flutter note

project types

application

a whole new application

plugin

exposing an android or ios api for developers

package

creating a pure dart component, like a new widget

module

creating a flutter component to add to an android app

commonly used commands

• Upgrade
  $ flutter upgrade

• switch channel (stable recommended)
  $ fultter channel beta/dev/master/stable

• check environment
  $ flutter doctor

flutter for web (in progress)

for details, check article

flutter for desktop

by google

by a 3rd party company, commercial license, check article

problem notes

debug app with blank screen

One possible reason is your environment variable http_proxy/https_proxy has block the communication between flutter compiler and flutter vm on the remote device. If this is the case, we just set an environment variable no_proxy with 127.0.0.1 included to solve this problem.

Memo

Releationships between Widget, Element and RenderObject

[todo] - refer to

Cocoapods

You can install Cocoapods via two ways: homebrew and rubygems

by homebrew

$ brew install cocoapods

by rubygems

$ sudo gem install cocoapods

for details, refer to

rubygems

replace source with chinese mirror

$ gem sources --add https://gems.ruby-china.com/ --remove https://rubygems.org/
$ gem sources -l

Json and Serialization

• For small project - decode manually
  • or, you can use the following online tool to help you generate the serialization logic
• For medium to large projects - code generation
  • • add a dev dependency - build_runner: ^1.0.0
    • one-time code generation - $ flutter pub run build_runner build
    • generating code continuously - $ flutter pub run build_runner watch
    • this lib will generate a new file named xxx.g.dart with all generated utility functions, however, you’ll need to write the below boilerplate functions
      • factory XXX.fromJson(Map<String, dynamic> json) => _$XXXFromJson(json);
      • Map<String, dynamic> toJson() => _$XXXToJson(this);
• Flutter does not support runtime reflection, that is why you cannot find a GSON/Jackson/Moshi equivalent in flutter.
  • Runtime reflection interferes with tree shaking. With tree shaking, you can “shake off” unused code from your release builds. This optimizes the app’s size significantly.

For details, refer to

Hot restart/reload and debugging dart code for flutter module

Execute the following command under flutter module root directory,

$ flutter attach

Then, launch your application in debug mode from Android Studio or Xcode.

it seems there’s a problem in attaching a ios emulator, refer to
resolved in new version (1.7.8+hotfix.3)

References

study resources