https://youkmi.blog.csdn.net/article/details/108728322?spm=1001.2101.3001.6661.1&utm_medium=distribute.pc_relevant_t0.none-task-blog-2%7Edefault%7ECTRLIST%7EPayColumn-1.pc_relevant_paycolumn_v3&depth_1-utm_source=distribute.pc_relevant_t0.none-task-blog-2%7Edefault%7ECTRLIST%7EPayColumn-1.pc_relevant_paycolumn_v3&utm_relevant_index=1 可空声明 类型？变量名称 与kotlin一样 非空断言 变量名称！ kotlin是2个！！ 初始化非空变量 required 关键字 或者参数加默认值， late final关键字也一样
chmod 777 ./gradlew
https://docs.flutter.dev/development/add-to-app/android/project-setup#add-the-flutter-module-as-a-dependency option 1: 打包flutter工程为aar倒入已有工程（方便没有dart-sdk的开发） Option A – Depend on the Android Archive (AAR) This option packages your Flutter library as a generic local Maven repository composed of AARs and POMs artifacts. This option allows your team to build the host app without installing the Flutter SDK. You can then distribute the artifacts from a local …