                        课程
                    
                        /移动开发
                        
                            /Android
                        
                        /与Android Studio的第一次亲密接触

gradle project sync failed

老师：android studio版本1.1.0 JRE 版本1.8.0_25，提示gradle project sync failed,Basic functionality(e.g.diting. debugging)will not work properly.最下面提示Failed to find:com.android.support:appcompat-v7:21.+, Install Repository and sync project . show in File. show in project Structure dialog 请问如何解决，谢谢！