【练习】登录界面

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    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="请输入用户名"/>
    <EditText
        android:id="@+id/password"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="请输入密码"/>
    <RadioGroup
        android:id="@+id/sex"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_gravity="center_horizontal">

        <RadioButton
            android:id="@+id/man"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:checked="true"
            android:text="男生"
            android:layout_marginRight="50dp"/>

        <RadioButton
            android:id="@+id/woman"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="女生"/>
    </RadioGroup>
    <LinearLayout
        android:id="@+id/birthDate"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:orientation="horizontal"
        android:gravity="center_horizontal">
        <EditText
            android:id="@+id/birth_year"
            android:layout_width="80dp"
            android:layout_height="wrap_content" />
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="年"/>
        <Spinner
            android:id="@+id/birth_month"
            android:layout_width="30dp"
            android:layout_height="wrap_content"></Spinner>
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="月"/>
        <Spinner
            android:id="@+id/birth_day"
            android:layout_width="30dp"
            android:layout_height="wrap_content"></Spinner>
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="日"/>
    </LinearLayout>
    <LinearLayout
        android:id="@+id/loveBall"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:gravity="center_horizontal">
        <CheckBox
            android:id="@+id/basketball"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="篮球"/>
        <CheckBox
            android:id="@+id/football"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="足球"/>
        <CheckBox
            android:id="@+id/pingpang"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="乒乓球"/>
    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center_horizontal">
        <Button
            android:id="@+id/login"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="login"
            android:text="登录"/>
        <Button
            android:id="@+id/reset"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="reset"
            android:text="重置"/>
    </LinearLayout>
</LinearLayout>

public class MainActivity extends AppCompatActivity {

    private TextView textView_userName, textView_password, textview_birthyear;
    private RadioGroup radioGroup_sex;
    private Spinner spinner_month;
    private Spinner spinner_day;
    private CheckBox[] checkbox_loveball;
    private RadioButton radioButton_man, radioButton_woman;
    private CheckBox checkBox_basketball, checkBox_football, checkBox_pingpang;

    private String userName, password, sex, birth_year, birth_month, birth_day, love_ball;
    private List<String> birthMonth_list;
    private List<String> birthDay_list;

    private ArrayAdapter<String> month_adapter;
    private ArrayAdapter<String> day_adapter;

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

    }

    //初始化页面
    private void initView() {
        textView_userName = (TextView) findViewById(R.id.userName);
        textView_password = (TextView) findViewById(R.id.password);
        radioGroup_sex = (RadioGroup) findViewById(R.id.sex);
        radioButton_man = (RadioButton) findViewById(R.id.man);
        radioButton_woman = (RadioButton) findViewById(R.id.woman);
        checkBox_basketball = (CheckBox) findViewById(R.id.basketball);
        checkBox_football = (CheckBox) findViewById(R.id.football);
        checkBox_pingpang = (CheckBox) findViewById(R.id.pingpang);

        textview_birthyear = (TextView) findViewById(R.id.birth_year);
        //初始化月
        spinner_month = (Spinner) findViewById(R.id.birth_month);
        birthMonth_list = new ArrayList<String>();
        for (int i = 1; i <= 12; i++) {
            birthMonth_list.add(i + "");
        }
        month_adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, birthMonth_list);
        spinner_month.setAdapter(month_adapter);
        spinner_month.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                birth_month = ((TextView) view).getText().toString();
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
        //初始化日
        spinner_day = (Spinner) findViewById(R.id.birth_day);
        birthDay_list = new ArrayList<String>();
        for (int i = 0; i <= 31; i++) {
            birthDay_list.add(i + "");
        }
        day_adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, birthDay_list);
        spinner_day.setAdapter(day_adapter);
        spinner_day.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                birth_day = ((TextView) view).getText().toString();
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
        //初始化多选框
        checkbox_loveball = new CheckBox[3];
        checkbox_loveball[0] = (CheckBox) findViewById(R.id.basketball);
        checkbox_loveball[1] = (CheckBox) findViewById(R.id.football);
        checkbox_loveball[2] = (CheckBox) findViewById(R.id.pingpang);

    }

    //登录
    public void login(View view) {
        userName = textView_userName.getText().toString();
        password = textView_password.getText().toString();
        for (int i = 0; i < radioGroup_sex.getChildCount(); i++) {
            RadioButton rb = (RadioButton) radioGroup_sex.getChildAt(i);
            if (rb.isChecked()) {
                sex = rb.getText().toString();
            }
        }
        birth_year = textview_birthyear.getText().toString();

        love_ball = "";
        for (int i = 0; i < checkbox_loveball.length; i++) {
            if (checkbox_loveball[i].isChecked()) {
                love_ball += checkbox_loveball[i].getText().toString() + " ";
            }
        }
        if ("admin".equals(userName) && "123456".equals(password)) {
            Toast.makeText(this, "登录成功" + "\n用户名：" + userName + "\n密码:" + password + "\n性别:" + sex + "\n出生日期：" +
                    birth_year + "年" + birth_month + "月" + birth_day + "日" + "\n爱好:" + love_ball, Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "登录失败", Toast.LENGTH_SHORT).show();
        }
    }

    //重置
    public void reset(View view) {
        textView_userName.setText("");
        textView_password.setText("");
        textview_birthyear.setText("");
        radioButton_man.setChecked(true);
        radioButton_woman.setChecked(false);
        checkBox_basketball.setChecked(false);
        checkBox_football.setChecked(false);
        checkBox_pingpang.setChecked(false);
    }
}