package com.example.xh.twostylefragment; import andROId.content.Intent; import android.os.Bundle; import android.support.v4.app.FragmentTransaction; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button;   public class MainActivity extends AppCompatActivity implements View.OnClickListener{   //定义5个fragment   PRivate MyFragment F1;   private MyFragment2 f2;   private MyFragment3 f3;   private MyFragment4 f4;   private MyFragment5 f5;   //定义底部5个按钮   private Button foot1;   private Button foot2;   private Button foot3;   private Button foot4;   private Button foot5;   int i = 0;   @override   protected void onCreate(Bundle savedInstancestate) {     suPEr.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);       foot1 = (Button) findViewById(R.id.BTn1);//注册按钮     foot2 = (Button) findViewById(R.id.btn2);     foot3 = (Button) findViewById(R.id.btn3);     foot4 = (Button) findViewById(R.id.btn4);     foot5 = (Button) findViewById(R.id.btn5);     foot1.setOnClickListener(this);//对按钮设置监听     foot2.setOnClickListener(this);     foot3.setOnClickListener(this);     foot4.setOnClickListener(this);     foot5.setOnClickListener(this);     //第一次初始化首页默认显示第一个fragment     initFragment1();   }     //显示第一个fragment   private void initFragment1(){     //开启事务，fragment的控制是由事务来实现的     FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();       //第一种方式（add），初始化fragment并添加到事务中，如果为null就new一个     if(f1 == null){       f1 = new MyFragment();       transaction.add(R.id.main_frame_layout, f1);     }     //隐藏所有fragment     hideFragment(transaction);     //显示需要显示的fragment     transaction.show(f1);       //第二种方式(replace)，初始化fragment //    if(f1 == null){ //      f1 = new MyFragment("首页"); //    } //    transaction.replace(R.id.main_frame_layout, f1);       //提交事务     transaction.COMmit();   }     //显示第二个fragment   private void initFragment2(){     FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();       if(f2 == null){       f2 = new MyFragment2();       transaction.add(R.id.main_frame_layout,f2);     }     hideFragment(transaction);     transaction.show(f2);   //    if(f2 == null) { //      f2 = new MyFragment("分类"); //    } //    transaction.replace(R.id.main_frame_layout, f2);       transaction.commit();   }     //显示第三个fragment   private void initFragment3(){     FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();       if(f3 == null){       f3 = new MyFragment3();       transaction.add(R.id.main_frame_layout,f3);     }     hideFragment(transaction);     transaction.show(f3);   //    if(f3 == null) { //      f3 = new MyFragment("发现"); //    } //    transaction.replace(R.id.main_frame_layout, f3);       transaction.commit();   }   private void initFragment4(){     FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();       if(f4 == null){       f4 = new MyFragment4();       transaction.add(R.id.main_frame_layout,f4);     }     hideFragment(transaction);     transaction.show(f4);   //    if(f4 == null) { //      f4 = new MyFragment("购物车"); //    } //    transaction.replace(R.id.main_frame_layout, f4);       transaction.commit();   }   private void initFragment5(){     FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();       if(f5 == null){       f5 = new MyFragment5();       transaction.add(R.id.main_frame_layout,f5);     }     hideFragment(transaction);     transaction.show(f5);   //    if(f5 == null) { //      f5 = new MyFragment("我的); //    } //    transaction.replace(R.id.main_frame_layout, f5);       transaction.commit();   }     //隐藏所有的fragment   private void hideFragment(FragmentTransaction transaction){     if(f1 != null){       transaction.hide(f1);     }     if(f2 != null){       transaction.hide(f2);     }     if(f3 != null){       transaction.hide(f3);     }     if(f4 != null){       transaction.hide(f4);     }     if(f5 != null){       transaction.hide(f5);     }   }     @Override   public void onClick(View v) {//点击哪个按钮就显示哪个fragment;     if(v == foot1){       initFragment1();     }else if(v == foot2){       initFragment2();     }else if(v == foot3){       initFragment3();     }else if(v == foot4){       initFragment4();     }else if(v == foot5){       initFragment5();     }   } }

 package com.example.xh.twostylefragment;       import android.os.Bundle;     import android.support.v4.app.Fragment;     import android.view.LayoutInflater;     import android.view.View;     import android.view.ViewGroup;   /**  * Created by Administrator on 2016/7/8.  */ public class MyFragment4 extends Fragment {   @Override   public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {     View view = LayoutInflater.From(getActivity()).inflate(R.layout.shoppingcar,container,false);//用view保存shoppingcar.xML布局，大家可以     return view;                                         //自己创建一个xml.   }   }