Android Fragment和FragmentActivity用法

標籤：android   class   blog   code   java   http   

Android Fragment是Android4.0以上才有的；而FragmentActivity是為了相容4.0以下版本的Fragment使用的。

所以如果你想相容4.0以下Android版本使用Fragment的話，架構Activity需要繼承FragmentActivity，FragmentActivity這個類是在android.support.v4.app.FragmentActivity裡的。

下面介紹2種用法：

1、繼承Activity的。

（這個只針對4.0以上的Android平台使用Fragment）。

架構Activity：

package com.tandong.fragment;import android.app.Activity;import android.app.Fragment;import android.app.FragmentManager;import android.app.FragmentTransaction;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;/** * 不相容4.0以下模式Fragment *  * @author tandong *  */public class Mt_Activity extends Activity implements OnClickListener {private Button btn_first, btn_second;private Fragment Fragment_first, Fragment_Second;private FragmentTransaction fragmentTransaction;private FragmentManager fragmentManager;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.fragment);initView();Fragment_Second = new Fragment_Second();fragmentManager = this.getFragmentManager();fragmentTransaction = fragmentManager.beginTransaction();fragmentTransaction.replace(R.id.main_fragment_layout, Fragment_Second,"second_Fragment").commit();}private void initView() {btn_first = (Button) this.findViewById(R.id.btn_first);btn_second = (Button) this.findViewById(R.id.btn_second);btn_first.setOnClickListener(this);btn_second.setOnClickListener(this);}@Overridepublic void onClick(View arg0) {switch (arg0.getId()) {case R.id.btn_first:// 載入不同的Fragmentif (null == Fragment_first) {Fragment_first = new Fragment_first();}fragmentTransaction = fragmentManager.beginTransaction();fragmentTransaction.replace(R.id.main_fragment_layout, Fragment_first, "fist_Fragment");fragmentTransaction.commit();break;case R.id.btn_second:if (null == Fragment_first) {Fragment_Second = new Fragment_Second();}fragmentTransaction = fragmentManager.beginTransaction();fragmentTransaction.replace(R.id.main_fragment_layout, Fragment_Second, "second_Fragment");fragmentTransaction.commit();break;default:break;}}}

Fragment代碼：

package com.tandong.fragment;import android.app.Fragment;import android.os.Bundle;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;public class Fragment_Second extends Fragment {      private View rootView;@Overridepublic View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {// TODO Auto-generated method stubif(container==null)return null;rootView=inflater.inflate(R.layout.fragment_two, container,false);return rootView;}}

2.繼承FragmentActivity的（向下相容4.0以下版本使用Fragment，匯入的是android.support.v4包裡的內容）

架構Activity：

package com.tandong.fragment;import android.os.Bundle;import android.support.v4.app.Fragment;import android.support.v4.app.FragmentActivity;import android.support.v4.app.FragmentManager;import android.support.v4.app.FragmentTransaction;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;/** * 相容4.0以下模式Fragment *  * @author tandong *  */public class Mt_Activity extends FragmentActivity implements OnClickListener {private Button btn_first, btn_second;private Fragment Fragment_first, Fragment_Second;private FragmentTransaction fragmentTransaction;private FragmentManager fragmentManager;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.fragment);initView();Fragment_first = new Fragment_first();fragmentManager = this.getSupportFragmentManager();fragmentTransaction = fragmentManager.beginTransaction();fragmentTransaction.replace(R.id.main_fragment_layout, Fragment_first,"first_Fragment").commit();}private void initView() {btn_first = (Button) this.findViewById(R.id.btn_first);btn_second = (Button) this.findViewById(R.id.btn_second);btn_first.setOnClickListener(this);btn_second.setOnClickListener(this);}@Overridepublic void onClick(View arg0) {switch (arg0.getId()) {case R.id.btn_first:// 載入不同的Fragmentif (null == Fragment_first) {Fragment_first = new Fragment_first();}fragmentTransaction = fragmentManager.beginTransaction();fragmentTransaction.replace(R.id.main_fragment_layout, Fragment_first, "fist_Fragment");fragmentTransaction.commit();break;case R.id.btn_second:if (null == Fragment_first) {Fragment_Second = new Fragment_Second();}fragmentTransaction = fragmentManager.beginTransaction();fragmentTransaction.replace(R.id.main_fragment_layout, Fragment_Second, "second_Fragment");fragmentTransaction.commit();break;default:break;}}}

Fragment代碼：

package com.tandong.fragment;import android.os.Bundle;import android.support.v4.app.Fragment;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;public class Fragment_first extends Fragment {private View rootView;@Overridepublic View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {if(container==null)   return null;rootView = inflater.inflate(R.layout.fragment_first, container,false);return rootView;}}

原著：http://www.aplesson.com/?p=377