【Android -- 开源库】BRVAH 的基本使用

一、简介

BRVAH 是一个强大的 RecyclerAdapter 框架，它能节约开发者大量的开发时间，集成了大部分列表常用需求解决方案。

二、框架引入

1. 在 build.gradle(Project:XXXX) 的 repositories 添加:

allprojects {repositories {...maven { url "https://jitpack.io"}}
}

2. 在 build.gradle(Module:app) 的 dependencies 添加:

dependencies {implementation 'com.github.CymChad:BaseRecyclerViewAdapterHelper:2.9.30'
}

三、使用 Adapter

1. 效果图

2. HomeBean.java

/*** Created on 2019/11/28 9:30** @author Gong Youqiang*/
public class HomeBean {private String name;private int iconId;public HomeBean(String name, int iconId) {this.name = name;this.iconId = iconId;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getIconId() {return iconId;}public void setIconId(int iconId) {this.iconId = iconId;}
}

2. HomeAdapter.java

/*** Created on 2019/11/28 9:31** @author Gong Youqiang*/
public class HomeAdapter extends BaseQuickAdapter<HomeBean, BaseViewHolder> {public HomeAdapter(int layoutResId, @Nullable List<HomeBean> data) {super(layoutResId, data);}@Overrideprotected void convert(BaseViewHolder helper, HomeBean item) {helper.setText(R.id.tv_name,item.getName());helper.setImageResource(R.id.iv_img,item.getIconId());CardView cardView = helper.getView(R.id.card_view);helper.addOnClickListener(R.id.card_view);}
}

3. item_home.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardViewxmlns:android="http://schemas.android.com/apk/res/android"xmlns:card_view="http://schemas.android.com/apk/res-auto"android:id="@+id/card_view"android:layout_width="120dp"android:layout_height="120dp"android:layout_gravity="center"android:foreground="?android:attr/selectableItemBackground"card_view:cardBackgroundColor="@color/white"card_view:cardCornerRadius="4dp"card_view:cardElevation="2dp"card_view:cardUseCompatPadding="true"><LinearLayoutandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_gravity="center"android:gravity="center"android:orientation="vertical"><ImageViewandroid:id="@+id/iv_img"android:layout_width="90dp"android:layout_height="90dp"android:src="@mipmap/ic_launcher"/><TextViewandroid:id="@+id/tv_name"android:layout_width="wrap_content"android:layout_height="wrap_content"android:textSize="16sp"android:text="android"android:textColor="@color/black"/></LinearLayout>
</androidx.cardview.widget.CardView>

4. activity_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"><androidx.recyclerview.widget.RecyclerViewandroid:id="@+id/recyclerView"android:layout_width="match_parent"android:layout_height="match_parent"/>
</LinearLayout>

5. top_view.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"android:orientation="vertical" android:layout_width="match_parent"android:layout_height="match_parent"><ImageViewandroid:id="@+id/imageView"android:layout_width="match_parent"android:layout_height="wrap_content"app:srcCompat="@mipmap/ic_home_bg" />
</LinearLayout>

6. Activity

public class LayoutActivity extends AppCompatActivity {@BindView(R.id.recyclerView)RecyclerView mRecyclerView;HomeAdapter mAdapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_layout);ButterKnife.bind(this);initAdapter();}private void initAdapter() {mAdapter = new HomeAdapter(R.layout.item_home,getHomeItem());mAdapter.openLoadAnimation();View top = getLayoutInflater().inflate(R.layout.top_view, (ViewGroup) mRecyclerView.getParent(), false);mAdapter.addHeaderView(top);mAdapter.setOnItemChildClickListener(new BaseQuickAdapter.OnItemChildClickListener() {@Overridepublic void onItemChildClick(BaseQuickAdapter adapter, View view, int position) {Toast.makeText(LayoutActivity.this,"click"+position,Toast.LENGTH_SHORT).show();}});mRecyclerView.setLayoutManager(new GridLayoutManager(LayoutActivity.this,3));mRecyclerView.setAdapter(mAdapter);}private List<HomeBean> getHomeItem() {return Arrays.asList(new HomeBean("android",R.mipmap.ic_launcher),new HomeBean("ios",R.mipmap.ic_launcher),new HomeBean("haha",R.mipmap.ic_launcher),new HomeBean("andnnroid",R.mipmap.ic_launcher),new HomeBean("dddd",R.mipmap.ic_launcher),new HomeBean("dddd",R.mipmap.ic_launcher),new HomeBean("dddd",R.mipmap.ic_launcher),new HomeBean("dddd",R.mipmap.ic_launcher),new HomeBean("dddd",R.mipmap.ic_launcher),new HomeBean("dddd",R.mipmap.ic_launcher),new HomeBean("dddd",R.mipmap.ic_launcher));}}

四、常见问题

为什么有数据不显示？
请检查一下你的RecyclerView是否设置了LayoutManager。

为什么有10条数据，只显示1条？
请检查一下item的布局最外层的Layout是不是layout_height设置了match_parent.

数据状态错乱
这个问题无论是RecyclerView还是ListView不做处理都会出现问题，这个本质上是由于布局重用机制导致的，解决办法是通过数据状态来控制控件的状态，一定要设置状态无论什么状态，if和else是少不了的，如下代码：

  if（entity.isCheck）{checkBox.isChecked(true);} else {checkBox.isChecked(false);}