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";
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		setContentView(R.layout.screen_0);
		
		NumberPicker numpicker=(NumberPicker)findViewById(R.id.numpicker);
		numpicker.setPDListener = this;
		
	}	
	@Override
	public void onPickerChangeListener() {
		// TODO Auto-generated method stub
		Log.d(tag, "-----------------onPickerChangeListener---------------------");
	}
}