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    <p>You do this by implementing <a href="http://developer.android.com/reference/android/view/View.html#onSaveInstanceState%28%29" rel="noreferrer"><code>View#onSaveInstanceState</code></a> and <a href="http://developer.android.com/reference/android/view/View.html#onRestoreInstanceState%28android.os.Parcelable%29" rel="noreferrer"><code>View#onRestoreInstanceState</code></a> and extending the <a href="http://developer.android.com/reference/android/view/View.BaseSavedState.html" rel="noreferrer"><code>View.BaseSavedState</code></a> class.</p> <pre><code>public class CustomView extends View { private int stateToSave; ... @Override public Parcelable onSaveInstanceState() { //begin boilerplate code that allows parent classes to save state Parcelable superState = super.onSaveInstanceState(); SavedState ss = new SavedState(superState); //end ss.stateToSave = this.stateToSave; return ss; } @Override public void onRestoreInstanceState(Parcelable state) { //begin boilerplate code so parent classes can restore state if(!(state instanceof SavedState)) { super.onRestoreInstanceState(state); return; } SavedState ss = (SavedState)state; super.onRestoreInstanceState(ss.getSuperState()); //end this.stateToSave = ss.stateToSave; } static class SavedState extends BaseSavedState { int stateToSave; SavedState(Parcelable superState) { super(superState); } private SavedState(Parcel in) { super(in); this.stateToSave = in.readInt(); } @Override public void writeToParcel(Parcel out, int flags) { super.writeToParcel(out, flags); out.writeInt(this.stateToSave); } //required field that makes Parcelables from a Parcel public static final Parcelable.Creator&lt;SavedState&gt; CREATOR = new Parcelable.Creator&lt;SavedState&gt;() { public SavedState createFromParcel(Parcel in) { return new SavedState(in); } public SavedState[] newArray(int size) { return new SavedState[size]; } }; } } </code></pre> <p>The work is split between the View and the View's SavedState class. You should do all the work of reading and writing to and from the <code>Parcel</code> in the <code>SavedState</code> class. Then your View class can do the work of extracting the state members and doing the work necessary to get the class back to a valid state.</p> <p>Notes: <code>View#onSavedInstanceState</code> and <code>View#onRestoreInstanceState</code> are called automatically for you if <code>View#getId</code> returns a value >= 0. This happens when you give it an id in xml or call <code>setId</code> manually. Otherwise you have to call <code>View#onSaveInstanceState</code> and write the Parcelable returned to the parcel you get in <code>Activity#onSaveInstanceState</code> to save the state and subsequently read it and pass it to <code>View#onRestoreInstanceState</code> from <code>Activity#onRestoreInstanceState</code>.</p> <p>Another simple example of this is the <a href="http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/4.0.3_r1/android/widget/CompoundButton.java#CompoundButton.onSaveInstanceState%28%29" rel="noreferrer"><code>CompoundButton</code></a></p>
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    1. POHow to prevent custom views from losing state across screen orientation changes
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    1. USDaniel Lubarov
    1. USQberticus
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    1. POHow to prevent custom views from losing state across screen orientation changes
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    1. COFor those arriving here because this isn't working when using Fragments with the v4 support library, I note that the support library doesn't seem to call the View's onSaveInstanceState/onRestoreInstanceState for you; you have to explicitly call it yourself from a convenient place in the FragmentActivity or Fragment.
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      1. USmagneticMonster
    2. CONote that the CustomView you apply this to should have a unique id set, otherwise they will share state with each other. SavedState is stored against the CustomView's id, so if you have multiple CustomViews with the same id, or no id, then the parcel saved in the final CustomView.onSaveInstanceState() will be passed into all the calls to CustomView.onRestoreInstanceState() when the views are restored.
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      1. USNick Street
    3. COThis method didn't work for me with two custom views (one extending the other). I kept getting a ClassNotFoundException when restoring my view. I had to use the Bundle approach in Kobor42's answer.
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      1. USChris
 

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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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