尝试在空对象引用上调用虚拟方法“void android.widget.Button.setVisibility(int)”

Question

我已将按钮的可见性设置为“消失”，但是现在当我想将按钮设置为可见时，尝试设置按钮的可见性时出现以下错误

    @Bind(R.id.btn1)
    Button btn1;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        View view = inflater.inflate(R.layout.hifragment_main, container, false);

      if(1==1) 
        {
            btn1.setVisibility(View.VISIBLE);
        }
        return view;
    }

Answer 1

你没有初始化你的按钮，请按如下方式初始化它，

View view = inflater.inflate(R.layout.hifragment_main, container, false);
btn1 = (Button) view.findViewById(R.id.btn1);