添加content前requestFeature()必须被调用？

Question

我试图实现一个自定义titlebar.
以下是Helper class:

import android.app.Activity;
import android.view.Window;

public class UIHelper {
    public static void setupTitleBar(Activity c) {
        final boolean customTitleSupported = c.requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);

        c.setContentView(R.layout.main);

        if (customTitleSupported) {
            c.getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.titlebar);
        }
    }
}

这是在onCreate()中调用的方法:

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setupUI();
    }

private void setupUI(){
         setContentView(R.layout.main);
         UIHelper.setupTitleBar(this);
    }

错误提醒：

requestFeature() must be called before adding content

在添加content前requestFeature()必须被调用吗？

Answer 1

正如提示里说的，不要在requestFeature()调用setContentView()。
另一个选择是使用AsyncTask对话框。

public class CustomDialog extends AlertDialog {

   private View content;

   public CustomDialog(Context context) {
       super(context);

       LayoutInflater li = LayoutInflater.from(context);
       content = inflater.inflate(R.layout.custom_view, null);

       setUpAdditionalStuff(); 
       setView(content);           
   }

   private void setUpAdditionalStuff();
       // ...
   }

   // 在 onPrepareDialog() 方法中调用 ((CustomDialog) dialog).prepare()   
   public void prepare() {
       setTitle(R.string.custom_title);
       setIcon( getIcon() );
       // ...
   }
}