以最后一项为链接的自定义微调器

Question

我想要一个包含最后一个Item的Spinner作为"添加更多项目"当我点击它时，我可以添加下一个项目。我添加的项目应该显示在微调器列表中，并且最后一个项目与"添加更多项目"相同。。我尝试过使用Adapter，但如何将最后一个元素保留为"添加更多项目"

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            if (position == spinner.getItemIdAtPosition(spinner.getCount()))
                // my code for adding item to list using Adapter
            else
                // spinner.setSelection();
        }

我写错什么了吗？？有什么帮助吗？？。。谢谢

Answer 1

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
           <Spinner
            android:id="@+id/spinner1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:dropDownVerticalOffset="2dp"
            android:dropDownWidth="500sp"
            android:spinnerMode="dropdown" />

    </RelativeLayout>

MainActivity.java:

public class MainActivity extends Activity {
    private Spinner spinner;
    ArrayAdapter<String> adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final ArrayList<String> data = new ArrayList<String>();
        for (int i = 0; i < 5; i++) {
            data.add("item " + i);
        }
        data.add("Add New Item");
        adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, data);
        spinner = (Spinner) findViewById(R.id.spinner1);
        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                tv.setText(spinner.getSelectedItem().toString());
                if (spinner.getSelectedItem().toString().equals("Add New Item")) {
                    data.remove(position);
                    data.add(position, "item " + position);
                    data.add((position + 1), "Add New Item");
                    updateAdapter(data);
                    Toast.makeText(getApplicationContext(), "item " + position,
                            Toast.LENGTH_LONG).show();
                }
            }
            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                // TODO Auto-generated method stub
            }
        });
    }
    public void updateAdapter(ArrayList<String> data) {
        adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1,
                data);
        adapter.notifyDataSetChanged();
    }
}