Android - 将 Spinner 配置为使用数组

Question

我以以下方式声明我的 Spinner(它非常静态，所以我在 array.xml 中有 2 个字符串数组用于标题和值)

<Spinner
    android:id="@+id/searchCriteria"
    android:entries="@array/searchBy"
    android:entryValues="@array/searchByValues" />

我希望 spinner.getSelectedItem() 返回一个数组 [title, value]但实际上它只返回一个标题字符串。是否无视android:entryValues?我如何从中获得值(value)，而不是标题？是这仅适用于 XML 还是我需要创建适配器并执行此操作以编程方式？

Answer 1

为什么不使用已知类型的对象以编程方式填充您的 ArrayAdapter 并使用它，而不是双数组方法。我已经写了一个类似性质的教程(底部的链接)来做到这一点。基本前提是创建一个 Java 对象数组，告诉微调器，然后直接从微调器类中使用这些对象。在我的示例中，我有一个表示“状态”的对象，其定义如下:

package com.katr.spinnerdemo;

public class State {

// Okay, full acknowledgment that public members are not a good idea, however
// this is a Spinner demo not an exercise in java best practices.
public int id = 0;
public String name = "";
public String abbrev = "";

// A simple constructor for populating our member variables for this tutorial.
public State( int _id, String _name, String _abbrev )
{
    id = _id;
    name = _name;
    abbrev = _abbrev;
}

// The toString method is extremely important to making this class work with a Spinner
// (or ListView) object because this is the method called when it is trying to represent
// this object within the control.  If you do not have a toString() method, you WILL
// get an exception.
public String toString()
{
    return( name + " (" + abbrev + ")" );
}
}

然后您可以使用这些类的数组填充微调器，如下所示:

       // Step 1: Locate our spinner control and save it to the class for convenience
    //         You could get it every time, I'm just being lazy...   :-)
    spinner = (Spinner)this.findViewById(R.id.Spinner01);

    // Step 2: Create and fill an ArrayAdapter with a bunch of "State" objects
    ArrayAdapter spinnerArrayAdapter = new ArrayAdapter(this,
          android.R.layout.simple_spinner_item, new State[] {   
                new State( 1, "Minnesota", "MN" ), 
                new State( 99, "Wisconsin", "WI" ), 
                new State( 53, "Utah", "UT" ), 
                new State( 153, "Texas", "TX" ) 
                });

    // Step 3: Tell the spinner about our adapter
    spinner.setAdapter(spinnerArrayAdapter);  

您可以按如下方式检索所选项目:

State st = (State)spinner.getSelectedItem();

现在您可以使用真正的 Java 类了。如果要在微调器值发生变化时进行拦截，只需实现 OnItemSelectedListener 并添加适当的方法来处理事件。

public void onItemSelected(AdapterView<?> parent, View view, int position, long id) 
{
    // Get the currently selected State object from the spinner
    State st = (State)spinner.getSelectedItem();

    // Now do something with it.
} 

public void onNothingSelected(AdapterView<?> parent ) 
{ 
}

您可以在此处找到整个教程: http://www.katr.com/article_android_spinner01.php