1. Do not read Android development documents
The Android developer website can help you. Many documents can also be downloaded using SDK tools. These documents are not just a reference for the Javadoc API, but contain many guides, tutorials, videos, training, and other useful materials to create Android applications.
Android training guides you through some useful tutorial examples to solve specific problems or implement specific functions.
2. unfamiliar with Android development tools
Android SDK can be used not only to compile and package your applications to run on Android phones, but also has a complete set of tools to help you build applications. Some of these tools can help your application design graphics and layout. Other command line tools provide simple and Scriptable access to simulators and hardware devices. You can also tune and analyze the performance.
Android SDK documentation