开发适用于Android 10的定制闹钟

开发适用于Android 10的定制闹钟可以使用Android Studio进行开发，下面是一个简单的示例代码：

首先，在AndroidManifest.xml文件中添加以下权限：

<uses-permission android:name="android.permission.SET_ALARM" />

然后，在MainActivity.java文件中添加以下代码：

import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TimePicker;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

import java.util.Calendar;

public class MainActivity extends AppCompatActivity {

    private TimePicker timePicker;
    private Button setAlarmButton;

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

        timePicker = findViewById(R.id.timePicker);
        setAlarmButton = findViewById(R.id.setAlarmButton);

        setAlarmButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int hour, minute;

                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                    hour = timePicker.getHour();
                    minute = timePicker.getMinute();
                } else {
                    hour = timePicker.getCurrentHour();
                    minute = timePicker.getCurrentMinute();
                }

                Calendar c = Calendar.getInstance();
                c.set(Calendar.HOUR_OF_DAY, hour);
                c.set(Calendar.MINUTE, minute);
                c.set(Calendar.SECOND, 0);

                setAlarm(c.getTimeInMillis());
            }
        });
    }

    private void setAlarm(long timeInMillis) {
        AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
        Intent intent = new Intent(this, AlarmReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent, 0);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            alarmManager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, timeInMillis, pendingIntent);
        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            alarmManager.setExact(AlarmManager.RTC_WAKEUP, timeInMillis, pendingIntent);
        } else {
            alarmManager.set(AlarmManager.RTC_WAKEUP, timeInMillis, pendingIntent);
        }

        Toast.makeText(this, "闹钟设置成功", Toast.LENGTH_SHORT).show();
    }
}

创建一个名为AlarmReceiver.java的广播接收器类：

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Build;
import android.widget.Toast;

public class AlarmReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        Toast.makeText(context, "闹钟响了！", Toast.LENGTH_LONG).show();
    }
}

最后，在activity_main.xml中添加以下布局：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:paddingLeft="16dp"
    android:paddingTop="16dp"
    android:paddingRight="16dp"
    android:paddingBottom="16dp"
    tools:context=".MainActivity">

    <TimePicker
        android:id="@+id/timePicker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:timePickerMode="spinner"
        android:layout_marginBottom="16dp" />

    <Button
        android:id="@+id/setAlarmButton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/timePicker"
        android:text="设置闹钟" />

</RelativeLayout>

以上代码示例演示了如何使用TimePicker选择时间，并通过AlarmManager设置闹钟。当闹钟时间到达时，将通过AlarmReceiver接收到广播，并显示一个Toast消息。

请注意，在Android 10及更高版本中，应用需要具有特定的权限才能设置闹钟，因此在AndroidManifest.xml文件中添加了"android.permission.SET_ALARM"权限。