自定义Android的Spinner

 自定义Spinner则是和这两个layout有关，ArrayAdapter中初始化的那个layout，是用来渲染spinner被选择的item的样式，而setDropDownResource这个layout，则是弹出框时用的item样式。也就是说，这个spinner使用了两个列表，只不过第一个列表只是显示了一行而已。

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"              android:layout_width="fill_parent"              android:layout_height="fill_parent"              android:padding="10dip">    <ImageView android:id="@+id/icon"               android:src="@drawable/tick"               android:layout_marginRight="10dip"               android:layout_width="wrap_content"               android:layout_height="wrap_content"               android:visibility="invisible"/>    <TextView android:id="@+id/label"              android:layout_width="wrap_content"              android:layout_height="wrap_content"              android:layout_toRightOf="@id/icon"              android:textColor="#000000"              android:textSize="22dip"/></LinearLayout>

public class CustomSpinnerActivity extends Activity {    public Spinner spinner;    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.ch07_custom_spinner);        Resources res = getResources();        CharSequence[] platforms = res.getTextArray(R.array.platforms);        spinner = (Spinner) findViewById(R.id.target);        ArrayAdapter<CharSequence> adapter = new ArrayAdapter<CharSequence>(this, android.R.layout.simple_spinner_item, platforms) {            @Override            public View getDropDownView(int position, View convertView, ViewGroup parent) {                View view = getLayoutInflater().inflate(R.layout.ch07_custom_spinner_item, parent, false);                TextView label = (TextView) view.findViewById(R.id.label);                label.setText(getItem(position));                if (spinner.getSelectedItemPosition() == position) {                    label.setTextColor(getResources().getColor(R.color.selected_fg));                    view.setBackgroundColor(getResources().getColor(R.color.selected_bg));                    view.findViewById(R.id.icon).setVisibility(View.VISIBLE);                }                return view;            }        };        spinner.setAdapter(adapter);    }}