当AndroidManifest.xml请求权限时，它将返回isGranted = true。

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

实际上，意图是Settings.ACTION_REQUEST_SCHEDULE_EXACT_ALARM：

ActivityResultLauncher<Intent> startActivityForResult = registerForActivityResult(
        new ActivityResultContracts.StartActivityForResult(), (ActivityResult result) -> {
            if (result.getResultCode() == RESULT_OK) {}
        });

@RequiresApi(api = Build.VERSION_CODES.S_V2)
void hasPermission(@NonNull Context context) {
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S_V2) {

        // it depends on the manifest permission, just alike the toggle does.
        if (! alarmManager.canScheduleExactAlarms()) {

        }

        // one can only disable the permission, when the manifest requested it.
        startActivityForResult.launch(new Intent(
                Settings.ACTION_REQUEST_SCHEDULE_EXACT_ALARM,
                Uri.parse("package:" + getPackageName())
        ));
    }
}

监听广播操作AlarmManager.ACTION_SCHEDULE_EXACT_ALARM_PERMISSION_STATE_CHANGED。
此外，还有权限USE_EXACT_ALARM，目标是API 33。
参见行为变化：准确的警报许可。