Android的常见错误及解决办法

一、错误：Unknown host api.tudou.com, throwing UnknownHostException。
      解决办法：在AndroidManifest.xml中添加
二、Unable to find explicit activity class  have you declared this activity in your AndroidManifest.xml?
     解决办法：在AndroidManifest.xml的application段添加声明：,详情见：
                    http://stackoverflow.com/questions/736571/using-intent-in-an-android-application-to-show-another-activity
三、ListActivity setContentView错误：
代码及相关xml如下：
main.xml:

            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:drawSelectorOnTop="false"/>
tudouPlayer.java:
public class tudouPlayer extends ListActivity implements OnClickListener {  
  
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}
编译不会报错，运行时，adb打出来的错误为：
E/AndroidRuntime(  701): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.java.tudouPlayer/com.java.tudouPlayer.tudouPlayer}: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'
解决办法：
将main.xml中，上面贴出来的那段改为（原因见注释）：            
       
       <!-- Here is the list. Since we are using a ListActivity, we
             have to call it "@android:id/list" so ListActivity will
             find it -->
      
        <ListView android:id="@android:id/list"（在ListActivity中的main.xml中不能用android:id = "@+id/list"来加list的id，不然adb 也会报错setContentView(R.layout.main);）
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:drawSelectorOnTop="false"/>