学步园

Here's a drop-in solution if anyone is interested. Just derive from BetterActivity instead of Activity. This will clean up all the drawables on orientation change, and likely on activity switches etc...

public abstract class BetterActivity extends Activity
{
  @Override
  protected void onResume()
  {
    System.gc();
    super.onResume();
  }
  
  @Override
  protected void onPause()
  {
    super.onPause();
    System.gc();
  }
  
  @Override
  public void setContentView(int layoutResID)
  {
    ViewGroup mainView = (ViewGroup)
      LayoutInflater.from(this).inflate(layoutResID, null);
    
    setContentView(mainView);
  }
  
  @Override
  public void setContentView(View view)
  {
    super.setContentView(view);
    
    m_contentView = (ViewGroup)view;
  }
  
  @Override
  public void setContentView(View view, LayoutParams params)
  {
    super.setContentView(view, params);
    
    m_contentView = (ViewGroup)view;
  }
  
  @Override
  protected void onDestroy()
  {
    super.onDestroy();
    
    // Fixes android memory  issue 8488 :
    // http://code.google.com/p/android/issues/detail?id=8488
    nullViewDrawablesRecursive(m_contentView);
    
    m_contentView = null;
    System.gc();
  }
  
  private void nullViewDrawablesRecursive(View view)
  {
    if(view != null)
    {
      try
      {
        ViewGroup viewGroup = (ViewGroup)view;
        
        int childCount = viewGroup.getChildCount();
        for(int index = 0; index < childCount; index++)
        {
          View child = viewGroup.getChildAt(index);
          nullViewDrawablesRecursive(child);
        }
      }
      catch(Exception e)
      {          
      }
      
      nullViewDrawable(view);
    }    
  }

  private void nullViewDrawable(View view)
  {
    try
    {
      view.setBackgroundDrawable(null);
    }
    catch(Exception e)
    {          
    }
    
    try
    {
      ImageView imageView = (ImageView)view;
      imageView.setImageDrawable(null);
      imageView.setBackgroundDrawable(null);
    }
    catch(Exception e)
    {          
    }
  }

  // The top level content view.
  private ViewGroup m_contentView = null;
}