RecyclerView 的类似ListView的简单使用
首先，我们要了解什么是RecyclerView，RecyclerView是v7包中的一个新控件。主要是为了替代listview和gridview的使用，可以很好的提高开发的效率和提升内存优化效率。
那么下面介绍的是类似listview多布局的使用，在listview中，我们可以使用多个布局文件item，让布局看起来更加多样化。
那么RecyclerView是如何使用的呢？首先明确的是在eclipse中，有时候使用jar包的代码自动补全方面不怎么完善，这是个深坑。
主要代码如下……
public class TestActivity extends Activity {
@Override
protected void onCreate(Bundle arg0) {
super.onCreate(arg0);
setContentView(R.layout.activity_test_main);
RecyclerView lRecyclerView = (RecyclerView) findViewById(R.id.recylerView);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);//RecyclerView的布局类型
lRecyclerView.setLayoutManager(layoutManager);
ArrayList<ItemType> one = new ArrayList<ItemType>();//数据源
one.add(new ItemType(1,"name1"));
one.add(new ItemType(1,"name2"));
one.add(new ItemType(1,"name3"));
one.add(new ItemType(1,"name4"));
one.add(new ItemType(1,"name5"));
one.add(new ItemType(1,"name6"));
one.add(new ItemType(2,"name7"));
one.add(new ItemType(2,"name8"));
one.add(new ItemType(2,"name9"));
one.add(new ItemType(2,"name10"));
one.add(new ItemType(2,"name11"));
one.add(new ItemType(3,"name12"));
one.add(new ItemType(3,"name13"));
one.add(new ItemType(3,"name14"));
one.add(new ItemType(3,"name15"));
one.add(new ItemType(3,"name16"));
one.add(new ItemType(3,"name17"));
one.add(new ItemType(3,"name18"));
RecyAdapter adapter = new RecyAdapter(one, this);//适配器使用的
lRecyclerView.setAdapter(adapter);
}
class RecyAdapter extends Adapter<RecyViewHolder> {
private List<ItemType> lists;
private Context context;
private int TYPE1 = 1;
private int TYPE2 = 2;
private int TYPE3 = 3;
private LayoutInflater inflater;
public RecyAdapter(List<ItemType> lists, Context context) {
this.lists = lists;
this.context = context;
inflater = LayoutInflater.from(context);
}
@Override
public int getItemCount() {//总共有多少个item数目
return lists.size();
}
@Override
public int getItemViewType(int position) {//item的布局类型
if (lists.get(position).type == TYPE1) {
return TYPE1;
} else if (lists.get(position).type == TYPE2) {
return TYPE2;
} else {
return TYPE3;
}
}
@Override
public void onBindViewHolder(RecyViewHolder arg0, int position) {//绑定数据源 注意坑就在这里，int类型是代表的是第几个……
if (getItemViewType(position)==TYPE1) {
arg0.tv_1.setText(""+lists.get(position).name);
}else if (getItemViewType(position)==TYPE2) {
arg0.tv_name.setText(""+lists.get(position).name);
arg0.iv_2.setBackgroundColor(Color.RED);
}else {
arg0.iv_3.setBackgroundColor(Color.GREEN);
}
}
@Override
public RecyViewHolder onCreateViewHolder(ViewGroup arg0, int types) {//绑定布局 这里也坑，types的类型是代表什么类型的布局
if (types==TYPE1) {
View view = inflater.inflate(R.layout.activity_test_mian_item1, arg0, false);
return new RecyViewHolder(view,types);
}else if (types==TYPE2) {
View view = inflater.inflate(R.layout.activity_test_mian_item2, arg0, false);
return new RecyViewHolder(view,types);
}else {
View view = inflater.inflate(R.layout.activity_test_mian_item3, arg0, false);
return new RecyViewHolder(view,types);
}
}
}
class RecyViewHolder extends ViewHolder {//ViewHolder 好熟悉吧，没错就是缓存用的
public TextView tv_1;
public ImageView iv_2;
public TextView tv_name;
public ImageView iv_3;
private View view;
public RecyViewHolder(View itemView,int type) {
super(itemView);
view = itemView;
if (type==1) {
tv_1 = (TextView) view.findViewById(R.id.tv_1);
}else if (type==2) {
iv_2 = (ImageView) view.findViewById(R.id.iv_2);
tv_name = (TextView) view.findViewById(R.id.tv_name);
}else {
iv_3 = (ImageView) view.findViewById(R.id.iv_3);
}
}
}
public class ItemType {//bean数据结构类型
public ItemType(int type,String name){
this.type = type;
this.name = name;
}
public int type;
public String name;
}
}
主要的布局文件如何下：
R.layout.activity_test_main.xml布局
<?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"
android:orientation="vertical" >
<android.support.v7.widget.RecyclerView
android:id="@+id/recylerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</LinearLayout>
item布局文件如下 R.layout.activity_test_mian_item1.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"
android:orientation="vertical" >
<TextView android:id="@+id/tv_1"
android:layout_width="match_parent"
android:layout_height="48dp"/>
</LinearLayout>
R.layout.activity_test_mian_item2.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"
android:orientation="vertical" >
<ImageView
android:id="@+id/iv_2"
android:layout_width="match_parent"
android:layout_height="20dp"
android:background="#cccccc" />
<TextView
android:id="@+id/tv_name"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
R.layout.activity_test_mian_item3.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"
android:orientation="vertical" >
<ImageView
android:id="@+id/iv_3"
android:layout_width="match_parent"
android:layout_height="20dp"
android:layout_margin="10dp"
android:background="#cccccccc" />
</LinearLayout>
效果图：
跟listview的使用一样，不过就是viewholder变成强制使用了。
