ActivityGroup的使用代码将子activty 的layout加入到主activity中

想代码实现 将子activity的所用的layout加入到主activty中的layout

public class FormActivity extends ActivityGroup { 
 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
 
    setContentView(R.layout.form); 
 
    LocalActivityManager m = getLocalActivityManager(); 
 
    Intent intent = new Intent().setClass(this, ContactFieldActivity.class); 
    Window w = m.startActivity("tratat", intent); 
 
    View v = w.getDecorView(); 
 
    LinearLayout container = (LinearLayout)findViewById(R.id.fieldsContainer); 
    container.addView(v); 
  } 
 
 
}