Android fragments Onclick事件（ANDROID STUDIO）

我的代码有什么问题。我遇到一个错误，无法找到符号方法findViewByDint。Fragment是新的包。没有按钮代码部分，它可以完美地工作

public class Scanner1 extends Fragment {

    private Button scannerButton;
    @Nullable
    @Override

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

        View rootView = inflater.inflate(R.layout.scan_main,container,false);
         return rootView;


        scannerButton = (Button) findViewById(R.id.scannerButton);

        scannerButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Intent intent = new Intent(v.getContext(), BarcodeScanner.class);
                startActivity(intent);
            }
        });
    }

---

片段没有findViewById。必须使用rootView

public class Scanner1 extends Fragment {

    private Button scannerButton;
    @Nullable
    @Override

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

        View rootView = inflater.inflate(R.layout.scan_main,container,false);

        scannerButton = (Button)rootView.findViewById(R.id.scannerButton);

        scannerButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Intent intent = new Intent(v.getContext(), BarcodeScanner.class);
                startActivity(intent);
            }
        });

      return rootView;
    }
}

---

更改为scannerButton=ButtonrootView.R.id.scannerButton；还是一样。它找不到符号方法findViewByDint？！？错误：42，6错误：解析时到达文件末尾