Android 8.0如何完美适配全局dialog悬浮窗弹出

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

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

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
  if (Settings.canDrawOverlays(MainActivity.this)) {
   Intent intent = new Intent(MainActivity.this, MainService.class);
   startService(intent);
   finish();
  } else {
   //若没有权限，提示获取.
   Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION);
   Toast.makeText(MainActivity.this,"需要取得权限以使用悬浮窗",Toast.LENGTH_SHORT).show();
   startActivity(intent);
  }
  
}else {
 //SDK在23以下，不用管.
 Intent intent = new Intent(MainActivity.this, MainService.class);
 startService(intent);
 finish();
}

 //8.0系统加强后台管理，禁止在其他应用和窗口弹提醒弹窗，如果要弹，必须使用TYPE_APPLICATION_OVERLAY
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
 dialog.getWindow().setType((WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY));
}else {
 dialog.getWindow().setType((WindowManager.LayoutParams.TYPE_SYSTEM_ALERT));
}
dialog.show();