如何在Android应用中实现每日轮播字符串数组内容

<!-- res/values/strings.xml -->
<resources>
    <string-array name="daily_greetings">
        <item>早上好！愿你今天充满活力。</item>
        <item>新的一天，新的开始！</item>
        <item>祝你度过美好的一天！</item>
        <item>早安，生活因你而精彩。</item>
        <item>今天也要加油哦！</item>
    </string-array>
</resources>

import android.content.res.Resources;

// ...
String[] dailyGreetingsArray;

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

    Resources res = getResources();
    dailyGreetingsArray = res.getStringArray(R.array.daily_greetings);
    // ... 其他初始化代码
}

import android.content.SharedPreferences;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;

public class MainActivity extends AppCompatActivity {

    private static final String PREFS_NAME = "DailyMessagePrefs";
    private static final String KEY_LAST_UPDATE_DATE = "lastUpdateDate";
    private static final String KEY_CURRENT_MESSAGE_INDEX = "currentMessageIndex";

    private String[] dailyGreetingsArray;
    private SharedPreferences sharedPreferences;
    private TextView dailyMessageTextView; // 假设你有一个TextView来显示消息

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

        dailyMessageTextView = findViewById(R.id.dailyMessageTextView); // 你的TextView ID

        Resources res = getResources();
        dailyGreetingsArray = res.getStringArray(R.array.daily_greetings);
        sharedPreferences = getSharedPreferences(PREFS_NAME, MODE_PRIVATE);

        displayDailyMessage();
    }

    private void displayDailyMessage() {
        // 获取当前日期
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd", Locale.getDefault());
        String todayDate = dateFormat.format(new Date());

        // 从SharedPreferences获取上次更新日期和当前索引
        String lastUpdateDate = sharedPreferences.getString(KEY_LAST_UPDATE_DATE, "");
        int currentMessageIndex = sharedPreferences.getInt(KEY_CURRENT_MESSAGE_INDEX, 0);

        // 检查是否是新的一天
        if (!todayDate.equals(lastUpdateDate)) {
            // 新的一天，更新消息
            // 方式一：按顺序轮播 (循环到数组末尾后回到开头)
            int nextIndex = (currentMessageIndex + 1) % dailyGreetingsArray.length;

            // 方式二：随机选择 (如果需要随机，则使用此行代替上一行)
            // int nextIndex = new Random().nextInt(dailyGreetingsArray.length);

            String messageToShow = dailyGreetingsArray[nextIndex];
            dailyMessageTextView.setText(messageToShow);

            // 保存新的日期和索引
            SharedPreferences.Editor editor = sharedPreferences.edit();
            editor.putString(KEY_LAST_UPDATE_DATE, todayDate);
            editor.putInt(KEY_CURRENT_MESSAGE_INDEX, nextIndex);
            editor.apply(); // 使用apply()异步保存，提高性能
        } else {
            // 仍然是同一天，显示之前保存的消息
            String messageToShow = dailyGreetingsArray[currentMessageIndex];
            dailyMessageTextView.setText(messageToShow);
        }
    }
}

<!-- activity_main.xml -->
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:gravity="center">

    <TextView
        android:id="@+id/dailyMessageTextView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="每日问候语将显示在这里"
        android:textSize="20sp"
        android:padding="16dp" />

</LinearLayout>