Question

我首先尝试了示例here（getActivity）中的提示，但它不起作用

TextView text = (TextView)
getActivity().findViewById(R.nrOfBooksInCollection);//This results in nullpointer exception
text.setText("Text from a fragment");//This results in nullpointer exception

以下代码可以使用neiter。我没有在Eclipse中使用下面的代码得到错误，它只是不改变textview“nrOfBooksInCollection”中的文本。

package com.ahmad.actionBar;

import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TableLayout;
import android.widget.TextView;

public class FragMent2 extends Fragment
{
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
    View view = inflater.inflate(R.layout.summary, null);
    SimpleBookManager testBook = new SimpleBookManager();
    TextView nrOfBooksfield = (TextView) view.findViewById(R.id.nrOfBooksInCollection);
        String text = Integer.toString(testBook.count());
        nrOfBooksfield.setText(text);//The text doesn't change at all
        nrOfBooksfield.setText("text");//Neither does this
        return inflater.inflate(R.layout.summary, container, false);
    }
    }

当我使用Activities时它工作，所以XML文件很好。

Answer 1

您正在ViewGroup之外夸大您的视图。尝试：

View view = inflater.inflate(R.layout.summary, container, null);
...
return view;

使用片段将setText设置为textview

1 个答案: