2021/2/2

登录，进入之后选择登录或注册

package com.example.bookkeeping;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

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

    private void initUI() {
        findViewById(R.id.button1).setOnClickListener(this);
        findViewById(R.id.button2).setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.button1://执行按钮1
                Intent intent =new Intent();
                intent.setClass(getApplicationContext(), FirstActivity.class);
                this.startActivity(intent);
                break;
            case R.id.button2:
                Intent intent2 =new Intent();
                intent2.setClass(getApplicationContext(), secondActivity.class);
                this.startActivity(intent2);
                break;

        }

    }
}

一个onclick事件可以进行页面的跳转

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="46dp"
        android:text="用户名："
        android:textSize="30dp" />

    <EditText
        android:id="@+id/edit_1"
        android:layout_width="match_parent"
        android:layout_height="55dp"
        android:hint="请填写用户名"/>


    <TextView
        android:layout_width="wrap_content"
        android:layout_height="46dp"
        android:text="密码："
        android:textSize="30dp" />

    <EditText
        android:id="@+id/edit_2"
        android:layout_width="match_parent"
        android:layout_height="55dp"
        android:hint="请输入密码"/>


    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:text="登录" />

    <Button
        android:id="@+id/button2"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:text="注册" />

</LinearLayout>