<LinearLayout XMlns:andROId="http://schemas.android.COM/apk/res/android"   android:orientation="horizontal"   android:layout_width="match_parent"   android:layout_height="match_parent"   android:layout_marginLeft="16dp"   android:layout_marginRight="16dp"   android:divider="&#63;android:attr/dividerVertical"   android:showDividers="middle">    <ListView     android:id="@+id/Book_list"     android:layout_width="0dp"     android:layout_height="match_parent"     android:layout_weight="1"/>    <FrameLayout     android:id="@+id/book_detail_container"     android:layout_width="0dp"     android:layout_height="match_parent"     android:layout_weight="3"/>  </LinearLayout>

 public class MainActivity extends Activity {   PRivate OnChangeListener onchangedListener;   List<Book> books;   List<String> book_name = new ArrayList<>();   ListView listView;   Adapter adapter;   @override   protected void onCreate(Bundle savedInstancestate)   {     suPEr.onCreate(savedInstanceState);     setContentView(R.layout.main);     books = new ArrayList<>();     initData();     for (int i = 0 ; i < books.size() ; i++)     {       book_name.add(books.get(i).getName());     }      listView = (ListView) findViewById(R.id.book_list);     adapter = new Adapter(book_name , this);     listView.setAdapter(adapter);      MyFragment fragment = new MyFragment();     FragmentManager fragmentManager = getFragmentManager();     FragmentTransaction transaction = fragmentManager.beginTransaction();     transaction.replace(R.id.book_detail_container , fragment);     transaction.commit();      listView.setOnItemClickListener(new AdapterView.OnItemClickListener()     {       @Override       public void onItemClick(AdapterView<?> parent, View view, int position, long id)       {         adapter.setSelectedPosition(position);         adapter.notifyDataSetInvalidated();          if (onchangedListener != null)         {           onchangedListener.changeText(books.get(position));         }       }     });   }    private void initData()   {     Book book1 = new Book();     book1.setId(1);     book1.setName("疯狂Java讲义");     book1.setDesc("一本全面的，深入的Java学习图书，受到广大读者的热烈喜爱，已经被多家高校选为教材，成为国内一线的Java学习素材");     books.add(book1);      Book book2 = new Book();     book2.setId(2);     book2.setName("疯狂Android讲义");     book2.setDesc("Android学习者的首选教材，常年占据京东，当当，亚马逊3大网店Android销量排行榜首，是人人可必备的Android入门图书");     books.add(book2);      Book book3 = new Book();     book3.setId(3);     book3.setName("Java EE企业应用实战");     book3.setDesc("全面介绍Java EE开发的Struts2 ， Spring 3 ， Hibernate 4 架构，可以通过该书系统学习企业级开发，全面掌握Java学习");     books.add(book3);      Book book4 = new Book();     book4.setId(4);     book4.setName("HTML5开发");     book4.setDesc("全面介绍HTML5，CSS ，JavaScript等知识点，通过该书可以系统的学习Web前端开发，通常Javascript脚本设置动态页面");     books.add(book4);   }    public void setOnChangeListener(OnChangeListener onChangeListener)   {     this.onchangedListener = onChangeListener;   }    interface OnChangeListener   {     void changeText(Book book);   } }

 public class Adapter extends BaseAdapter {   private List<String> mData;   private LayoutInflater layoutInflater;   private int selectionPosition = -1;   public Adapter(List<String> data , Context context)   {     this.mData = data;     this.layoutInflater = LayoutInflater.From(context);   }    @Override   public int getCount()   {     return mData.size();   }    @Override   public Object getItem(int position)   {     return mData.get(position);   }    @Override   public long getItemId(int position)   {     return position;   }    @Override   public View getView(int position, View convertView, ViewGroup viewGroup)   {     ViewHolder viewHolder = null;     if (convertView == null)     {       viewHolder = new ViewHolder();       convertView = layoutInflater.inflate(R.layout.item_layout , null);       viewHolder.tv = (TextView) convertView.findViewById(R.id.item_text);       convertView.setTag(viewHolder);     }     else     {       viewHolder = (ViewHolder) convertView.getTag();     }      viewHolder.tv.setText(mData.get(position));     if (selectionPosition == position)     {       viewHolder.tv.setBackgroundColor(Color.YELLOW);     }     else     {       viewHolder.tv.setBackgroundColor(Color.WHITE);     }     return convertView;   }    public void setSelectedPosition(int position)   {     this.selectionPosition = position;   }    class ViewHolder   {     TextView tv;   } }

 public class MyFragment extends Fragment {   MainActivity activity;   private TextView title;   private TextView desc;   @Nullable   @Override   public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)   {     View view = inflater.inflate(R.layout.fragment_book_detail , null);     title = (TextView) view.findViewById(R.id.book_title);     desc = (TextView) view.findViewById(R.id.book_desc);     LOG.d("fragment" , "Created");     activity = (MainActivity) getActivity();     activity.setOnChangeListener(new MainActivity.OnChangeListener()     {       @Override       public void changeText(Book book)       {         title.setText(book.getName());         desc.setText(book.getDesc());       }     });     return view;   } }

 public class Book {   private int id;   private String name;   private String desc;   public Book()   {   }    public Book(int id , String name , String desc)   {     this.id = id;     this.name = name;     this.desc = desc;   }    public void setName(String name) {     this.name = name;   }    public void setId(int id) {     this.id = id;   }    public void setDesc(String desc) {     this.desc = desc;   }    public int getId() {     return id;   }    public String getName() {     return name;   }    public String getDesc() {     return desc;   } }