安卓：setVisibility不行

Question

我想从

类更改视图 linearlayout

但不起作用此代码

main.java

public class MainActivity extends Activity { 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     ComNet.readDb(); 
    } 
} 

和：

ComNet.java

public class ComNet { 
    public static Context context; 

    public static void readDb() { 

     LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     View viewMain = inflater.inflate(R.layout.main, null); 
     LinearLayout lnrPart = (LinearLayout) viewMain.findViewById(R.id.lnrPart); 
     lnrPart.setVisibility(View.GONE); 
    } 
} 

如何从main.xml类（ComNet）改变lnrPart？

Answer 1

将活动rootView发送到readDB函数。

main.java

public class MainActivity extends Activity { 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 
    ComNet.readDb(findViewById(R.id.main)); 
    } 
} 

ComNet.java

public static void readDb(View viewMain) { 

    LinearLayout lnrPart = (LinearLayout) viewMain.findViewById(R.id.lnrPart); 
    viewMain.setVisibility(View.GONE); 
} 

Answer 2

View viewMain = inflater.inflate(R.layout.main, null); 

这一行，你要创建一个新View，随着main.xml内容。该对象与您在MainActivity屏幕上看到的对象不同。 setVisibility正在工作。您在错误的实例上调用它