Challenge:Saving State (slightly different)

Android Programming (3rd Edition) 31. Custom Views and Touch Events
1

Steps
1: Use this converter to implement Parcelable on Class Box or do it manually
[http://www.parcelabler.com/]

  1. Add 2 constants to class BoxDrawingView to track Parent and Child states

  2. Add id to fragment_drag_and_draw.xml

  3. In class BoxDrawingView add methods onSavedInstanceState and onRestoreInstanceState.

Differences: used putParcelableArrayList, getParcelableArrayList , readValues and writeValues

  1.     protected Box(Parcel in) {

     mOrigin = (PointF) in.readValue(PointF.class.getClassLoader());
     mCurrent = (PointF) in.readValue(PointF.class.getClassLoader());
 }

 @Override
 public int describeContents() {
     return 0;
 }

 @Override
 public void writeToParcel(Parcel dest, int flags) {
     dest.writeValue(mOrigin);
     dest.writeValue(mCurrent);
 }

 @SuppressWarnings("unused")
 public static final Parcelable.Creator<Box> CREATOR = new Parcelable.Creator<Box>() {
     @Override
     public Box createFromParcel(Parcel in) {
         return new Box(in);
     }

     @Override
     public Box[] newArray(int size) {
         return new Box[size];
     }
 };

  2.  private static final String PARENTVIEW_SAVED_STATE = "parentview";
 private static final String CHILDVIEW_SAVED_STATE = "childview";

  3. android:id="@+id/box_drawing_view"

  4.   @Override
 protected Parcelable onSaveInstanceState() {
     Parcelable viewState = super.onSaveInstanceState();
     Bundle bundle = new Bundle();
     bundle.putParcelable(PARENTVIEW_SAVED_STATE, viewState);
     bundle.putParcelableArrayList(CHILDVIEW_SAVED_STATE,( ArrayList<Box >) mBoxen);
     return bundle;
 }

 @Override
 protected void onRestoreInstanceState(Parcelable state) {
     Bundle bundle = (Bundle) state;
     super.onRestoreInstanceState(bundle.getParcelable(PARENTVIEW_SAVED_STATE));
     mBoxen =   bundle.getParcelableArrayList(CHILDVIEW_SAVED_STATE);

 }
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