android+studio登陆注册页面源码

Android Studio 登录注册页面的源码可以分为以下几个部分：

1. 布局文件：包括登录和注册页面的布局，可以使用 XML 文件来定义。

2. Java 代码：包括登录和注册页面的逻辑处理，可以使用 Java 代码来实现。

3. 数据库：用于存储用户信息，可以使用 SQLite 数据库来实现。

以下是一个简单的登录注册页面的源码示例：

布局文件 login_activity.xml：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <EditText
        android:id="@+id/username"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Username" />

    <EditText
        android:id="@+id/password"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Password"
        android:inputType="textPassword" />

    <Button
        android:id="@+id/login_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Login" />

    <TextView
        android:id="@+id/register_link"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Don't have an account? Register here." />

</LinearLayout>

Java 代码 LoginActivity.java：

public class LoginActivity extends AppCompatActivity {

    private EditText mUsername;
    private EditText mPassword;
    private Button mLoginButton;
    private TextView mRegisterLink;

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

        mUsername = findViewById(R.id.username);
        mPassword = findViewById(R.id.password);
        mLoginButton = findViewById(R.id.login_button);
        mRegisterLink = findViewById(R.id.register_link);

        mLoginButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 登录逻辑处理
            }
        });

        mRegisterLink.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 跳转到注册页面
            }
        });
    }
}

数据库 DBHelper.java：

public class DBHelper extends SQLiteOpenHelper {

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

    private static final String TABLE_NAME = "users";
    private static final String COLUMN_ID = "id";
    private static final String COLUMN_USERNAME = "username";
    private static final String COLUMN_PASSWORD = "password";

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

    public DBHelper(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 boolean addUser(String username, String password) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(COLUMN_USERNAME, username);
        values.put(COLUMN_PASSWORD, password);
        long result = db.insert(TABLE_NAME, null, values);
        return result != -1;
    }

    public boolean checkUser(String username, String password) {
        SQLiteDatabase db = this.getReadableDatabase();
        String[] columns = {COLUMN_ID};
        String selection = COLUMN_USERNAME + " = ?" + " AND " + COLUMN_PASSWORD + " = ?";
        String[] selectionArgs = {username, password};
        Cursor cursor = db.query(TABLE_NAME, columns, selection, selectionArgs, null, null, null);
        int count = cursor.getCount();
        cursor.close();
        return count > 0;
    }
}