Question

我尝试在Fragment中构建一个AlertDialog但是找不到AlertDialog Builder的正确Context。

public class LoginFragment extends Fragment {
public LoginFragment() {
    // Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_login, container, false);

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

    // Listening to register new account link
    btnEnter.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {

        // if play name already exists
            AlertDialog dialog = new AlertDialog.Builder(getActivity())
                .setCancelable(false)
                .setIcon(R.drawable.login_icon)
                .setMessage("Player Name Already Exists. Please Find a New Name.")
                .setButton("Okay", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                    }
            }).show();
        }
    });

    return rootView;
}

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
}

@Override
public void onDetach() {
    super.onDetach();
}

}

在这一行：

AlertDialog dialog = new AlertDialog.Builder(getActivity());

getActivity（）无效。它说“需要AlertDialog，发现AlertDialog.Builder”。我尝试过像this.getActivity（）和getContext（）以及getSupportFragmentManager（）这样的东西，所有这些都不起作用。我对此有点困惑。有人能告诉我应该使用哪些以及为什么？

Answer 1

AlertDialog dialog = new AlertDialog.Builder(getActivity());

应替换为

AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

Answer 2

这是一个自定义对话框，只需按照您的喜好进行编辑即可。

在片段内使用对话框的示例：

AlertDialog.Builder makeDialog = new AlertDialog.Builder(getActivity());
            LayoutInflater li = getLayoutInflater(null);
            View viewAdd = li.inflate(R.layout.random_dialog, null);
            makeDialog.setView(viewAdd);

            //editexts,textviews and that stuff goes here

            makeDialog.setPositiveButton("Save", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {




                }
            });

            makeDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            });

            AlertDialog ad = makeDialog.create();
            ad.show();

片段中的Android AlertDialog Builder getActivity（）不起作用

2 个答案: