安卓实现登录与注册界面

使用Intent与Bundle传递数据

登录界面login.xml

1.使用Relativelayout相对布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="20dp"
    android:paddingTop="20dp"
    >

    <TextView
        android:id="@+id/tv_username"
        style="@style/intent_login_textview"
        android:text="@string/username"
        />

    <EditText
        android:id="@+id/et_username"
        style="@style/intent_login_edittext"
        android:layout_toRightOf="@id/tv_username"
        android:hint="填写用户名" />

    <TextView
        android:id="@+id/tv_password"
        style="@style/intent_login_textview"
        android:layout_below="@id/tv_username"
        android:text="@string/password"
        android:layout_marginTop="20dp"/>

    <EditText
        android:id="@+id/et_passsword"
        style="@style/intent_login_edittext"
        android:layout_below="@id/et_username"
        android:layout_toRightOf="@id/tv_password"
        android:hint="填写密码" />
    <Button
        android:id="@+id/btn_register"
        android:layout_marginTop="100dp"
        style="@style/intent_login_button"
        android:layout_marginLeft="40dp"
        android:text="注册"
       />
    <Button
        android:id="@+id/btn_login"
        android:layout_marginTop="100dp"
        android:layout_marginLeft="200dp"
        style="@style/intent_login_button"
        android:text="登录"
        />
</RelativeLayout>

2.样式,themes.xml中

 <style name="intent_login_textview">
        <item name="android:layout_width">50dp</item>
        <item name="android:layout_height">wrap_content</item>
        <item name="textAllCaps">false</item>
        <item name="android:textColor">@color/black</item>
        <item name="android:textSize">15sp</item>
        <item name="android:textStyle">normal</item>
    </style>
    <style name="intent_login_edittext">
        <item name="android:layout_width">match_parent</item>
        <item name="android:layout_height">wrap_content</item>
        <item name="textAllCaps">false</item>
        <item name="android:textColor">@color/black</item>
        <item name="android:textSize">10sp</item>
        <item name="android:textStyle">normal</item>
    </style>
    <style name="intent_login_button">
        <item name="android:layout_width">wrap_content</item>
        <item name="android:layout_height">wrap_content</item>
        <item name="textAllCaps">false</item>
        <item name="android:textColor">@color/black</item>
        <item name="android:textSize">20sp</item>
        <item name="android:textStyle">normal</item>

    </style>

LoginActivity.java

public class LoginActivity extends AppCompatActivity {
    private EditText et_password, et_username;
    private Button btn_register, btn_login;
    private String dq_name, dq_password;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);//设置Activity显示的布局
        et_password = findViewById(R.id.et_passsword);//获取布局中的控件对象
        et_username = findViewById(R.id.et_username);
        btn_login = findViewById(R.id.btn_login);
        btn_register = findViewById(R.id.btn_register);
        Btnlitener btnlistener = new Btnlitener();

        btn_login.setOnClickListener(btnlistener);
        btn_register.setOnClickListener(btnlistener);



    }

    private class Btnlitener implements View.OnClickListener {

        @Override
        public void onClick(View v) {
            Intent intent;
            switch (v.getId()) {
                case R.id.btn_register:
                    String username = et_username.getText().toString();
                    String password = et_password.getText().toString();
                    intent = new Intent(LoginActivity.this, RegisterActivity.class);
                    intent.putExtra("username", username);
                    intent.putExtra("password", password);
                    startActivity(intent);
                    break;
                case R.id.btn_login:

                    String username1 = et_username.getText().toString();
                    String password1 = et_password.getText().toString();
                    intent = getIntent();
                    Bundle bundle = intent.getExtras();
                    dq_name = bundle.getString("dq_name");
                    dq_password = bundle.getString("dq_password");
                    if (username1.equals("")||password1.equals("")){
                        Toast.makeText(LoginActivity.this, "用户名或密码不能为空", Toast.LENGTH_SHORT).show();

                    }else {
                        if (username1.equals(dq_name) && (password1.equals(dq_password))) {
                            startActivity(new Intent(LoginActivity.this, NextActivity.class));
                        } else {
                            Toast.makeText(LoginActivity.this, "用户名或密码错误", Toast.LENGTH_SHORT).show();
                        }
                    }
                    break;
            }
        }
    }

}

register注册.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="20dp"
    android:paddingTop="20dp"
    >

    <TextView
        android:id="@+id/tv_username"
        style="@style/intent_login_textview"
        android:text="@string/username"
        />

    <EditText
        android:id="@+id/et_username"
        style="@style/intent_login_edittext"
        android:layout_toRightOf="@id/tv_username"
        android:hint="填写用户名" />

    <TextView
        android:id="@+id/tv_password"
        style="@style/intent_login_textview"
        android:layout_below="@id/tv_username"
        android:text="@string/password"
        android:layout_marginTop="20dp"/>

    <EditText
        android:id="@+id/et_passsword"
        style="@style/intent_login_edittext"
        android:layout_below="@id/et_username"
        android:layout_toRightOf="@id/tv_password"
        android:hint="填写密码" />
    <TextView
        android:id="@+id/tv_repassword"
        style="@style/intent_login_textview"
        android:layout_below="@id/tv_password"
        android:text="@string/repassword"
        android:layout_marginTop="20dp"/>

    <EditText
        android:id="@+id/et_repasssword"
        style="@style/intent_login_edittext"
        android:layout_below="@id/et_passsword"
        android:layout_toRightOf="@id/tv_repassword"
        android:hint="再次填写密码" />
    <Button
        android:id="@+id/btn_confirm"
        android:layout_marginTop="150dp"
        style="@style/intent_login_button"
        android:layout_marginLeft="40dp"
        android:text="确认"
        />
    <Button
        android:id="@+id/btn_cancel"
        android:layout_marginTop="150dp"
        android:layout_marginLeft="200dp"
        style="@style/intent_login_button"
        android:text="取消"
        />
</RelativeLayout>

注册界面.java

public class RegisterActivity extends AppCompatActivity implements View.OnClickListener {
    private EditText et_username, et_password, et_repassword;
    private Button btn_cancel, btn_confirm;
    private int count;
    private long t;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);
        et_username = findViewById(R.id.et_username);
        et_password = findViewById(R.id.et_passsword);
        et_repassword = findViewById(R.id.et_repasssword);

        btn_cancel = findViewById(R.id.btn_cancel);
        btn_confirm = findViewById(R.id.btn_confirm);
        btn_cancel.setOnClickListener(this::onClick);
        btn_confirm.setOnClickListener(this::onClick);
        Intent intent = getIntent();
        String username = intent.getStringExtra("username");
        String password = intent.getStringExtra("password");

        et_username.setText(username);
        et_password.setText(password);
        et_repassword.setText(password);
        t = System.currentTimeMillis();
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btn_cancel:
                et_repassword.setText("");
                et_password.setText("");
                et_username.setText("");
                long t1 = System.currentTimeMillis();
                if (t1 - t < 2000) {
                    startActivity(new Intent(RegisterActivity.this, LoginActivity.class));
                }else {
                    t = System.currentTimeMillis();
                    Toast.makeText(RegisterActivity.this, "连续按两次回到登录界面", Toast.LENGTH_LONG).show();

                }
                break;
            case R.id.btn_confirm:
                if ((!"".equals(et_username.getText().toString())) && (!"".equals(et_password.getText().toString())) && (!"".equals(et_repassword.getText().toString()))) {
                    if (et_password.getText().toString().equals(et_repassword.getText().toString())) {
                        Toast.makeText(RegisterActivity.this, "注册成功", Toast.LENGTH_LONG).show();
                        Intent intent = new Intent(RegisterActivity.this, LoginActivity.class);
                        String dq_name = et_username.getText().toString();
                        String dq_password = et_password.getText().toString();
                        Bundle bundle = new Bundle();
                        bundle.putString("dq_name", dq_name);
                        bundle.putString("dq_password", dq_password);
                        intent.putExtras(bundle);
                        startActivity(intent);
                    } else {
                        Toast.makeText(RegisterActivity.this, "两次密码不一致", Toast.LENGTH_LONG).show();
                    }
                } else {
                    Toast.makeText(RegisterActivity.this, "不能为空", Toast.LENGTH_LONG).show();
                }
                break;
        }
    }