Onclick事件（ANDROID STUDIO）

Question

我的代码有什么问题。我得到一个错误“找不到符号方法findViewById（int）”。片段是新的包装。没有按钮代码部分，它完美的工作。

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); 
      } 
     }); 
    } 

Answer 1

片段没有findViewById。您必须使用您的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; 
    } 
}