增删改查

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.login1">

<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".secondActivity"/>
</application>

</manifest>
package com.example.login1;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.os.Parcelable;
import android.view.View;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;

import com.example.login1.R;

public class MainActivity extends AppCompatActivity implements CompoundButton.OnCheckedChangeListener {

private String hobbys;
final Intent intent = new Intent();
private EditText name;
private EditText password;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
name = (EditText)findViewById(R.id.etname);
password = (EditText)findViewById(R.id.etpass);
RadioGroup rg = (RadioGroup)findViewById(R.id.rg);
CheckBox print = (CheckBox)findViewById(R.id.print);
CheckBox basketball = (CheckBox)findViewById(R.id.basketball);
CheckBox sing = (CheckBox)findViewById(R.id.sing);
CheckBox dance = (CheckBox)findViewById(R.id.dance);
hobbys