編輯:Android開發實例
ListFragment繼承於Fragment。因此它具有Fragment的特性,能夠作為activity中的一部分,目的也是為了使頁面設計更加靈活。
相比Fragment,ListFragment的內容是以列表(list)的形式顯示的。ListFragment的布局默認包含一個ListView。因此,在ListFragment對應的布局文件中,必須指定一個 android:id 為 “@android:id/list” 的ListView控件!
ListFragment基礎使用
下面介紹在Activity中顯示ListFragment的步驟。
1. Activity對應的代碼
public class FragmentTest extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); } }
2. Activity對應的布局
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal" > <fragment android:name="com.skw.fragmenttest.MyListFragment" android:id="@+id/myfragment" android:layout_width="match_parent" android:layout_height="match_parent" /> </LinearLayout>
說明:該Activity的布局中只包行了一個Fragment。下面看看MyListFragment的內容。
3. MyListFragment的內容
public class MyListFragment extends ListFragment { private static final String TAG = "##MyListFragment##"; private ListView selfList; String[] cities = { "Shenzhen", "Beijing", "Shanghai", "Guangzhou", "Wuhan", "Tianjing", "Changsha", "Xi'an", "Chongqing", "Guilin", }; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { Log.d(TAG, "onCreateView"); return inflater.inflate(R.layout.list_fragment, container, false); } @Override public void onCreate(Bundle savedInstanceState) { Log.d(TAG, "onCreate"); super.onCreate(savedInstanceState); // 設置ListFragment默認的ListView,即@id/android:list this.setListAdapter(new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, cities)); } public void onListItemClick(ListView parent, View v, int position, long id) { Log.d(TAG, "onListItemClick"); Toast.makeText(getActivity(), "You have selected " + cities[position], Toast.LENGTH_SHORT).show(); } }
說明:MyListFragment是自定義的ListFragment。它使用了list_fragment.xml作為布局,並通過android.R.layout.simple_list_item_1顯示ListView中的每一項。
4. list_fragment.xml的內容
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <!-- ListFragment對應的android:id值固定為"@id/android:list" --> <ListView android:id="@id/android:list" android:layout_width="match_parent" android:layout_height="match_parent" android:drawSelectorOnTop="false" /> </LinearLayout>
"Activity的布局以及代碼"和前面一樣,這裡就不再重復說明。
5. MyListFragment的內容
public class MyListFragment extends ListFragment { private static final String TAG = "##MyListFragment##"; private ListView selfList; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { Log.d(TAG, "onCreateView"); return inflater.inflate(R.layout.list_fragment, container, false); } @Override public void onCreate(Bundle savedInstanceState) { final String[] from = new String[] {"title", "info"}; final int[] to = new int[] {R.id.text1, R.id.text2}; Log.d(TAG, "onCreate"); super.onCreate(savedInstanceState); // 建立SimpleAdapter,將from和to對應起來 SimpleAdapter adapter = new SimpleAdapter( this.getActivity(), getSimpleData(), R.layout.item, from, to); this.setListAdapter(adapter); } public void onListItemClick(ListView parent, View v, int position, long id) { Log.d(TAG, "onListItemClick"); Toast.makeText(getActivity(), "You have selected " + position, Toast.LENGTH_SHORT).show(); } private List<Map<String, Object>> getSimpleData() { List<Map<String, Object>> list = new ArrayList<Map<String, Object>>(); Map<String, Object> map = new HashMap<String, Object>(); map.put("title", "Ferris wheel"); map.put("info", "Suzhou Ferris wheel"); list.add(map); map = new HashMap<String, Object>(); map.put("title", "Flower"); map.put("info", "Roser"); list.add(map); map = new HashMap<String, Object>(); map.put("title", "Disk"); map.put("info", "Song Disk"); list.add(map); return list; } }
說明:MyListFragment使用了R.layout.list_fragment作為布局,並且對於ListView中的每一項都使用了R.layout.item作為布局。
6. list_fragment.xml的內容
<!-- ListFragment對應的android:id值固定為"@id/android:list" -->
<ListView
android:id="@id/android:list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:drawSelectorOnTop="false"
/>
7. item.xml的內容
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <TextView android:id="@+id/text1" android:textSize="12sp" android:text android:layout_width="match_parent" android:layout_height="wrap_content"/> <TextView android:id="@+id/text2" android:textSize="24sp" android:layout_width="match_parent" android:layout_height="wrap_content"/> </LinearLayout>
ListFragment實例
應用實例說明:建立一個activity,包括2個ListFragment。第1個ListFragment采用中ListView每一行的內容通過android自帶的android.R.layout.simple_list_item_1布局來顯示;第2個ListFragment每一行的內容通過自定義的layout文件來顯示,每一行顯示兩個文本。
activity對應的layout文件代碼:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal" > <fragment android:name="com.skywang.app.ListFragmentImpl" android:id="@+id/fragment1" android:layout_weight="1" android:layout_width="match_parent" android:layout_height="match_parent" /> <fragment android:name="com.skywang.app.ListFragmentSelf" android:id="@+id/fragment2" android:layout_weight="1" android:layout_width="match_parent" android:layout_height="match_parent" /> </LinearLayout>
