资料

• Android原生TabLayout使用全解析，看这篇就够了
• ViewPager2和Fragment的组合使用

简介

• 没啥就是实现一个简单的多页面和Tab联动的效果吗，使用标题的实现真的是简单又快捷

简单实现

• TabLayout的部分在上一篇已经实现了。
• 这次实现ViewPager2和Fragment

ViewPager2

• 依赖,因为实在moudle_common中依赖所以是api

    //Viewpager2和Recycler，因为ViewPager2内部好像是使用Recyclerview实现的.
    api 'androidx.recyclerview:recyclerview:1.3.0'
    api 'androidx.viewpager2:viewpager2:1.0.0'

• 布局

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.google.android.material.tabs.TabLayout
        app:layout_constraintBottom_toTopOf="@+id/vp_pic"
        android:id="@+id/tab_pic"
        android:layout_width="match_parent"
        android:layout_height="44dp"
        app:tabIndicatorFullWidth="false"
        app:tabSelectedTextColor="@color/purple_200"
        app:tabMinWidth="50dp"
        app:tabTextColor="@color/teal_700"
        app:tabIndicatorColor="@color/teal_200"
        app:tabIndicator="@drawable/pic_manager_layout_underline"
        app:tabTextAppearance="@style/pic_manager_layout_style"
        app:layout_constraintTop_toTopOf="parent">

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="全部" />

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="未上传" />

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="已上传" />

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="上传中" />
    </com.google.android.material.tabs.TabLayout>


    <androidx.viewpager2.widget.ViewPager2
        app:layout_constraintTop_toBottomOf="@+id/tab_pic"
        android:id="@+id/vp_pic"
        android:layout_width="match_parent"
        android:layout_height="0dp"/>

</androidx.constraintlayout.widget.ConstraintLayout>

• 新建一个Fragment

  
  图片.png

public class PicFragment extends Fragment {

    // TODO: Rename parameter arguments, choose names that match
    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    // TODO: Rename and change types of parameters
    private String mParam1;
    private String mParam2;

    public PicFragment() {
        // Required empty public constructor
    }

    /**
     * Use this factory method to create a new instance of
     * this fragment using the provided parameters.
     *
     * @param param1 Parameter 1.
     * @param param2 Parameter 2.
     * @return A new instance of fragment PicFragment.
     */
    // TODO: Rename and change types and number of parameters
    public static PicFragment newInstance(String param1, String param2) {
        PicFragment fragment = new PicFragment();
        Bundle args = new Bundle();
        args.putString(ARG_PARAM1, param1);
        args.putString(ARG_PARAM2, param2);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            mParam1 = getArguments().getString(ARG_PARAM1);
            mParam2 = getArguments().getString(ARG_PARAM2);
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view = inflater.inflate(R.layout.fragment_pic, container, false);
        initView(view);
        return view;
    }

    private void initView(View view) {
        TextView textView = view.findViewById(R.id.tv_name);
        ImageView imageView = view.findViewById(R.id.img);
        textView.setText(mParam1);
    }
}

• 把Fragment的布局优化以下

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".tablayout.fragment.PicFragment">

    <!-- TODO: Update blank fragment layout -->
    <TextView
        android:id="@+id/tv_name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello_blank_fragment"
        app:layout_constraintTop_toTopOf="parent" />
    <ImageView
        android:id="@+id/img"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:src="@drawable/move1"
        app:layout_constraintTop_toBottomOf="@+id/tv_name" />
</androidx.constraintlayout.widget.ConstraintLayout>

• 写ViewPager2的Adapter

public class PicManagerAdapter extends FragmentStateAdapter {

    List<Fragment> fragments = new ArrayList<>();

    public PicManagerAdapter(@NonNull FragmentManager fragmentManager, @NonNull Lifecycle lifecycle, List<Fragment> fragments) {
        super(fragmentManager, lifecycle);
        this.fragments = fragments;
    }

    @NonNull
    @Override
    public Fragment createFragment(int position) {
        return fragments.get(position);
    }

    @Override
    public int getItemCount() {
        return fragments.size();
    }
}

• 去代码中初始化并使用

    private void initViewPager() {
        ViewPager2 viewPager2 = findViewById(R.id.vp_pic);
        PicManagerAdapter adapter = new PicManagerAdapter(getSupportFragmentManager(),getLifecycle(),fragments);
        viewPager2.setAdapter(adapter);

        new TabLayoutMediator(tableLayout, viewPager2, new TabLayoutMediator.TabConfigurationStrategy() {
            @Override
            public void onConfigureTab(@NonNull TabLayout.Tab tab, int position) {
                tab.setText(tabs.get(position));
            }
        }).attach();
    }

    private void initPage() {
        fragments.add(PicFragment.newInstance("全部",""));
        fragments.add(PicFragment.newInstance("未上传",""));
        fragments.add(PicFragment.newInstance("已上传",""));
        fragments.add(PicFragment.newInstance("上传中",""));

        tabs.add("全部");
        tabs.add("未上传");
        tabs.add("已上传");
        tabs.add("上传中");
    }

• 动图GIF来辣~

最简单的流程走完了哈，反正有时间把他完善完善。