从布局内的SurfaceView更新编程布局

Question

所以，我已经找到了答案。大多数结果显示如何从布局外部更新。这是我的简化代码。

MainActivity：

public class MainActivity extends Activity{
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {   this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, 
        WindowManager.LayoutParams.FLAG_FULLSCREEN);
        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);
        LinearLayout surface = (LinearLayout)findViewById(R.id.surface);
        surface.addView(new UnitActivity(this));}}  

UnitActivity：

public class UnitActivity extends SurfaceView
{
    private MainThread thread;
    private SurfaceHolder holder;

    public UnitActivity(Context context){
        super(context);touch = new MyTouchListener();
        this.setOnTouchListener(touch);

        thread = new MainThread(this);
        holder=getHolder();
        holder.addCallback(new SurfaceHolder.Callback(){    
            @Override
            public void surfaceCreated(SurfaceHolder p1)
            {
                thread.setRunning(true);
                thread.start();         
            }

            @Override
            public void surfaceChanged(SurfaceHolder p1, int p2, int p3, int p4)
            {
                // TODO: Implement this method
            }
            @Override
            public void surfaceDestroyed(SurfaceHolder p1)
            {
                boolean retry = true;
                while (retry)
                {
                    try
                    {
                        thread.join();
                        retry = false;
                    }
                    catch(Exception e){
                    }
                }
            }       
        });
    setFocusable(true)
    }
    @Override 
    public void onDraw(Canvas c) {
        //draw to canvas here
        *******Here is where I want to, in some way 
        make a call to add a ScrollView or 
        TextView to the original Layout******
    }
} 

基本上，我的SurfaceView正在更新运行Thread。我希望某个条件触发TextView或ScrollView在屏幕上显示。我想也许我可以让布局运行一个线程并更新自己，但杀了我的应用程序这样做...我感谢任何帮助或评论。