正在学习Tag ，想知道 TabHost tabs = getTabHost();为什么报错

import com.example.mess.next.New; 


 import android.app.Activity; 
 import android.content.Intent; 
 import android.content.res.Resources; 
 import android.os.Bundle; 
 import android.view.Menu; 
 import android.widget.TabHost; 


 public class MainActivity extends Activity { 


 @Override 
 protected void onCreate(Bundle savedInstanceState) { 



        super.onCreate(savedInstanceState); 
        setContentView(R.layout.main); 
        super.onCreate(savedInstanceState); 
        setContentView(R.layout.maingai); 
                 
        TabHost tabs = getTabHost();    错误：The method getTabHost() is undefined for the type MainActivity 
        TabHost.TabSpec spec = null; 
        //通过Intent，将activity导入，对于intent，这个类不能是内部类，这个类必须在AndroidManifest中注册的类 
        Intent intent = new Intent(); 
        intent.setClass(MainActivity.this,New.class); 
        spec = tabs.newTabSpec("Tag1"); 
        spec.setIndicator("Intent"); 
        spec.setContent(intent); 
        tabs.addTab(spec); 
    }