uri } throw new SQLException("Failed to insert row into " + uri); } DatabaseHelper mOpenHelper ; @Override public boolean onCreate() { // TODO Auto-generated method stub mOpenHelper = new DatabaseHelper(getContext()); return true; } @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { SQLiteQueryBuilder qb = new SQLiteQueryBuilder();//是一个构造SQL查询语句的辅助类 switch (sUriMatcher.match(uri)) { case TABLES: qb.setTables(TABLE_NAME); break; case TABLE_ID: qb.setTables(TABLE_NAME); qb.appendWhere(Mytable.MyColumns._ID + "=" + uri.getPathSegments().get(1)); break; default: throw new IllegalArgumentException("Unknown URI " + uri); } // String orderBy = null; // if (TextUtils.isEmpty(sortOrder)) { // orderBy = Mytable.MyColumns.DEFAULT_SORT_ORDER; // } else { // orderBy = sortOrder; // } SQLiteDatabase db = mOpenHelper.getReadableDatabase(); Cursor c = qb.query(db, projection, selection, selectionArgs, null, null, sortOrder); return c; } @Override public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { SQLiteDatabase db = mOpenHelper.getWritableDatabase(); String rowId = uri.getPathSegments().get(1); return db.update(TABLE_NAME, values, Mytable.MyColumns._ID + "=" + rowId, null); } }