InstantiationException in HomeActivity

[mwfarb]

FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{edu.cmu.cylab.starslinger/edu.cmu.cylab.starslinger.view.HomeActivity}: android.support.v4.app.Fragment$InstantiationException: Unable to instantiate fragment edu.cmu.cylab.starslinger.view.MessagesFragment$MessagesAlertDialogFragment: make sure class name exists, is public, and has an empty constructor that is public
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3692)
at android.app.ActivityThread.access$700(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1240)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5041)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.support.v4.app.Fragment$InstantiationException: Unable to instantiate fragment edu.cmu.cylab.starslinger.view.MessagesFragment$MessagesAlertDialogFragment: make sure class name exists, is public, and has an empty constructor that is public
at android.support.v4.app.Fragment.instantiate(Fragment.java:431)
at android.support.v4.app.FragmentState.instantiate(Fragment.java:101)
at android.support.v4.app.FragmentManagerImpl.restoreAllState(FragmentManager.java:1823)
at android.support.v4.app.FragmentActivity.onCreate(FragmentActivity.java:264)
at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:97)
at edu.cmu.cylab.starslinger.view.HomeActivity.onCreate(HomeActivity.java:475)
at android.app.Activity.performCreate(Activity.java:5104)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
... 12 more
Caused by: java.lang.InstantiationException: can't instantiate class edu.cmu.cylab.starslinger.view.MessagesFragment$MessagesAlertDialogFragment; no empty constructor
at java.lang.Class.newInstanceImpl(Native Method)
at java.lang.Class.newInstance(Class.java:1319)
at android.support.v4.app.Fragment.instantiate(Fragment.java:420)
... 20 more