Android Fragment實現列表和內容聯動

2019-10-21 21:30:49

字體：大中小

來源：轉載

供稿：網友

在平板上經常能看到這種的情況：左邊是一個列表，右邊是列表項對應的內容，當點擊某一個列表時，右邊內容區也會隨之改變。下面使用Fragment簡單的demo：

思路：在MainActivity定義一個回調接口，并在列表點擊回調該接口，然后在內容區的Fragment設置回調，同時改變Fragment的顯示內容。具體代碼如下：

主布局：

<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="?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>

ListView的item布局和內容區Fragment的布局都比較簡單，分別是一個Textview和兩個Textview布局，這里不再貼出。

MainActivity類（內容區的數據是寫死的，僅僅做演示作用，一般來說需要從網絡上獲取數據）：

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("瘋狂Java講義");    book1.setDesc("一本全面的，深入的Java學習圖書，受到廣大讀者的熱烈喜愛，已經被多家高校選為教材，成為國內一線的Java學習素材");    books.add(book1);    Book book2 = new Book();    book2.setId(2);    book2.setName("瘋狂Android講義");    book2.setDesc("Android學習者的首選教材，常年占據京東，當當，亞馬遜3大網店Android銷量排行榜首，是人人可必備的Android入門圖書");    books.add(book2);    Book book3 = new Book();    book3.setId(3);    book3.setName("Java EE企業應用實戰");    book3.setDesc("全面介紹Java EE開發的Struts2 ， Spring 3 ， Hibernate 4 架構，可以通過該書系統學習企業級開發，全面掌握Java學習");    books.add(book3);    Book book4 = new Book();    book4.setId(4);    book4.setName("HTML5開發");    book4.setDesc("全面介紹HTML5，CSS ，JavaScript等知識點，通過該書可以系統的學習Web前端開發，通常Javascript腳本設置動態頁面");    books.add(book4);  }  public void setOnChangeListener(OnChangeListener onChangeListener)  {    this.onchangedListener = onChangeListener;  }  interface OnChangeListener  {    void changeText(Book book);  }}

列表的Adapter類：

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;  }}

內容區的Fragment類：

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);    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;  }}

Book實體類：

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;  }}

效果：

Android,Fragment,列表,內容聯動