android 自定义dialog中去除黑色背景 WindowManager

在服务中显示对话框，并且在退出软件后也可以出发对话框。

View v = View.inflate(mContext, R.layout.to_alarm_dialog_sub, null);
dialog = new Dialog(mContext, R.style.MyDialog);
AlertDialog.Builder b = new AlertDialog.Builder(mContext);
b.setView(v);
dialog = b.create();
dialog.getWindow()
.setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
dialog.show();
WindowManager.LayoutParams lp = dialog.getWindow().getAttributes();
WindowManager wm = (WindowManager) getSystemService(WINDOW_SERVICE);

这是一开始写的代码 ,但是这样写,黑色的背景还是会出现,

经过修改：

View v = View.inflate(mContext, R.layout.to_alarm_dialog_sub, null);
dialog = new Dialog(mContext, R.style.MyDialog);
dialog.getWindow()
.setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
dialog.setContentView(v);
dialog.show();
WindowManager.LayoutParams lp = dialog.getWindow().getAttributes();
WindowManager wm = (WindowManager) getSystemService(WINDOW_SERVICE);

这样就不会出现了