android+studio通讯录

以下是使用Android Studio实现通讯录的一般步骤：

1.创建一个新项目并添加必要的依赖项，例如SQLite数据库。

2.创建一个布局文件来显示通讯录列表。可以使用ListView来显示通讯录列表。

3.创建一个Java类来处理通讯录数据。这个类应该包含添加、删除、更新和查询通讯录数据的方法。

4.在应用程序中使用适配器将通讯录数据绑定到ListView上。

5.添加一个搜索框，以便用户可以搜索通讯录中的联系人。

6.添加一个详细视图，以便用户可以查看和编辑联系人的详细信息。

7.测试应用程序并进行必要的调试。

以下是一个简单的示例代码，用于在Android Studio中实现通讯录：

1.布局文件：

<ListView
    android:id="@+id/friend"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

2.Java类：

public class Contact {
    private int id;
    private String name;
    private String phone;

    public Contact(int id, String name, String phone) {
        this.id = id;
        this.name = name;
        this.phone = phone;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }
}

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

    private static final String TABLE_NAME = "contact";    private static final String COLUMN_ID = "id";
    private static final String COLUMN_NAME = "name";
    private static final String COLUMN_PHONE = "phone";

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

    public ContactDatabaseHelper(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) {
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        onCreate(db);
    }

    public void addContact(Contact contact) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(COLUMN_NAME, contact.getName());
        values.put(COLUMN_PHONE, contact.getPhone());

        db.insert(TABLE_NAME, null, values);
        db.close();
    }

    public List<Contact> getAllContacts() {
        List<Contact> contactList = new ArrayList<>();

        String selectQuery = "SELECT * FROM " + TABLE_NAME;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery, null);

        if (cursor.moveToFirst()) {
            do {
                Contact contact = new Contact(
                        cursor.getInt(cursor.getColumnIndex(COLUMN_ID)),
                        cursor.getString(cursor.getColumnIndex(COLUMN_NAME)),
                        cursor.getString(cursor.getColumnIndex(COLUMN_PHONE))
                );
                contactList.add(contact);
            } while (cursor.moveToNext());
        }

        cursor.close();
        db.close();

        return contactList;
    }

    public void updateContact(Contact contact) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(COLUMN_NAME, contact.getName());
        values.put(COLUMN_PHONE, contact.getPhone());

        db.update(TABLE_NAME, values, COLUMN_ID + " = ?",
                new String[]{String.valueOf(contact.getId())});

        db.close();
    }

    public void deleteContact(Contact contact) {
        SQLiteDatabase db = this.getWritableDatabase();
        db.delete(TABLE_NAME, COLUMN_ID + " = ?",
                new String[]{String.valueOf(contact.getId())});
        db.close();
    }
}

public class ContactAdapter extends ArrayAdapter<Contact> {
    private Context context;
    private List<Contact> contactList;

    public ContactAdapter(Context context, List<Contact> contactList) {
        super(context, R.layout.list_item_contact, contactList);
        this.context = context;
        this.contactList = contactList;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View rowView = inflater.inflate(R.layout.list_item_contact, parent, false);

        TextView nameTextView = rowView.findViewById(R.id.nameTextView);
        TextView phoneTextView = rowView.findViewById(R.id.phoneTextView);

        Contact contact = contactList.get(position);

        nameTextView.setText(contact.getName());
        phoneTextView.setText(contact.getPhone());

        return rowView;
    }
}

public class MainActivity extends AppCompatActivity {
    private ListView friendListView;
    private ContactDatabaseHelper dbHelper;
    private List<Contact> contactList;

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

        friendListView = findViewById(R.id.friend);
        dbHelper = new ContactDatabaseHelper(this);

        contactList = dbHelper.getAllContacts();

        ContactAdapter adapter = new ContactAdapter(this, contactList);
        friendListView.setAdapter(adapter);
    }
}