摘要：
Continue to type the following line of code: 接着之前代码写下：message2.lowercaseString + " Okay, i'm working on it"Swift allows you to concatenate two string... 阅读全文
摘要：
Use the default name or your own name but remember to select iOS as the platform. 使用默认的名字或者你自己的名字，但是切记要选择iOS平台Once you confirm to save the file, Xcod... 阅读全文
摘要：
Swift Playgrounds Swift操练场地In this year’s Worldwide Developer Conference, Apple surprised all iOS developers by launching a new programming language c... 阅读全文