google的NumberPicker

android3.0里新添的控件，如果不用3.0，就用下面的源码，google写的。

代码太长，见附件。
用法，仅供参考：

public class Screen0 extends Activity implements SetPickerDialogListener{private static final String tag="Screen0";@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.screen_0);NumberPicker numpicker=(NumberPicker)findViewById(R.id.numpicker);numpicker.setPDListener = this;}@Overridepublic void onPickerChangeListener() {// TODO Auto-generated method stubLog.d(tag, "-----------------onPickerChangeListener---------------------");}}