5.2实验中列表中姓名来自通过 ContentResolver 读取实验 5.1 应用程序中所实现的 ContentProvider。用代码怎么实现

好的，那我来回答你的问题：

首先，我们需要在5.1实验中实现一个ContentProvider用于提供数据。这个ContentProvider应该至少包含一个表，可以使用SQLiteOpenHelper来创建和管理这个表。在这个表中，我们需要存储姓名和其他有关信息。下面是一个简单的例子：

public class MyContentProvider extends ContentProvider {

    private static final String DATABASE_NAME = "mydatabase.db";
    private static final int DATABASE_VERSION = 1;

    private static final String TABLE_NAME = "mytable";
    private static final String COLUMN_NAME_ID = "_id";
    private static final String COLUMN_NAME_NAME = "name";
    private static final String COLUMN_NAME_INFO = "info";

    private static final String CREATE_TABLE =
            "CREATE TABLE " + TABLE_NAME + " (" +
                    COLUMN_NAME_ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
                    COLUMN_NAME_NAME + " TEXT," +
                    COLUMN_NAME_INFO + " TEXT)";

    private SQLiteDatabase db;

    @Override
    public boolean onCreate() {
        MyDatabaseHelper helper = new MyDatabaseHelper(getContext(), DATABASE_NAME, null, DATABASE_VERSION);
        db = helper.getWritableDatabase();
        return true;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
        return db.query(TABLE_NAME, projection, selection, selectionArgs, null, null, sortOrder);
    }

    @Override
    public String getType(Uri uri) {
        return null;
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {
        long id = db.insert(TABLE_NAME, null, values);
        return ContentUris.withAppendedId(uri, id);
    }

    @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        return db.delete(TABLE_NAME, selection, selectionArgs);
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
        return db.update(TABLE_NAME, values, selection, selectionArgs);
    }

    private static class MyDatabaseHelper extends SQLiteOpenHelper {

        public MyDatabaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
            super(context, name, factory, version);
        }

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

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
            onCreate(db);
        }
    }
}

接下来，在5.2实验中，我们需要使用ContentResolver来读取这个ContentProvider提供的数据。假设我们要显示一个列表，其中包含所有的姓名，我们可以这样做：

public class MainActivity extends AppCompatActivity {

    private ListView listView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listView = findViewById(R.id.list_view);
        Cursor cursor = getContentResolver().query(Uri.parse("content://com.example.mycontentprovider/mytable"), new String[]{"_id", "name"}, null, null, null);
        SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1, cursor, new String[]{"name"}, new int[]{android.R.id.text1});
        listView.setAdapter(adapter);
    }
}

这样就可以从ContentProvider中读取所有的姓名，并显示在一个列表中了。