viewpager2实现fragment的加载

app/build.gradle

@@ -64,4 +64,7 @@ dependencies {
     implementation "androidx.fragment:fragment:$fragment_version"
 
 
+
+
+
 }

app/src/main/java/com/android/activity/HomePageActivity.java

@@ -24,6 +24,7 @@ public class HomePageActivity extends AppCompatActivity implements BottomNavigat
     private FragmentTransaction fragmentTransaction;
 
 
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

app/src/main/java/com/android/activity/LoginActivity.java

@@ -82,6 +82,7 @@ public class LoginActivity extends AppCompatActivity implements LoginListener, V
 
         this.responseData = responseData;
         login();
+        Log.e("responseData",String.valueOf(responseData.getData().getId()));
 
     }
 

app/src/main/java/com/android/activity/adapter/GoodsTypeFSAdapter.java

@@ -0,0 +1,40 @@
+package com.android.activity.adapter;
+
+import android.os.Bundle;
+
+import androidx.annotation.NonNull;
+import androidx.fragment.app.Fragment;
+import androidx.fragment.app.FragmentManager;
+import androidx.lifecycle.Lifecycle;
+import androidx.viewpager2.adapter.FragmentStateAdapter;
+
+import com.android.activity.fragment.GoodsTypeFragment;
+import com.android.bean.Goods;
+import com.android.bean.GoodsType;
+
+import java.util.List;
+
+public class GoodsTypeFSAdapter extends FragmentStateAdapter{
+    private List<GoodsType> goodsTypeList;
+    private List<Fragment> fragmentList;
+
+    public GoodsTypeFSAdapter(@NonNull FragmentManager fragmentManager,
+                              @NonNull Lifecycle lifecycle,
+//                              List<GoodsType> goodsTypeList, List<Goods> goodsList,
+                              List<Fragment> fragmentList){
+        super(fragmentManager, lifecycle);
+        this.fragmentList = fragmentList;
+    }
+
+    @NonNull
+    @Override
+    public Fragment createFragment(int position) {
+
+        return fragmentList.get(position);
+    }
+
+    @Override
+    public int getItemCount() {
+        return fragmentList.size();
+    }
+}

app/src/main/java/com/android/activity/fragment/GoodsTypeFragment.java

@@ -0,0 +1,73 @@
+package com.android.activity.fragment;
+
+import android.os.Bundle;
+
+import androidx.fragment.app.Fragment;
+
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+
+import com.android.R;
+
+/**
+ * A simple {@link Fragment} subclass.
+ * Use the {@link GoodsTypeFragment#newInstance} factory method to
+ * create an instance of this fragment.
+ */
+public class GoodsTypeFragment extends Fragment {
+
+    // TODO: Rename parameter arguments, choose names that match
+    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
+    private static final String ARG_TEXT = "param1";
+
+    View rootView;
+
+    // TODO: Rename and change types of parameters
+    private String mParam1;
+
+    public GoodsTypeFragment() {
+        // Required empty public constructor
+    }
+
+    /**
+     * Use this factory method to create a new instance of
+     * this fragment using the provided parameters.
+     *
+     * @param param1 Parameter 1.
+     * @return A new instance of fragment GoodsTypeFragment.
+     */
+    // TODO: Rename and change types and number of parameters
+    public static GoodsTypeFragment newInstance(String param1) {
+        GoodsTypeFragment fragment = new GoodsTypeFragment();
+        Bundle args = new Bundle();
+        args.putString(ARG_TEXT, param1);
+        fragment.setArguments(args);
+        return fragment;
+    }
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        if (getArguments() != null) {
+            mParam1 = getArguments().getString(ARG_TEXT);
+        }
+    }
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        // Inflate the layout for this fragment
+
+        if(rootView == null)
+        rootView = inflater.inflate(R.layout.fragment_goods_type, container, false);
+        initView();
+        return rootView;
+    }
+
+    private void initView() {
+        TextView view = rootView.findViewById(R.id.tv_goods);
+        view.setText(mParam1);
+    }
+}

app/src/main/java/com/android/activity/fragment/HomePageFragment.java

@@ -7,6 +7,7 @@ import androidx.annotation.Nullable;
 import androidx.fragment.app.Fragment;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
+import androidx.viewpager2.widget.ViewPager2;
 
 import android.util.Log;
 import android.view.LayoutInflater;
@@ -17,11 +18,15 @@ import android.widget.Button;
 
 import com.android.R;
 import com.android.activity.adapter.GoodsTypeAdapter;
+import com.android.activity.adapter.GoodsTypeFSAdapter;
 import com.android.bean.GoodsType;
 import com.android.bean.ResponseData;
 import com.android.model.goods.GoodsListener;
 import com.android.model.goods.GoodsModelimpl;
+import com.google.android.material.tabs.TabLayout;
+import com.google.android.material.tabs.TabLayoutMediator;
 
