三十四、Android Spinner控制項之索引值對用法

一、字典表，用來存放索引值對資訊

package com.ljq.activity;

import java.io.Serializable;

@SuppressWarnings("serial")
public class Dict implements Serializable {
private Integer id;
private String text;

public Dict() {
    }

public Dict(Integer id, String text) {
super();
this.id = id;
this.text = text;
    }

public Integer getId() {
return id;
    }

public void setId(Integer id) {
this.id = id;
    }

public String getText() {
return text;
    }

public void setText(String text) {
this.text = text;
    }

/**
     * 為什麼要重寫toString()呢？
     * 
     * 因為適配器在顯示資料的時候，如果傳入適配器的對象不是字串的情況下，直接就使用對象.toString()
*/
    @Override
public String toString() {
return text;
    }

}

           

          

二、activity類，綁定資料、擷取選中的索引值對

package com.ljq.activity;

import java.util.ArrayList;
import java.util.List;

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

public class MainActivity extends Activity {
private Spinner mySpinner;

    @Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        mySpinner = (Spinner) findViewById(R.id.mySpinner);
        List<Dict> dicts = new ArrayList<Dict>();
        dicts.add(new Dict(1, "測試1"));
        dicts.add(new Dict(2, "測試2"));
        dicts.add(new Dict(3, "測試3"));
        dicts.add(new Dict(4, "測試4"));
        ArrayAdapter<Dict> adapter = new ArrayAdapter<Dict>(this,
                android.R.layout.simple_spinner_item, dicts);
        mySpinner.setAdapter(adapter);
        mySpinner.setOnItemSelectedListener(new OnItemSelectedListener(){
public void onItemSelected(AdapterView<?> parent, View view,
int position, long id) {
// 擷取鍵的方法：mySpinner.getSelectedItem().toString()或((Dict)mySpinner.getSelectedItem()).getId()
// 擷取值的方法：((Dict)mySpinner.getSelectedItem()).getText();
                Toast.makeText(MainActivity.this,
                        "鍵:" + mySpinner.getSelectedItem().toString() + "、" + ((Dict) mySpinner.getSelectedItem()).getId() + 
                        "，值:" + ((Dict) mySpinner.getSelectedItem()).getText(),
                        Toast.LENGTH_LONG).show();
            }

public void onNothingSelected(AdapterView<?> parent) {

            }
        });
    }
}

        

           

三、修改main.xml布局檔案

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <Spinner android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/mySpinner"/>
</LinearLayout>

          

           

四、運行結果如下：