Proguard & Retrofit 错误

Question

我想在我的项目中使用 ProGuard。我激活了 minifyEnabled 选项。当我打开使用库 Retrofit2 的活动时，应用程序崩溃并显示此错误：

无法为接口 retrofit2.Call 创建调用适配器

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.gatafan.mydeen/com.gatafan.mydeen.ActivityPlaces}:
        java.lang.IllegalArgumentException: Unable to create call adapter for interface retrofit2.Call
for method i.a
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2338)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
at android.os.Handler.dispatchMessage(Handler.java:110)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:5292)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.IllegalArgumentException: Unable to create call adapter for interface retrofit2.Call
for method i.a
at retrofit2.ServiceMethod$Builder.a(Unknown Source)
at retrofit2.ServiceMethod$Builder.b(Unknown Source)
at retrofit2.ServiceMethod$Builder.a(Unknown Source)
at retrofit2.Retrofit.a(Unknown Source)
at retrofit2.Retrofit$1.invoke(Unknown Source)
at com.gatafan.mydeen.api.$Proxy1.a(Native Method)
at com.gatafan.mydeen.api.VenueManager.requestFoursquare(Unknown Source)
at com.gatafan.mydeen.ActivityPlaces.onCreate(Unknown Source)
at android.app.Activity.performCreate(Activity.java:5264)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1088)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2302)
... 11 more
Caused by: java.lang.IllegalArgumentException: Call return type must be parameterized as Call<Foo> or Call<? extends Foo>
        at retrofit2.Utils.e(Unknown Source)
at retrofit2.ExecutorCallAdapterFactory.a(Unknown Source)
at retrofit2.Retrofit.a(Unknown Source)
at retrofit2.Retrofit.a(Unknown Source)
... 21 more

Answer 1

在 Retrofit 的 github 页面中，有一节解释了使用 proguard 时的操作：

PROGUARD 如果您在项目中使用 Proguard，则将以下行添加到您的配置中：

-dontwarn retrofit2.**
-keep class retrofit2.** { *; }
-keepattributes Signature
-keepattributes Exceptions

先尝试此配置，然后再继续进行 proguard 更改