說明:
(01) 該layout布局包含兩個fragment。
activity的代碼:
package com.skywang.app; import android.os.Bundle; import android.app.Activity; import android.app.FragmentManager; import android.app.FragmentTransaction; import android.view.Menu; public class ListFragmentTest extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.list_fragment_test); } }
說明:
(01) 在 onCreateView()中,調用list_fragment_impl作為該ListFragment的布局文件。
(02) 在 onCreate()中,通過setListAdapter() 設置android.R.layout.simple_list_item_1為ListView每一行的布局文件,設置cities為其中數據的每一項內容。
ListFragmentImpl.java的代碼:
package com.skywang.app; import android.app.ListFragment; import android.widget.ListView; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import android.util.Log; import android.widget.Toast; import android.widget.SimpleAdapter; import java.util.Map; import java.util.HashMap; import java.util.List; import java.util.ArrayList; public class ListFragmentImpl extends ListFragment{ private static final String TAG = "ListFragmentImpl"; private ListView selfList; String[] cities = { "Shenzhen", "Beijing", "Shanghai", "Guangzhou", "Wuhan", "Tianjing", "Changsha", "Xi'an", "Chongqing", "Guilin", }; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { Log.d(TAG, "onCreateView"); return inflater.inflate(R.layout.list_fragment_impl, container, false); } @Override public void onCreate(Bundle savedInstanceState) { Log.d(TAG, "onCreate"); super.onCreate(savedInstanceState); // 設置ListFragment默認的ListView,即@id/android:list this.setListAdapter(new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, cities)); } public void onListItemClick(ListView parent, View v, int position, long id) { Log.d(TAG, "onListItemClick"); Toast.makeText(getActivity(), "You have selected " + cities[position], Toast.LENGTH_SHORT).show(); } }
list_fragment_impl.xml的內容:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <!-- ListFragment對應的android:id值固定為"@id/android:list" --> <ListView android:id="@id/android:list" android:layout_width="match_parent" android:layout_height="match_parent" android:drawSelectorOnTop="false" /> </LinearLayout>
ListFragmentSelf.java的代碼:
package com.skywang.app;
import android.app.ListFragment; import android.widget.ListView; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import android.util.Log; import android.widget.Toast; import android.widget.SimpleAdapter; import java.util.Map; import java.util.HashMap; import java.util.List; import java.util.ArrayList; public class ListFragmentSelf extends ListFragment{ private static final String TAG = "ListFragmentImpl"; private ListView selfList; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { Log.d(TAG, "onCreateView"); return inflater.inflate(R.layout.list_fragment_self, container, false); } @Override public void onCreate(Bundle savedInstanceState) { final String[] from = new String[] {"title", "info"}; final int[] to = new int[] {R.id.text1, R.id.text2}; Log.d(TAG, "onCreate"); super.onCreate(savedInstanceState); // 建立SimpleAdapter,將from和to對應起來 SimpleAdapter adapter = new SimpleAdapter( this.getActivity(), getSimpleData(), R.layout.two_textview, from, to); this.setListAdapter(adapter); } public void onListItemClick(ListView parent, View v, int position, long id) { Log.d(TAG, "onListItemClick"); Toast.makeText(getActivity(), "You have selected " + position, Toast.LENGTH_SHORT).show(); } private List<Map<String, Object>> getSimpleData() { List<Map<String, Object>> list = new ArrayList<Map<String, Object>>(); Map<String, Object> map = new HashMap<String, Object>(); map.put("title", "Ferris wheel"); map.put("info", "Suzhou Ferris wheel"); list.add(map); map = new HashMap<String, Object>(); map.put("title", "Flower"); map.put("info", "Roser"); list.add(map); map = new HashMap<String, Object>(); map.put("title", "Disk"); map.put("info", "Song Disk"); list.add(map); return list; } }
說明:
(01) 在 onCreateView()中,調用list_fragment_self作為該ListFragment的布局文件。
(02) 在 onCreate()中,通過setListAdapter() 設置R.layout.two_textview為ListView每一行的布局文件。
list_fragment_self.xml的內容:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <!-- ListFragment對應的android:id值固定為"@id/android:list" --> <ListView android:id="@id/android:list" android:layout_width="match_parent" android:layout_height="match_parent" android:drawSelectorOnTop="false" /> </LinearLayout>
two_textview.xml的內容:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <TextView android:id="@+id/text1" android:textSize="12sp" android:text android:layout_width="match_parent" android:layout_height="wrap_content"/> <TextView android:id="@+id/text2" android:textSize="24sp" android:layout_width="match_parent" android:layout_height="wrap_content"/> </LinearLayout>
效果圖:
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