Sample code for back porting Android NumberPicker widget.

NumberPickerWrapper.java

public abstract class NumberPickerWrapper {

    static public NumberPickerWrapper createHolder(View view) {
        NumberPickerWrapper numberPickerWrapper;
        numberPickerWrapper = Build.VERSION.SDK_INT > 10 ? new NumberPickerWrapper_Sdk14()
                : new NumberPickerWrapper_Sdk10();

        numberPickerWrapper.setView(view);
        return numberPickerWrapper;
    }

    public abstract void setView(View view);

    public abstract void setRange(int start, int end);

    public abstract void setValue(int value);

    public abstract int getValue();
}

NumberPickerWrapper_Sdk10.java

public class NumberPickerWrapper_Sdk10 extends NumberPickerWrapper {

    private com.howaboutwe.ui.NumberPicker numberPicker;

    @Override
    public void setView(View view) {
        numberPicker = (com.howaboutwe.ui.NumberPicker) view;
    }

    @Override
    public void setRange(int start, int end) {
        numberPicker.setRange(start, end);
    }

    @Override
    public void setValue(int value) {
        numberPicker.setCurrent(value);
    }

    @Override
    public int getValue() {
        return numberPicker.getCurrent();
    }
}

NumberPickerWrapper_Sdk14.java

public class NumberPickerWrapper_Sdk14 extends NumberPickerWrapper {

    private android.widget.NumberPicker numberPicker;

    @Override
    public void setView(View view) {
        numberPicker = (android.widget.NumberPicker) view;
    }

    @Override
    public void setRange(int start, int end) {
        numberPicker.setMinValue(start);
        numberPicker.setMaxValue(end);
    }

    @Override
    public void setValue(int value) {
        numberPicker.setValue(value);
    }

    @Override
    public int getValue() {
        return numberPicker.getValue();
    }
}