我在Android中創建了一個示例SQLite數據庫,它將條目讀入ListView。我將添加代碼,以便單擊時,每個ListView項目都會啓動一個新的活動以顯示更多信息。我如何從另一個活動中對此數據庫運行查詢?由於從另一個類訪問SQLite數據庫
public class Database extends ListActivity {
private final String SAMPLE_DB_NAME = "myFriendsDb";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ArrayList<String> results = new ArrayList<String>();
SQLiteDatabase db = null;
try {
db = this.openOrCreateDatabase(SAMPLE_DB_NAME, MODE_PRIVATE, null);
db.execSQL("CREATE TABLE IF NOT EXISTS people" +
" (LastName VARCHAR, FirstName VARCHAR," +
" Country VARCHAR, Age INT(3));");
db.execSQL("INSERT INTO people" +
" Values ('Jones','Bob','UK',30);");
db.execSQL("INSERT INTO people" +
" Values ('Smith','John','UK',40);");
db.execSQL("INSERT INTO people" +
" Values ('Thompson','James','UK',50);");
Cursor c = db.rawQuery("SELECT FirstName, LastName FROM people", null);
if (c != null) {
if (c.moveToFirst()) {
do {
String firstName = c.getString(c.getColumnIndex("FirstName"));
String lastName = c.getString(c.getColumnIndex("LastName"));
results.add("" + firstName + " " + lastName);
}while (c.moveToNext());
}
}
this.setListAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,results));
} catch (SQLiteException se) {
Log.e(getClass().getSimpleName(), "Could not create or Open the database");
} finally {
if (db != null)
db.execSQL("DELETE FROM people");
db.close();
}
}
http://www.vogella.com/articles/AndroidSQLite/article.html#databasetutorial是關於各種SQLite相關事情的不錯教程。您應該特別關注用於打開數據庫的'SQLiteOpenHelper'和用於訪問數據的DataSource類。 – zapl 2012-04-28 22:55:35