將Fragment與Layout結(jié)合使用,一般都是主Activity以frame填充Activity的方式交互管理Fragment :
1.由于用到getSupportFragmentManager()之類,所以主Activity的extends需為FragmentActivity:
public class MainActivity extends FragmentActivity{ .......... }2.主Activity的layout(xml文件)中建立多個(gè)Frame并定義其Android:id="@+id/XXX"
3.主Activity內(nèi)操作函數(shù)中,由查找id來(lái)對(duì)這些FrameLayout進(jìn)行Activity填充:
添加語(yǔ)句如下
取得支持Fragment管理()->開始交易()->添加(frame的id , Fragment).交付();
替換語(yǔ)句如下
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container2,new NullFrag()).commit();
取得支持Fragment管理()->開始交易()->替代(frame的id , Fragment).交付();
例:
下面我們來(lái)看實(shí)例:

效果圖的左邊是一個(gè)列表,右邊是列表item的詳情。
先看一下布局文件(layout):
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="match_parent" android:layout_height="match_parent"> <fragment class="com.fragment.main.TitlesFragment" android:id="@+id/titles" android:layout_weight="1" android:layout_width="0px" android:layout_height="match_parent" /> <FrameLayout android:id="@+id/details" android:layout_weight="1" android:layout_width="0px" android:layout_height="match_parent" android:background="?android:attr/detailsElementBackground" /> </LinearLayout>
布局文件中使用了fragment標(biāo)簽和FrameLayout標(biāo)簽。Android Fragment使用 中介紹了2中嵌入Fragment的方法,這個(gè)實(shí)例中都用到,從布局文件看到有了fragment標(biāo)簽,這是一種使用方法,F(xiàn)rameLayout標(biāo)簽將會(huì)成為第二種加載fragment的載體view。
看一下程序?qū)崿F(xiàn)(com.fragment.main.TitlesFragment):
public class TitlesFragment extends ListFragment { int mCurCheckPosition = 0; int mShownCheckPosition = -1; @Override public void onActivityCreated(Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); setListAdapter(new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_activated_1, Shakespeare.TITLES)); //使用靜態(tài)數(shù)組填充列表 if (savedInstanceState != null) { mCurCheckPosition = savedInstanceState.getInt("curChoice", 0); mShownCheckPosition = savedInstanceState.getInt("shownChoice", -1); } getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE); showDetails(mCurCheckPosition); } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putInt("curChoice", mCurCheckPosition); outState.putInt("shownChoice", mShownCheckPosition); } @Override public void onListItemClick(ListView l, View v, int position, long id) { showDetails(position); } /** *顯示listview item 詳情 */ void showDetails(int index) { mCurCheckPosition = index; getListView().setItemChecked(index, true); if (mShownCheckPosition != mCurCheckPosition) { DetailsFragment df = DetailsFragment.newInstance(index); FragmentTransaction ft = getFragmentManager() .beginTransaction(); ft.replace(R.id.details, df); ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE); ft.commit(); mShownCheckPosition = index; } } } TitlesFragment
TitlesFragment繼承自Fragment的子類ListFragment,使用了一個(gè)靜態(tài)數(shù)組填充列表,重寫了onListItemClick方法,showDetails方法展示ListView item的詳情。
DetailsFragment df = DetailsFragment.newInstance(index);//獲取詳情Fragment的實(shí)例FragmentTransaction ft = getFragmentManager().beginTransaction();//獲取FragmentTransaction 實(shí)例ft.replace(R.id.details, df); //使用DetailsFragment 的實(shí)例ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);ft.commit();//提交
看一下DetailsFragment :
public class DetailsFragment extends Fragment { /** * Create a new instance of DetailsFragment, initialized to * show the text at 'index'. */ public static DetailsFragment newInstance(int index) { DetailsFragment f = new DetailsFragment(); // Supply index input as an argument. Bundle args = new Bundle(); args.putInt("index", index); f.setArguments(args); return f; } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { if (container == null) { return null; } ScrollView scroller = new ScrollView(getActivity()); TextView text = new TextView(getActivity()); int padding = (int) TypedValue.applyDimension( TypedValue.COMPLEX_UNIT_DIP, 4, getActivity().getResources() .getDisplayMetrics()); text.setPadding(padding, padding, padding, padding); scroller.addView(text); text.setText(Shakespeare.DIALOGUE[getArguments().getInt("index", 0)]); return scroller; } }
DetailsFragment 中使用newInstance(int index)方法產(chǎn)生DetailsFragment 實(shí)例并接受整型參數(shù),重載了onCreateView方法創(chuàng)建view。
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