Question

我希望从班级

更改视图linearlayout

但不能使用此代码

main.java

public class MainActivity extends Activity {

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

并且：

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);
    }
}

如何在班级lnrPart）中main.xml更改ComNet？

Answer 1

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

使用此行，您将创建一个新的View，其内容为main.xml。此对象与您在MainActivity屏幕上看到的对象不同。 setVisibility正在发挥作用。你在错误的实例上调用它

Answer 2

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);
}

Android：setVisibility不起作用

2 个答案: