QR code读取相机 - 机器人

我目前正在研究建立在Android的闹钟应用程序。我完全，完全新的与QR codeS编程。我对它一无所知。但是现在，我想找出创建具有QR code功能的应用程序的可行性。 （我有两个星期建立这个）

I am currently researching to build an alarm clock application in Android. I am utterly and completely new to programming with QR codes. I know nothing about it. But right now, I want to find out the feasibility of creating an application with QR code functionality. (I have two weeks to build this)

我的第一个问题是：我会处理的相机自己在code也就是我必须启动它，然后将其关闭，然后再处理的QR图像

My first question is: would I have to handle the camera myself in the code i.e. do I have to fire it up and then close it and then process the QR image?

第二个问题：我如何创建QR code，然后当我扫描它，它是如何知道它扫描正确的？我想打印一个，将其放置在厨房或浴室，然后当警报响起时，我收到了警报关闭扫描code。

2nd Q: How would I create the QR code and then when I scan it, how does it know it scanned the right one? I want to print one, place it in the kitchen or bathroom and then when the alarm goes off, I have to scan the code before the alarm turns off.