Since you are reading this post, I am guessing, you are probably familiar with Flutter. If not,
Flutter is Google’s mobile UI framework for crafting high-quality native interfaces on iOS and Android in record time. Flutter works with existing code, is used by developers and organizations around the world, and is free and open source.
"... in record time.", well I am sold! You can see it in action in this Google I/O '17 talk. Let's begin by setting it up.
Once you have cloned or downloaded the zip and extract it to the desired location. You will need to add
flutter tool to your $PATH.
$ export FLUTTER_HOME="$HOME/Developer/experimental/sdk/flutter" $ export PATH="$FLUTTER_HOME/bin:$PATH"
You would have the
flutter tool available now.
$ flutter --version
Flutter 0.2-pre • channel master • email@example.com:flutter/flutter.git Framework • revision a2951a9a1f (7 hours ago) • 2018-04-10 18:12:34 -0700 Engine • revision ed303c628f Tools • Dart 2.0-dev .flutter-23ae4fa098
You should see something like the above output. Now its time to install all dependencies of flutter.
flutter doctor -v should check and let you know about all the dependencies.
I get the following output from
flutter doctor -v.
[✗] Android toolchain - develop for Android devices ✗ ANDROID_HOME = /usr/local/share/android-sdk/ but Android SDK not found at this location.
I have installed
$ brew cask install android-sdk android-ndk
I have set the environment variables.
export ANDROID_SDK_ROOT="/usr/local/share/android-sdk/" export ANDROID_NDK_HOME="/usr/local/share/android-ndk/"
export ANDROID_HOME=$ANDROID_SDK_ROOT export PATH="$ANDROID_HOME""tools:$ANDROID_HOME""tools/bin:$ANDROID_HOME""platform-tools:$PATH"
sdkmanagerto install android dependencies
But this is not enough! It says it can't find the 'Android SDK' at the location. Time to install using
$ sdkmanager --list
Exception in thread "main" java.lang.NoClassDefFoundError: javax/xml/bind/annotation/XmlSchema at com.android.repository.api.SchemaModule$SchemaModuleVersion.<init>(SchemaModule.java:156) at com.android.repository.api.SchemaModule.<init>(SchemaModule.java:75) at com.android.sdklib.repository.AndroidSdkHandler.<clinit>(AndroidSdkHandler.java:81) at com.android.sdklib.tool.SdkManagerCli.main(SdkManagerCli.java:117) at com.android.sdklib.tool.SdkManagerCli.main(SdkManagerCli.java:93) Caused by: java.lang.ClassNotFoundException: javax.xml.bind.annotation.XmlSchema at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:190) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499) ... 5 more
Uh, oh! Looks like my java version is different than expected. Perhaps I am on Java 10. Using
$ jenv versions
system 1.8 188.8.131.52 * 10 (set by /private/tmp/.java-version) oracle64-184.108.40.206 oracle64-10
Let's switch to Java 1.8, restarting the shell and retrying...
$ jenv local 1.8 $ exec bash $ sdkmanager --list
... Installed packages: Path | Version | Description | Location ------- | ------- | ------- | ------- tools | 26.0.1 | Android SDK Tools 26.0.1 | tools/ done
Flutter doctor is still not happy. Perhaps we need to look more closely. Reading the
travis_setup.sh file in the repository, I can see that the
sdkmanager is used to install a bunch of stuff. Let's do the same locally.
$ sdkmanager "tools" $ sdkmanager "platform-tools" $ sdkmanager "build-tools;27.0.3" $ sdkmanager "platforms;android-27" $ sdkmanager "extras;android;m2repository" $ sdkmanager "extras;google;m2repository" $ sdkmanager "patcher;v4"
This seems to take care of almost everything.
$ flutter doctor -v
[!] Android toolchain - develop for Android devices (Android SDK 27.0.3) • Android SDK at /usr/local/share/android-sdk/ • Android NDK location not configured (optional; useful for native profiling support) • Platform android-27, build-tools 27.0.3 • ANDROID_HOME = /usr/local/share/android-sdk/ • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01) ! Some Android licenses not accepted. To resolve this, run: flutter doctor --android-licenses
One last thing, I suppose:
$ flutter doctor --android-licenses
I get the following output from
flutter doctor -v.
[✓] iOS toolchain - develop for iOS devices (Xcode 9.3) • Xcode at /Applications/Xcode.app/Contents/Developer • Xcode 9.3, Build version 9E145 • ios-deploy 1.9.2 • CocoaPods version 1.5.0
All my dependencies for iOS are in place. Well I am an iOS developer after all.
I generally prefer installing
bundler. I have my
source "https://rubygems.org" gem 'cocoapods'
bundle install. After that
pod setup should do the trick.
After installing Xcode, install the 'Command Line Tools' using
Install the xcode dependency
six, as reported by the
$ pip install six
$ brew install --HEAD libimobiledevice $ brew install ideviceinstaller ios-deploy
Flutter works best with 'Android Studio'. It also detects 'IntelliJ Idea' and 'Visual Studio Code'. You will need to install the appropriate plugins.
Connect your iOS or Android device to your machine over USB. That should take care of itself.
flutter doctor is happy now. And you can begin writing your first application (
flutter create) in Dart or run from the examples directory.
$ cd examples/flutter_gallery/ $ flutter run
For iOS, you will need to configure the development team by opening Xcode workspace in
As always, please leave your comments and feedback in the comment section below. I hope you found this post useful. Happy developing.