安卓对话框之----下拉列表框(Spinner)



        

简单说一下原理：Spinner.getItemAtPosition(Spinner.getSelectedItemPosition());获取下拉列表框的值
 调用setOnItemSelectedListener()方法，处理下拉列表框被选择事件，把AdapterView.OnItemSelectedListener实例作为参数传入

 

1、布局文件：

<RelativeLayout 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: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=".MainActivity" >

    <Spinner
        android:id="@+id/spinner1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true" />

</RelativeLayout>

<RelativeLayout 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: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=".MainActivity" >

    <Spinner
        android:id="@+id/spinner1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true" />

</RelativeLayout>

 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <ImageView
            android:id="@+id/imageView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" />

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

    </LinearLayout>

</LinearLayout>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <ImageView
            android:id="@+id/imageView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" />

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

    </LinearLayout>

</LinearLayout>

 

2、MainActivity中的代码,其中注释的代码自己可以打开看效果:

package com.example.lession16_spinner;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.SimpleAdapter;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends Activity {
    //声明spinner对象
    private Spinner spinner;

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

        //根据id获取对象
        spinner=(Spinner) findViewById(R.id.spinner1);
        //显示的数组
        final String arr[]=new String[]{
                "星期一",
                "星期二",
                "星期三",
                "星期四",
                "星期五",
                "星期六",
                "星期日"
        };

        ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, arr);

        /*List<Map<String,Object>> data=new ArrayList<Map<String,Object>>();
        Map<String,Object> map=new HashMap<String, Object>();
        map.put("logo", R.drawable.ic_launcher);
        map.put("text","xxXx说明操作");

        Map<String, Object> map2=new HashMap<String, Object>();
        map2.put("logo", R.drawable.ic_launcher);
        map2.put("text","xxx说明xdds");

        data.add(map);
        data.add(map2);

        SimpleAdapter simpleAdapter=new SimpleAdapter(this, data, R.layout.activity_item, new String[]{"logo","text"}, new int[]{R.id.imageView1,R.id.textView1});*/
        //设置显示的数据
        spinner.setAdapter(arrayAdapter);
        Toast.makeText(getApplicationContext(), "main Thread"+spinner.getItemIdAtPosition(spinner.getSelectedItemPosition()), Toast.LENGTH_LONG).show();

        //注册事件
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                Spinner spinner=(Spinner) parent;
                Toast.makeText(getApplicationContext(), "xxxx"+spinner.getItemAtPosition(position), Toast.LENGTH_LONG).show();
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                Toast.makeText(getApplicationContext(), "没有改变的处理", Toast.LENGTH_LONG).show();
            }

        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

package com.example.lession16_spinner;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.SimpleAdapter;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends Activity {
	//声明spinner对象
	private Spinner spinner;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		//根据id获取对象
		spinner=(Spinner) findViewById(R.id.spinner1);
		//显示的数组
		final String arr[]=new String[]{
				"星期一",
				"星期二",
				"星期三",
				"星期四",
				"星期五",
				"星期六",
				"星期日"	
		};
		
		ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, arr);
		
		/*List<Map<String,Object>> data=new ArrayList<Map<String,Object>>();
		Map<String,Object> map=new HashMap<String, Object>();
		map.put("logo", R.drawable.ic_launcher);
		map.put("text","xxXx说明操作");
		
		Map<String, Object> map2=new HashMap<String, Object>();
		map2.put("logo", R.drawable.ic_launcher);
		map2.put("text","xxx说明xdds");
		
		data.add(map);
		data.add(map2);
		
		SimpleAdapter simpleAdapter=new SimpleAdapter(this, data, R.layout.activity_item, new String[]{"logo","text"}, new int[]{R.id.imageView1,R.id.textView1});*/
		//设置显示的数据
		spinner.setAdapter(arrayAdapter);
		Toast.makeText(getApplicationContext(), "main Thread"+spinner.getItemIdAtPosition(spinner.getSelectedItemPosition()), Toast.LENGTH_LONG).show();
		
		//注册事件
		spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

			@Override
			public void onItemSelected(AdapterView<?> parent, View view,
					int position, long id) {
				Spinner spinner=(Spinner) parent;
				Toast.makeText(getApplicationContext(), "xxxx"+spinner.getItemAtPosition(position), Toast.LENGTH_LONG).show();
			}

			@Override
			public void onNothingSelected(AdapterView<?> parent) {
				Toast.makeText(getApplicationContext(), "没有改变的处理", Toast.LENGTH_LONG).show();
			}

		});
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

}

效果图：