相信大家都有遇到下拉选择这个功能，接下来我把我学习的给大家分享一下。
一、导入依赖
implementation 'com.github.arcadefire:nice-spinner:1.4.4'
二、具体应用
1、接来下就是创建一个xml布局了fragment_restaurant，我个人比较喜欢用constraintlayout约束性布局，我觉得还挺好用的。
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="/apk/res/android"xmlns:app="/apk/res-auto"android:layout_width="fill_parent"android:layout_height="fill_parent"android:orientation="vertical"><LinearLayoutandroid:id="@+id/ll"android:layout_width="match_parent"android:layout_height="wrap_content"android:gravity="center"android:orientation="horizontal"app:layout_constraintTop_toTopOf="parent"><org.angmarch.views.NiceSpinnerandroid:id="@+id/spinner_fruit"android:layout_width="260dp"android:layout_height="80dp"android:textColor="@color/black"android:textSize="36sp"app:layout_constraintRight_toLeftOf="@id/spinner_food"app:layout_constraintTop_toTopOf="parent" /><org.angmarch.views.NiceSpinnerandroid:id="@+id/spinner_food"android:layout_width="420dp"android:layout_height="80dp"android:layout_marginLeft="40dp"android:textColor="@color/black"android:textSize="36sp"app:layout_constraintLeft_toRightOf="@id/spinner_fruit"app:layout_constraintTop_toTopOf="@id/spinner_fruit" /></LinearLayout></androidx.constraintlayout.widget.ConstraintLayout>
二、布局文件写完，就该写具体的应用逻辑了，我们新建一个activity或者一个fragment，这看你自己的使用场景。
我这里就以创建fragment为例了，创建一个RestaurantFragment。具体使用就是将你的列表清单即一个list绑定到控件中，没错，就这么easy，嘻嘻！
public class RestaurantFragment extends Fragment{private List<String> fruitlist = new ArrayList<>();private List<String> foodlist = new ArrayList<>();@Overridepublic View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {View view = inflater.inflate(R.layout.fragment_restaurant, container, false);fruitlist.add("苹果");fruitlist.add("香蕉");fruitlist.add("西瓜");fruitlist.add("葡萄");foodlist.add("红烧肉");foodlist.add("可乐鸡翅");foodlist.add("奥尔良烤鸡");//找到控件NiceSpinner spinnerFruit = (NiceSpinner) view.findViewById(R.id.spinner_fruit);NiceSpinner spinnerFood = (NiceSpinner) view.findViewById(R.id.spinner_food);//设置背景,自定义的背景spinnerFood.setBackgroundResource(R.drawable.style_item);spinnerFruit.setBackgroundResource(R.drawable.style_item);//将数据绑定spinnerFruit.attachDataSource(fruitlist);spinnerFood.attachDataSource(foodlist);spinnerFruit.setOnSpinnerItemSelectedListener(new OnSpinnerItemSelectedListener() {@Overridepublic void onItemSelected(NiceSpinner parent, View view, int position, long id) {Toast.makeText(getActivity(), "你选择标签" + fruitlist.get(position), Toast.LENGTH_SHORT).show();}});spinnerFood.setOnSpinnerItemSelectedListener(new OnSpinnerItemSelectedListener() {@Overridepublic void onItemSelected(NiceSpinner parent, View view, int position, long id) {Toast.makeText(getActivity(), "你选择标签" + foodlist.get(position), Toast.LENGTH_SHORT).show();}});return view;}}
三、第三部就是在drawable里面新建一个xml样式了style_item。
<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="/apk/res/android"><item android:width="300dp" android:height="72dp"><shape android:shape="rectangle"><solid android:color="#ffffffff" /><corners android:radius="6dp" /></shape></item></selector>
ok，这样大功告成了，运行一下看一下吧！注意，里面的list换成你自己的实际数据就行，布局样式也可以换成你自己的。
