我有以下错误：
12-03 12:20:08.270 28282-28312/com.topantidevelopers.goloud E/Fabric﹕ Unknown error while loading Crashlytics settings. Crashes will be cached until settings can be retrieved.
java.lang.NullPointerException: Attempt to invoke interface method 'void com.android.okhttp.internal.http.Transport.writeRequestHeaders(com.android.okhttp.Request)' on a null object reference
at com.android.okhttp.internal.http.HttpEngine.readResponse(HttpEngine.java:599)
at com.android.okhttp.internal.http.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:379)
at com.android.okhttp.internal.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:323)
at com.android.okhttp.internal.http.HttpURLConnectionImpl.getHeaderField(HttpURLConnectionImpl.java:152)
at com.android.okhttp.internal.http.DelegatingHttpsURLConnection.getHeaderField(DelegatingHttpsURLConnection.java:190)
at com.android.okhttp.internal.http.HttpsURLConnectionImpl.getHeaderField(HttpsURLConnectionImpl.java:25)
at io.fabric.sdk.android.services.network.HttpRequest.header(HttpRequest.java:1875)
at io.fabric.sdk.android.services.settings.DefaultSettingsSpiCall.invoke(DefaultSettingsSpiCall.java:93)
at io.fabric.sdk.android.services.settings.DefaultSettingsController.loadSettingsData(DefaultSettingsController.java:80)
at io.fabric.sdk.android.services.settings.DefaultSettingsController.loadSettingsData(DefaultSettingsController.java:64)
在导入库时也出现了此消息：
io-fabric-sdk-android_fabric] Using 1.7 requires compiling with Android 4.4 (KitKat); Currently using API 10
也许是它的版本。
有人可以帮助我吗？