android查sqlite并显示_android studio从Sqlite数据库检索数据并将其显示为textview

要从SQLite数据库检索数据并将其显示在Android应用程序中，您可以按照以下步骤进行操作：

1. 创建一个SQLite数据库并创建一个表。

2. 向表中插入数据。

3. 在Android应用程序中使用Cursor对象检索数据。

4. 将数据显示在TextView中。

以下是示例代码：

1. 创建SQLite数据库并创建表：

public class DatabaseHelper extends SQLiteOpenHelper {
    private static final String DATABASE_NAME = "my_database.db";
    private static final int DATABASE_VERSION = 1;

    private static final String TABLE_NAME = "my_table";
    private static final String COLUMN_ID = "id";
    private static final String COLUMN_NAME = "name";
    private static final String COLUMN_AGE = "age";

    private static final String CREATE_TABLE =
            "CREATE TABLE " + TABLE_NAME + " (" +
                    COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
                    COLUMN_NAME + " TEXT, " +
                    COLUMN_AGE + " INTEGER);";

    public DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(CREATE_TABLE);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // Handle upgrade
    }
}

2. 向表中插入数据：

DatabaseHelper dbHelper = new DatabaseHelper(this);
SQLiteDatabase db = dbHelper.getWritableDatabase();

ContentValues values = new ContentValues();
values.put(DatabaseHelper.COLUMN_NAME, "John Doe");
values.put(DatabaseHelper.COLUMN_AGE, 30);

long newRowId = db.insert(DatabaseHelper.TABLE_NAME, null, values);

3. 使用Cursor对象检索数据：

DatabaseHelper dbHelper = new DatabaseHelper(this);
SQLiteDatabase db = dbHelper.getReadableDatabase();

String[] projection = {
        DatabaseHelper.COLUMN_NAME,
        DatabaseHelper.COLUMN_AGE
};

String selection = DatabaseHelper.COLUMN_NAME + " = ?";
String[] selectionArgs = { "John Doe" };

Cursor cursor = db.query(
        DatabaseHelper.TABLE_NAME,   // The table to query
        projection,                  // The array of columns to return (pass null to get all)
        selection,                   // The columns for the WHERE clause
        selectionArgs,               // The values for the WHERE clause
        null,                        // Don't group the rows
        null,                        // Don't filter by row groups
        null                         // The sort order
);

4. 将数据显示在TextView中：

if (cursor.moveToFirst()) {
    String name = cursor.getString(cursor.getColumnIndex(DatabaseHelper.COLUMN_NAME));
    int age = cursor.getInt(cursor.getColumnIndex(DatabaseHelper.COLUMN_AGE));

    textView.setText(name + " is " + age + " years old.");
}

cursor.close();

希望这可以帮助您开始从SQLite数据库检索数据并将其显示在Android应用程序中。