+import java.util.ArrayList;
 import java.util.List;
 
 /**
@@ -34,9 +39,12 @@ public class HomePageFragment extends Fragment implements View.OnClickListener,
     private Button button;
     private GoodsModelimpl goodsModelimpl;
     private List<GoodsType> goodsTypeList;
-    private GoodsTypeAdapter goodsTypeAdapter = null;
+//    private GoodsTypeAdapter goodsTypeAdapter = null;
-    private RecyclerView recyclerView;
+//    private RecyclerView recyclerView;
     private View rootView;
+    private GoodsTypeFSAdapter goodsTypeFSAdapter;
+
+    private ViewPager2 viewPager;
 
 
 
@@ -78,19 +86,34 @@ public class HomePageFragment extends Fragment implements View.OnClickListener,
     @Override
     public void onGetAllGoodsType(ResponseData<List<GoodsType>> responseData) {
         this.goodsTypeList = responseData.getData();
+        this.goodsTypeList.add(new GoodsType(0,"全部"));
+
         initRecyclerview();
 
 
     }
 
     private void initRecyclerview() {
-        recyclerView = rootView.findViewById(R.id.lv_goodsType_list);
+        viewPager = rootView.findViewById(R.id.view_pager);
+
+//        goodsTypeAdapter = new GoodsTypeAdapter(goodsTypeList,context,R.layout.list_good_stype_item);
+//        viewPager.setAdapter(goodsTypeAdapter);
+
+
+        ArrayList<Fragment> fragments = new ArrayList<>();
+        for (int i = 0; i < goodsTypeList.size(); i++) {
+            fragments.add(GoodsTypeFragment.newInstance(goodsTypeList.get(i).getType()));
+        }
+
+
 
-        goodsTypeAdapter = new GoodsTypeAdapter(goodsTypeList,context,R.layout.list_good_stype_item);
+        goodsTypeFSAdapter = new GoodsTypeFSAdapter(getActivity().getSupportFragmentManager(), getLifecycle(),fragments);
+        viewPager.setAdapter(goodsTypeFSAdapter);
+                //把TabLayout（选项卡布局）和ViewPager2绑定在一起。特别说明一下，下面这行代码是官方给的，特别好使。
+        TabLayout tablayout = rootView.findViewById(R.id.tabLayout);
+        new TabLayoutMediator(tablayout, viewPager,
+                (tab, position) -> tab.setText(goodsTypeList.get(position).getType())).attach();
 
-        LinearLayoutManager llm = new LinearLayoutManager(context);
-        recyclerView.setLayoutManager(llm);
-        recyclerView.setAdapter(goodsTypeAdapter);
     }
 
     @Override

app/src/main/java/com/android/bean/GoodsType.java

@@ -4,6 +4,14 @@ public class GoodsType {
     private Integer id;
     private String type;
 
+    public GoodsType() {
+    }
+
+    public GoodsType(Integer id, String type) {
+        this.id = id;
+        this.type = type;
+    }
+
     public Integer getId() {
         return id;
     }

app/src/main/res/layout/fragment_goods_type.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<FrameLayout 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"
+    tools:context=".activity.fragment.GoodsTypeFragment">
+
+    <!-- TODO: Update blank fragment layout -->
+    <TextView
+        android:id="@+id/tv_goods"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:text="@string/hello_blank_fragment" />
+
+</FrameLayout>

app/src/main/res/layout/fragment_home_page.xml

@@ -1,15 +1,24 @@
 <?xml version="1.0" encoding="utf-8"?>
 <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     tools:context=".activity.fragment.HomePageFragment">
 
-    <androidx.recyclerview.widget.RecyclerView
+
-        android:id="@+id/lv_goodsType_list"
+    <com.google.android.material.tabs.TabLayout
-        android:layout_width="wrap_content"
+        android:id="@+id/tabLayout"
+        android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:isScrollContainer="true"/>
+        app:tabMode="scrollable"
+    />
+
+    <androidx.viewpager2.widget.ViewPager2
+        android:id="@+id/view_pager"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        />
 
 
 

app/src/main/res/layout/fragment_shop_page.xml

@@ -3,7 +3,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".activity.fragment.ShopPageFragment">
+    tools:context=".activity.fragment.ShopCarPageFragment">
 
     <!-- TODO: Update blank fragment layout -->
     <TextView

app/src/main/res/layout/list_good_stype_item.xml

@@ -8,6 +8,7 @@
         android:id="@+id/tv_goods_type_item"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:layout_gravity="center"
         android:text="商品"
         />