Migrate example app to Kotlin

.travis.yml

@@ -23,5 +23,5 @@ before_install:
   - yes | sdkmanager "platforms;android-28"
 
 script:
-  - ./gradlew :stripe:checkstyle :example:checkstyle :samplestore:checkstyle :samplestore:ktlint lint
+  - ./gradlew :stripe:checkstyle :example:checkstyle :samplestore:checkstyle :example:ktlint :samplestore:ktlint lint
   - ./gradlew clean test

example/AndroidManifest.xml

@@ -37,8 +37,7 @@
             android:exported="false"/>
 
         <activity
-            android:name=".activity.RedirectActivity"
-            android:launchMode="singleTask">
+            android:name=".activity.RedirectActivity">
             <intent-filter>
                 <action android:name="android.intent.action.VIEW"/>
 
@@ -61,8 +60,7 @@
             </intent-filter>
         </activity>
         <activity
-            android:name=".activity.LauncherActivity"
-            android:launchMode="singleTask">
+            android:name=".activity.LauncherActivity">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
 
@@ -97,7 +95,7 @@
             android:name=".activity.PaymentAuthActivity" />
 
         <activity
-            android:name=".activity.FragmentExampesActivity" />
+            android:name=".activity.FragmentExamplesActivity" />
     </application>
 
 </manifest>

example/build.gradle

@@ -1,8 +1,14 @@
 apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'
 apply plugin: 'checkstyle'
 assemble.dependsOn('lint')
 check.dependsOn('checkstyle')
 
+configurations {
+    ktlint
+}
+
 dependencies {
     implementation project(':stripe')
     implementation 'com.android.support:multidex:1.0.3'
@@ -39,6 +45,8 @@ dependencies {
     releaseImplementation 'com.squareup.leakcanary:leakcanary-android-no-op:1.6.3'
     // Optional, if you use support library fragments:
     debugImplementation 'com.squareup.leakcanary:leakcanary-support-fragment:1.6.3'
+
+    ktlint "com.pinterest:ktlint:0.33.0"
 }
 
 android {
@@ -85,3 +93,22 @@ android {
         }
     }
 }
+
+task ktlint(type: JavaExec, group: "verification") {
+    description = "Check Kotlin code style."
+    main = "com.pinterest.ktlint.Main"
+    classpath = configurations.ktlint
+    args "src/**/*.kt"
+    // to generate report in checkstyle format prepend following args:
+    // "--reporter=plain", "--reporter=checkstyle,output=${buildDir}/ktlint.xml"
+    // see https://github.com/pinterest/ktlint#usage for more
+}
+check.dependsOn ktlint
+
+task ktlintFormat(type: JavaExec, group: "formatting") {
+    description = "Fix Kotlin code style deviations."
+    main = "com.pinterest.ktlint.Main"
+    classpath = configurations.ktlint
+    args "-F", "src/**/*.kt"
+}
+

example/src/main/java/com/stripe/example/ExampleApplication.kt

@@ -0,0 +1,33 @@
+package com.stripe.example
+
+import android.os.StrictMode
+import android.support.multidex.MultiDexApplication
+
+import com.facebook.stetho.Stetho
+import com.squareup.leakcanary.LeakCanary
+
+class ExampleApplication : MultiDexApplication() {
+
+    override fun onCreate() {
+        super.onCreate()
+
+        StrictMode.setVmPolicy(StrictMode.VmPolicy.Builder()
+            .detectLeakedSqlLiteObjects()
+            .detectLeakedClosableObjects()
+            .penaltyLog()
+            .penaltyDeath()
+            .build())
+
+        Stetho.initializeWithDefaults(this)
+
+        if (BuildConfig.DEBUG && LeakCanary.isInAnalyzerProcess(this)) {
+            // This process is dedicated to LeakCanary for heap analysis.
+            // You should not init your app in this process.
+            return
+        }
+
+        if (BuildConfig.DEBUG) {
+            LeakCanary.install(this)
+        }
+    }
+}

example/src/main/java/com/stripe/example/Settings.kt

@@ -0,0 +1,26 @@
+package com.stripe.example
+
+/**
+ * See [Configuring the example app](https://github.com/stripe/stripe-android#building-the-example-project)
+ * for instructions on how to configure the app before running it.
+ */
+internal object Settings {
+    /**
+     * Set to the base URL of your test backend. If you are using
+     * [example-ios-backend](https://github.com/stripe/example-ios-backend),
+     * the URL will be something like `https://hidden-beach-12345.herokuapp.com/`.
+     */
+    const val BASE_URL = "put your base url here"
+
+    /**
+     * Set to publishable key from https://dashboard.stripe.com/test/apikeys
+     */
+    const val PUBLISHABLE_KEY = "pk_test_your_key_goes_here"
+
+    /**
+     * Optionally, set to a Connect Account id to use for API requests to test Connect
+     *
+     * See https://dashboard.stripe.com/test/connect/accounts/overview
+     */
+    val STRIPE_ACCOUNT_ID: String? = null
+}