Android Kotlin全屏通知异常：锁屏/关机时无法弹出全屏界面

你遇到的核心问题是全屏Intent传错了对象，再加上缺少锁屏显示的必要配置，导致无法像原生闹钟那样弹出全屏页面。下面是具体修正步骤：

1. 修正AlarmReceiver中的全屏Intent参数 #

你在NotificationCompat.Builder里调用setFullScreenIntent()时，错误传入了对应广播的pendingIntent，而非指向AlarmPage的fullScreenPendingIntent。修改后的代码：

class AlarmReceiver : BroadcastReceiver() {
    val notificationId = 2
    val channelID = "androidAlarm4"

    override fun onReceive(context: Context?, intent: Intent?) {
        context ?: return

        // 正确创建指向全屏页面的PendingIntent
        val fullScreenIntent = Intent(context, AlarmPage::class.java)
        val fullScreenPendingIntent = PendingIntent.getActivity(
            context,
            1001, // 用唯一requestCode避免冲突
            fullScreenIntent,
            PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT
        )

        val sound = Uri.parse("android.resource://${context.packageName}/${R.raw.siren}")
        val notification = NotificationCompat.Builder(context, channelID)
            .setSmallIcon(R.drawable.notification_bg)
            .setContentTitle("Reminder ALARM")
            .setContentText("Work has to be done now!!")
            .setPriority(NotificationCompat.PRIORITY_HIGH)
            .setSound(
                sound,
                AudioAttributes.Builder().setUsage(AudioAttributes.USAGE_ALARM).build()
            )
            .setAutoCancel(true)
            .setCategory(NotificationCompat.CATEGORY_ALARM)
            .setFullScreenIntent(fullScreenPendingIntent, true) // 这里传入正确的PendingIntent
            .build()

        val notificationManager = context.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        notificationManager.notify(notificationId, notification)
    }
}

2. 配置AlarmPage的Manifest属性 #

要让页面在锁屏/黑屏状态下显示，必须在AndroidManifest.xml中给AlarmPage添加以下属性：

<activity
    android:name=".AlarmPage"
    android:showOnLockScreen="true"
    android:showWhenLocked="true"
    android:turnScreenOn="true"
    android:excludeFromRecents="true"
    android:launchMode="singleInstance" />

3. 完善AlarmPage的唤醒与解锁逻辑 #

在AlarmPage的onCreate方法中添加代码，确保屏幕被唤醒并能在锁屏状态下交互：

class AlarmPage : AppCompatActivity() {
    private lateinit var stopReminder : Button

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        
        // Android 7.1+ 强制显示在锁屏上并唤醒屏幕
        setShowWhenLocked(true)
        setTurnScreenOn(true)
        
        // Android 10+ 请求解锁屏幕（可选）
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
            val keyguardManager = getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
            keyguardManager.requestDismissKeyguard(this, null)
        }
        
        setContentView(R.layout.activity_alarm_page)
        init()

        stopReminder.setOnClickListener {
            // 关闭通知并结束当前页面
            val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
            notificationManager.cancel(2)
            finish()
        }
    }

    private fun init(){
        stopReminder = findViewById(R.id.stopReminder)
    }
}

4. 补充必要权限 #

在AndroidManifest.xml中添加权限，确保闹钟不受电池优化影响且能发送通知：

<!-- Android 13+ 通知权限 -->
<uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
<!-- 忽略电池优化，避免闹钟被系统杀死 -->
<uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
<!-- 唤醒屏幕权限 -->
<uses-permission android:name="android.permission.WAKE_LOCK" />

在设置闹钟前，请求忽略电池优化（AddActivity的setAlarm方法开头添加）：

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    val powerManager = getSystemService(Context.POWER_SERVICE) as PowerManager
    if (!powerManager.isIgnoringBatteryOptimizations(packageName)) {
        val intent = Intent(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS)
        intent.data = Uri.parse("package:$packageName")
        startActivity(intent)
    }
}

额外注意事项 #

• 测试时用真机：部分模拟器对全屏Intent的支持存在问题
• 确保notification_bg是符合系统要求的纯色小图标，否则通知可能无法正常显示
• 闹钟的PendingIntent随机requestCode可能导致重复覆盖，建议用每个闹钟的唯一ID作为requestCode

内容的提问来源于stack exchange，提问作者Haitham Shalabi