at least with O, we no longer can rely on superstate being empty. Imp…

…lement proper parceling of both super and wrapped state

library/src/se/emilsjolander/stickylistheaders/StickyListHeadersListView.java

@@ -8,6 +8,7 @@
 import android.graphics.Canvas;
 import android.graphics.drawable.Drawable;
 import android.os.Build;
+import android.os.Parcel;
 import android.os.Parcelable;
 import android.util.AttributeSet;
 import android.util.Log;
@@ -1121,17 +1122,14 @@ public void setMultiChoiceModeListener(MultiChoiceModeListener listener) {
 
     @Override
     public Parcelable onSaveInstanceState() {
-        Parcelable superState = super.onSaveInstanceState();
-        if (superState != BaseSavedState.EMPTY_STATE) {
-          throw new IllegalStateException("Handling non empty state of parent class is not implemented");
-        }
-        return mList.onSaveInstanceState();
+        return new SavedState(super.onSaveInstanceState(), mList.onSaveInstanceState());
     }
 
     @Override
     public void onRestoreInstanceState(Parcelable state) {
-        super.onRestoreInstanceState(BaseSavedState.EMPTY_STATE);
-        mList.onRestoreInstanceState(state);
+        SavedState ss = (SavedState) state;
+        super.onRestoreInstanceState(ss.getSuperState());
+        mList.onRestoreInstanceState(ss.wrappedState);
     }
 
     @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
@@ -1155,4 +1153,41 @@ public void setStackFromBottom(boolean stackFromBottom) {
     public boolean isStackFromBottom() {
     	return mList.isStackFromBottom();
     }
+
+    static class SavedState extends BaseSavedState {
+        private Parcelable wrappedState;
+
+        /**
+         * Constructor called from {@link StickyListHeadersListView#onSaveInstanceState()}
+         */
+        SavedState(Parcelable superState, Parcelable wrappedState) {
+            super(superState);
+            this.wrappedState = wrappedState;
+        }
+
+        /**
+         * Constructor called from {@link #CREATOR}
+         */
+        private SavedState(Parcel in) {
+            super(in);
+            wrappedState = in.readParcelable(null);
+        }
+
+        @Override
+        public void writeToParcel(Parcel out, int flags) {
+            super.writeToParcel(out, flags);
+            out.writeValue(wrappedState);
+        }
+
+        public static final Parcelable.Creator<SavedState> CREATOR
+            = new Parcelable.Creator<SavedState>() {
+            public SavedState createFromParcel(Parcel in) {
+                return new SavedState(in);
+            }
+
+            public SavedState[] newArray(int size) {
+                return new SavedState[size];
+            }
+        };
+    }
 }