我想在片段类禁用后退按钮。 onBack pressed可以fragment.how不行禁用后退按钮？..这是我简单的code。

 公共类扩展登录片段{    公共查看onCreateView（LayoutInflater充气器，容器的ViewGroup，       ，捆绑savedInstanceState）{          ViewGroup中的root =（ViewGroup中）inflater.inflate（R.layout.login，NULL）;          返回根;          }          公共无效onBack pressed（）{     }} 

解决方案

您必须覆盖onBack pressed父FragmentActivity类。因此，把你的codeS父FragmentActivity。或者，您可以使用此调用父类的方法：

 公共无效callParentMethod（）{    getActivity（）onBack pressed（）。} 

在FragmentActivity覆盖onBack pressed方法，而不是调用它的超类禁用后退按钮。

  @覆盖公共无效onBack pressed（）{  //super.onBack$p$pssed（）;  //创建一个对话框，询问是毫无疑问的用户是否想要退出  ...} 

I want to disable back button in fragment class. onBackpressed cannot work in fragment.how to disable back button?.. this is my simple code.

public class Login extends Fragment {
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
       ,Bundle savedInstanceState) {
          ViewGroup root = (ViewGroup) inflater.inflate(R.layout.login, null);
          return root;
          }
          public void onBackPressed() {
     }
}

You have to override onBackPressed of parent FragmentActivity class. Therefore, put your codes in parent FragmentActivity. Or you can call parent's method by using this:

public void callParentMethod(){
    getActivity().onBackPressed();
}

in FragmentActivity override onBackPressed Method and not call its super class to disable back button.

@Override
public void onBackPressed() {
  //super.onBackPressed();
  //create a dialog to ask yes no question whether or not the user wants to exit
  ...
}