android复习路之RecyclerView简单的应用

之前接触了RecyclerView学写了一个简单的demo效果就是实现美团顶部的侧滑效果，今天就是只是简单的实现效果，不深入理解，明天深入理解RecyclerView，各种变换和操作。MainActivity代码：

public class MainActivity extends AppCompatActivity {
private RecyclerView rv;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
rv = (RecyclerView) findViewById(R.id.rv);
initdata();
}

private void initdata() {

/*
初始化数据
*/
List<Integer> datas = new ArrayList<>();
for (int i = 0; i < 20; i++) {
Resources rs = getResources();
datas.add(rs.getIdentifier("ic_launcher", "mipmap", getPackageName()));
}

/*
用来确定每一个item如何进行排列摆放
LinearLayoutManager 相当于ListView的效果
GridLayoutManager相当于GridView的效果
StaggeredGridLayoutManager 瀑布流
*/
rv.setLayoutManager(new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.HORIZONTAL));
rv.addItemDecoration(new RecyclerView.ItemDecoration() {
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
//outRect.left = 10;
//outRect.top = 10;
//outRect.top = 10;
}
});
rv.setAdapter(new LinearRecyclerView(this,datas));
}
}

LinearRecyclerView类代码：

public  class LinearRecyclerView extends RecyclerView.Adapter<LinearRecyclerView.MyViewHolder>{
private Context context;
private List<Integer> datas;
public  LinearRecyclerView(Context context,List<Integer>datas){
this.context=context;
this.datas=datas;
}

@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View contentView =LayoutInflater.from(context).inflate(R.layout.item_layout,parent,false);
MyViewHolder viewHolder=new MyViewHolder(contentView);
return viewHolder;
}

@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
holder.imageView.setImageResource(datas.get(position));
holder.textView.setText("分类"+position);
}

@Override
public int getItemCount() {

return datas==null?0:datas.size();
}

public class MyViewHolder extends RecyclerView.ViewHolder{
private ImageView imageView;
private TextView textView;
public MyViewHolder(View itemView) {
super(itemView);
imageView= (ImageView) itemView.findViewById(R.id.img);
textView= (TextView) itemView.findViewById(R.id.tv);
}
}
}

主布局xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.zobject.linearrecyclerview.MainActivity">

<android.support.v7.widget.RecyclerView
android:layout_height="200dp"
android:layout_width="match_parent"
android:id="@+id/rv"
>

</android.support.v7.widget.RecyclerView>

</RelativeLayout>

item布局xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="70dp"
android:layout_height="match_parent"
android:orientation="vertical"
>
<ImageView
android:id="@+id/img"
android:layout_gravity="center"
android:layout_width="60dp"
android:layout_height="75dp"
>
</ImageView>>
<TextView
android:id="@+id/tv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:textColor="#000000"
android:text="nicaicai"
>

</TextView>

</LinearLayout>

代码没什么说的都是基本的模版代码，方便以后查看，下面是效果图：