Android实现下拉菜单Spinner效果

Android 中下拉菜单，即如html中的<select>，关键在于调用setDropDownViewResource方法,以XML的方式定义下拉菜单要显示的模样

1.1.activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical"
  tools:context="com.rj141.sb.kongjian.MainActivity"> 

  <LinearLayout
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:textSize="18dp"
      android:text="请选择您最喜欢的水果：" /> 

    <Spinner
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:id="@+id/spinner" />
  </LinearLayout> 

  <TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="18dp"
    android:id="@+id/tv" /> 

</LinearLayout> 

Spinner是下拉列表的组件

1.2.MainActivity.class

public class MainActivity extends AppCompatActivity { 

  private Spinner s;
  String[] data=new String[]{"苹果","雪梨","西瓜","葡萄","橙子","草莓"};
  private TextView tv; 

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main); 

    tv= (TextView) this.findViewById(R.id.tv);
    s= (Spinner) this.findViewById(R.id.spinner);
    s.setAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,data));
    s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
      @Override
      public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        String str=data[position];
        tv.setText("最喜欢的水果是："+str);
      }
      @Override
      public void onNothingSelected(AdapterView<?> parent) {
      }
    });
  }
}
s.setAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,data))；android.R.layout.simple_list_item_1是指安卓自带的下拉列表格式，data是数据源；
s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener()){..}；是下拉列表的监听

效果图：

以上就是本文的全部内容，希望对大家学习掌握Android实现下拉菜单Spinner组件有所帮助。