programmatically adding SurfaceView to a FrameLayout which is Z-ordered under ImageView

EDIT 2a: feel free to jump to the bottom for succinct questions.

I can Draw a SurfaceView via xml. In my case, I am creating an e-book which will have different animations running on SurfaceViews for each page of the book.

I've got a .xml layout that has a FrameLayout called @+id/animation_layout.

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout 
        xmlns:android="http://schemas.android.com/apk/res/android" 
        android:orientation="vertical" 
        android:layout_width="match_parent"
        android:layout_height="match_parent"
    >
        <fi.harism.curl.CurlView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/curl"
        >
        </fi.harism.curl.CurlView>
        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/animation_layout"
        />
        <include layout="@layout/narration" 
        />
    </RelativeLayout>

Depending on which page of the book is being displayed, I would like to add a different instance of one of the classes in my set of classes which extend SurfaceView.

Page01SurfaceView extends PageAniSurfaceView {
    //
    // code here includes onDraw() definition
    //
}

Page02SurfaceView extends PageAniSurfaceView {
    //
    // code here includes onDraw() definition
    //
}

PageAniSurfaceView basically creates a Thread when it's instantiated and kicks off that thread when its View is created.

public class PageAniSurfaceView extends SurfaceView implements SurfaceHolder.Callback {
private final String TAG = this.getClass().getSimpleName();
private TutorialThread _thread;

public PageAniSurfaceView(Context context) 开发者_开发知识库{
    super(context);
    init();
}

public PageAniSurfaceView(Context context, AttributeSet attrs) {
    super(context, attrs);
    init();
}

public void setBackground(int bg_id)
{
    // adding the callback (this) to the surface holder to intercept events
    getHolder().addCallback(this);
    // make the PageAniSurfaceView focusable so it can handle events
    setFocusable(true);

}

protected void init()
{
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
    _thread = new TutorialThread(getHolder(), this);
    _thread.setRunning(true);
    _thread.start();
}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
    boolean retry = true;
    _thread.setRunning(false);
    while (retry) {
        try {
            _thread.join();
            retry = false;
        } catch (InterruptedException e) {
            // we will try it again and again...
        }
    }
}

protected void draw_bitmaps(Canvas canvas)
{
         // will be overridden by child classes
}

@Override
protected void onDraw(Canvas canvas) {
    if(this.getVisibility() == View.VISIBLE)
    {
        if(canvas != null)
        {
            draw_bitmaps(canvas);
        }
    }
}

public void update_bitmaps() 
{
         // will be overridden by child classes
}

public void elementStarted(PageElement _pageElement) {
    // Nothing in parent class
}

public void elementFinished(PageElement mElement) {
    // Nothing in parent class
}
}

I have a class called PageDisplayer which keeps track of which page we're on, and should addView() the specific SurfaceView class I need to include for that page.

public void displayPage()
{
    page = sSystemRegistry.pageSystem.getCurrentPage();
    mBookReader.mAnimationLayout.removeAllViews();

    PageAniSurfaceView _ani = null;

    switch(page.index)
    {
    case 1:
        _ani = new Page01SurfaceView(mBookReader);
        break;
    case 2:
        _ani = new Page02SurfaceView(mBookReader);
        break;
    case 3:
        _ani = new Page03SurfaceView(mBookReader);
        break;

    }

    if(_ani != null)
    {
        _ani.setWillNotDraw(false);
                    // mBookReader.mAnimationLayout is a FrameLayout in my .xml
        mBookReader.mAnimationLayout.addView(_ani);
        mElementDisplayer.setElementListener(_ani);
    }
}

Via breakpoints OR LogCat, I can tell the Threads are running, and the onDraws are being called. The bitmaps defined and displayed in e.g., Page01SurfaceView are drawn once, but not redrawn when update_bitmaps() changes the (x,y) coordinates of the bitmap.

Why are the bitmaps not being drawn on each call to onDraw(Canvas)?

edit: if there's an animation in a View above the bitmaps, then the bitmaps on the SurfaceView are displayed.

EDIT 2: Succinct Question:

Will an ImageView Z-ordered above a SurfaceView keep the SurfaceView from drawing itself?

Should I just be using a View and not a SurfaceView? I'm going to try that and report back.

I'm just using a View, not a SurfaceView.

Dianne Hackborn said "surface views are very special and not really views (the surface is a separate window Z-ordered with your own), their Z-ordering does not match your views. A surface view is a big, heavy object; you are not intended to treat SurfaceView like a regular view in this way."

https://groups.google.com/d/topic/android-developers/COffLpanlz0/discussion