引用的改變，implementation'com.android.support:recyclerview-v7:28.0.0'

在學習第二行代碼中，RecuclerView的使用中，遇到這樣的問題：

1-1

媽耶，直接暈了。一個子項充滿了一個屏幕，在我3天的度娘中，還好有一樣的同學，

解決辦法，問題出現(xiàn)在子項的布局

1-2

就是這個地方布局有問題。改成wrap_content就好了。

源碼：

```

Adapter//適配器

package com.example.recycler_view_test;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.ImageView;

import android.widget.TextView;

import androidx.annotation.NonNull;

import androidx.recyclerview.widget.RecyclerView;

import java.util.List;

public class Fruit_Adapterextends RecyclerView.Adapter {

private ListmfruitList;

static class ViewHolderextends RecyclerView.ViewHolder {//繼承RecyclerView.ViewHolder? 緩存最外層的布局數(shù)據

? ? ? ? private ImageViewimageView;

private TextViewtextView;

public ViewHolder(View itemView) {

super(itemView);

imageView=(ImageView)itemView.findViewById(R.id.fruit_image);

textView=(TextView)itemView.findViewById(R.id.fruit_name);

}

}

public? Fruit_Adapter (List fruitList){

mfruitList=fruitList;//獲取數(shù)據源

? ? }

@Override

? ? public ViewHolder onCreateViewHolder( ViewGroup parent,int viewType) {

View view= LayoutInflater.from(parent.getContext()).inflate(R.layout.fruit,parent,false);

ViewHolder viewHolder=new ViewHolder(view);

return viewHolder;

}

@Override

? ? public void onBindViewHolder( ViewHolder holder,int position) {

Fruit fruit=mfruitList.get(position);

holder.imageView.setImageResource(fruit.getImage_id());

holder.textView.setText(fruit.getName());

}

@Override

? ? public int getItemCount() {

return mfruitList==null?0:mfruitList.size();

}

}

```

```

mainactivity?

package com.example.recycler_view_test;

import androidx.appcompat.app.AppCompatActivity;

import androidx.recyclerview.widget.LinearLayoutManager;

import androidx.recyclerview.widget.RecyclerView;

import android.os.Bundle;

import java.util.ArrayList;

import java.util.List;

public class MainActivityextends AppCompatActivity {

private ListmfruitList;

@Override

? ? protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

mfruitList=getFruitList();

RecyclerView recyclerView=(RecyclerView)findViewById(R.id.recyclerview);

LinearLayoutManager llmanager=new LinearLayoutManager(MainActivity.this);

recyclerView.setLayoutManager(llmanager);

Fruit_Adapter fruit_adapter=new Fruit_Adapter(mfruitList);

recyclerView.setAdapter(fruit_adapter);

}

public List getFruitList() {

List fruitList=new ArrayList<>();

Fruit fruit=new Fruit("apple",R.drawable.ic_launcher_background);

fruitList.add(fruit);

Fruit fruit1=new Fruit("apple1",R.drawable.ic_launcher_background);

fruitList.add(fruit1);

Fruit fruit2=new Fruit("apple2",R.drawable.ic_launcher_background);

fruitList.add(fruit2);

Fruit fruit3=new Fruit("apple3",R.drawable.ic_launcher_background);

fruitList.add(fruit3);

Fruit fruit4=new Fruit("apple4",R.drawable.ic_launcher_background);

fruitList.add(fruit4);

Fruit fruit5=new Fruit("apple5",R.drawable.ic_launcher_background);

fruitList.add(fruit5);

Fruit fruit6=new Fruit("apple6",R.drawable.ic_launcher_background);

fruitList.add(fruit6);

Fruit fruit7=new Fruit("apple7",R.drawable.ic_launcher_background);

fruitList.add(fruit7);

Fruit fruit8=new Fruit("apple8",R.drawable.ic_launcher_background);

fruitList.add(fruit8);

Fruit fruit9=new Fruit("apple9",R.drawable.ic_launcher_background);

fruitList.add(fruit9);

Fruit fruit10=new Fruit("apple10",R.drawable.ic_launcher_background);

fruitList.add(fruit10);

Fruit fruit11=new Fruit("apple11",R.drawable.ic_launcher_background);

fruitList.add(fruit11);

return fruitList;

}

}

```