Android StudioでFlutterアプリを起動すると Could not find lint-gradle-api.jar (com.android.tools.lint:lint-gradle-api:26.1.2)

環境

• Android Studio 3.2.1
• Flutter 0.9.4

現象

Android StudioでFlutterアプリを新規作成して起動したところ Could not find lint-gradle-api.jar (com.android.tools.lint:lint-gradle-api:26.1.2) といったエラーが発生した

実行ログ

Launching lib/main.dart on Android SDK built for x86 in debug mode...
Initializing gradle...
Resolving dependencies...
* Error running Gradle:
Exit code 1 from: /Users/mouchi717/Projects/flutter_app_intro/android/gradlew app:properties:
Project evaluation failed including an error in afterEvaluate {}. Run with --stacktrace for details of the afterEvaluate {} error.

FAILURE: Build failed with an exception.

* Where:
Build file '/Users/mouchi717/Projects/flutter_app_intro/android/app/build.gradle' line: 26

* What went wrong:
A problem occurred evaluating project ':app'.
> Could not resolve all files for configuration 'classpath'.
   > Could not find lint-gradle-api.jar (com.android.tools.lint:lint-gradle-api:26.1.2).
     Searched in the following locations:
         https://jcenter.bintray.com/com/android/tools/lint/lint-gradle-api/26.1.2/lint-gradle-api-26.1.2.jar

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 3s

Finished with error: Please review your Gradle project setup in the android/ folder.

原因

Flutterのbuild.gradleにある依存関係の宣言順の問題。
公式のIssueでも既に解決されていた。
https://github.com/flutter/flutter/issues/23459

要するにjcenter()よりgoogle()を先に宣言する必要があるらしい。

解決方法

flutter.gradleの下記コードをjcenter()の上に移動するだけ。

maven {
    url 'https://dl.google.com/dl/android/maven2'
} 

修正後はこんな感じになる。

flutter/packages/flutter_tools/gradle/flutter.gradle

buildscript {
    repositories {
        maven {
            url 'https://dl.google.com/dl/android/maven2'
        }
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
    }
}

再度、起動してみるとうまくいった！

実行ログ

Launching lib/main.dart on Android SDK built for x86 in debug mode...
Initializing gradle...
Resolving dependencies...
timeout waiting for the application to start
Gradle task 'assembleDebug'...
Built build/app/outputs/apk/debug/app-debug.apk.
Installing build/app/outputs/apk/app.apk...
Syncing files to device Android SDK built for x86...
D/        ( 4302): HostConnection::get() New Host Connection established 0xdd6a9100, tid 4338
D/EGL_emulation( 4302): eglMakeCurrent: 0xcb9414e0: ver 3 0 (tinfo 0xcb94f240)
I/Choreographer( 4302): Skipped 44 frames!  The application may be doing too much work on its main thread.

実行結果