检索在微调器中拾取的对象

Question

所以我查看了微调api，但它显示我使用AdapterView处理事件，但我从未创建过自适应的。我在string.xml中创建了数组，然后使用Android进行检索:entries= @ array /arrayname

那么，如何在不创建Adapter的情况下检索用户在微调器中拾取的内容？还是我看错了？

Answer 1

谷歌实现AdapterView的意思是，你必须在你的活动上实现它的OnItemSelectedListener接口，例如：

public class SpinnerActivity extends Activity implements AdapterView.OnItemSelectedListener {
    ...

    public void onItemSelected(AdapterView<?> parent, View view, 
            int pos, long id) {
        // An item was selected. You can retrieve the selected item using
        // parent.getItemAtPosition(pos)
    }

    public void onNothingSelected(AdapterView<?> parent) {
        // Another interface callback
    }
}

并且您必须将该微调器的事件侦听器设置为：

Spinner spinner = (Spinner) findViewById(R.id.spinner);
spinner.setOnItemSelectedListener(this);

下面是一个完整的示例：

MainActivity

public class MainActivity extends Activity implements AdapterView.OnItemSelectedListener {

    //Spinner
    private Spinner spinner;
    //The array that will store the spinner items
    private ArrayList<String> list;

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

        //Create the spinner and add its listener
        spinner = (Spinner)findViewById(R.id.spinner);
        spinner.setOnItemSelectedListener(this);

        //Spinner items, stored as a String array
        list = new ArrayList<>();
        list.add("Item 1");
        list.add("Item 2");
        list.add("Item 3");
        list.add("Item 4");

        //To populate the spinner with a list of choices, you need to specify a SpinnerAdapter in your Activity or Fragment
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, list);
        //Set the adapter to the spinner
        spinner.setAdapter(adapter);


    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

        //To Get the selected item:
        //Since the spinner items are stored inside an array
        //we can get the selected item text such as item.get(position)
        Toast.makeText(this, list.get(position), Toast.LENGTH_LONG).show();
    }

activity_main XML布局

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

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

</LinearLayout>