1、Warning:The android.dexOptions.incremental property is deprecated and it has no effect on the build process.
该警告的意思是指’android.dexOptions.incremental’这个property已经过时了，所以解决方法就很明显了，直接去掉gradle下的

dexOptions {
        incremental true
    }

2、Error:Failed to resolve:
com.android.support:support-annotations:27.0.1
Install Repository and sync project
Open File
Show in Project Structure dialog
这个错误的话应该是Android Studio插件版本问题，解决的办法为，在gradle的buildtypes里面加入repositories { maven { url “https://maven.google.com” }}，具体如下：

buildTypes {
   repositories {
      maven {
            url "https://maven.google.com"
            }
        }
      release {
            minifyEnabled false
            proguardFiles   
            getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }