Class not found

[dooreelko]

Android 4.22
Galaxy Tab2 10.1 (espress

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.meditationtracker2/com.meditationtracker2.SettingsActivity}: android.app.Fragment$InstantiationException: Unable to instantiate fragment com.meditationtracker2.SettingsActivity$GeneralPreferenceFragment: make sure class name exists, is public, and has an empty constructor that is public
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2295)
at android.app.ActivityThread.access$700(ActivityThread.java:150)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1280)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:175)
at android.app.ActivityThread.main(ActivityThread.java:5279)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.app.Fragment$InstantiationException: Unable to instantiate fragment com.meditationtracker2.SettingsActivity$GeneralPreferenceFragment: make sure class name exists, is public, and has an empty constructor that is public
at android.app.Fragment.instantiate(Fragment.java:596)
at android.preference.PreferenceActivity.switchToHeaderInner(PreferenceActivity.java:1245)
at android.preference.PreferenceActivity.switchToHeader(PreferenceActivity.java:1278)
at android.preference.PreferenceActivity.onCreate(PreferenceActivity.java:647)
at android.app.Activity.performCreate(Activity.java:5283)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1097)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2209)
... 11 more
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.meditationtracker2.SettingsActivity$GeneralPreferenceFragment" on path: /data/app/com.meditationtracker2-1.apk
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:65)
at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
at android.app.Fragment.instantiate(Fragment.java:582)