Android下拉列表框Spinner使用方法详解

<?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"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.administrator.myapplication.MainActivity">
 
    <Spinner
        android:id="@+id/spinner"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>
 
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/tvCateItem"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="34px" />

package com.example.administrator.myapplication;
 
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;
 
public class MainActivity extends AppCompatActivity {
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // 获取控件
        Spinner spinner = (Spinner) findViewById(R.id.spinner);
        // 要添加到下拉列表框中的数据
        String[] array = new String[]{"唐僧", "孙悟空", "猪八戒", "沙僧", "小白龙"};
        // 创建适配器
        final ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(MainActivity.this, R.layout.spinner_item, array);
        dataAdapter.setDropDownViewResource(R.layout.spinner_item);
        // 为下拉列表框设置适配器
        spinner.setAdapter(dataAdapter);
 
        // spinner的选项被选中的监听事件
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                String value = dataAdapter.getItem(position).toString();// 获取被选中的下拉列表框项的值
                Toast.makeText(MainActivity.this, "你选中了：" + value, Toast.LENGTH_SHORT).show();
            }
 
            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                // 没有任何被选中的处理事件
            }
        });
    }
}