Android 无法使用LayoutInfalter呈现xml布局。我做错了什么？

我需要从xml文件中显示布局，并在上面绘制一些基于向量的图像。如果执行了下面的代码，那么除了布局之外，所有内容都会显示出来。为什么？我做错了什么

public class About extends Activity 
{
@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    //setContentView(R.layout.about); 
    setContentView(new GraphicsView(this));
}

public class GraphicsView extends View
{
    public GraphicsView(Context context)
    {
        super(context);                 
    }
    @Override
    protected void onDraw(Canvas canvas)
    {
        Context context;
        context=getContext();

        View aview; 

        LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);    
        aview = inflater.inflate(R.layout.about, null);                 

        aview.draw(canvas);

        Path circle = new Path();
        Paint cPaint = new Paint(); 
        cPaint.setColor(Color.LTGRAY);
        circle.addCircle(150, 150, 100, Direction.CW);
        canvas.drawPath(circle, cPaint);
        cPaint.setColor(Color.RED);
        canvas.drawTextOnPath("Some stupid text", circle, 0, 20, cPaint);
    }
}

---

}

在对视图进行充气后，您需要对其进行测量并进行布局，以确定其大小，以便正确绘制。在调用aview.draw之前，应该调用aview.measure和aview.layout

---

请注意，永远不要从onDraw中膨胀视图。它既昂贵又浪费。同样，您也不应该在onDraw中创建绘画或路径。

另一个论坛给出了另一个答案：

框架布局：

 public class About extends Activity 
 { 
    @Override 
    protected void onCreate(Bundle savedInstanceState) 
    { 
       super.onCreate(savedInstanceState); 
       setContentView(R.layout.about);

       GraphicsView drawing = new GraphicsView(this);

       FrameLayout container = (FrameLayout) findViewById(R.id.container);
       container.addView(drawing);
    } 

    public class GraphicsView extends View 
    { 
       public GraphicsView(Context context) 
       { 
          super(context);                 
       } 
       @Override 
       protected void onDraw(Canvas canvas) 
       { 
          Path circle = new Path(); 
          Paint cPaint = new Paint(); 
          cPaint.setColor(Color.LTGRAY); 
          circle.addCircle(150, 150, 100, Direction.CW); 
          canvas.drawPath(circle, cPaint); 
          cPaint.setColor(Color.RED); 
          canvas.drawTextOnPath("Some stupid text", circle, 0, 20, cPaint); 
       } 
    } 
 }

接下来是XML：

<?xml version="1.0" encoding="utf-8"?> 
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:padding="10dip" 
    android:id="@+id/container"> 
    <TextView 
        android:id="@+id/about_content" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:text="@string/about_text" />
</FrameLayout>