Custom Number Field Blackberry

Number Field yang di maksud disini adalah field yang hanya menerima inputan berupa angka (0-9). Code-nya sebenarnya hampir sama dengan Custom EditField yang pernah saya tulis, tapi ada beberapa perbedaan.

Berikut code-nya:

import net.rim.device.api.system.Characters;
import net.rim.device.api.system.Display;
import net.rim.device.api.ui.Color;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.Font;
import net.rim.device.api.ui.Graphics;
import net.rim.device.api.ui.Manager;
import net.rim.device.api.ui.component.BasicEditField;
  
public class NumberFieldCustom extends Manager {
      
    private final static int DEFAULT_LEFT_MARGIN = 1;
    private final static int DEFAULT_RIGHT_MARGIN = 1;
    private final static int DEFAULT_TOP_MARGIN = 3;
    private final static int DEFAULT_BOTTOM_MARGIN = 1;
       
    private final static int DEFAULT_LEFT_PADDING = 5;
    private final static int DEFAULT_RIGHT_PADDING = 5;
    private final static int DEFAULT_TOP_PADDING = 3;
    private final static int DEFAULT_BOTTOM_PADDING = 3;
       
    private int topMargin = DEFAULT_TOP_MARGIN;
    private int bottomMargin = DEFAULT_BOTTOM_MARGIN;
    private int leftMargin = DEFAULT_LEFT_MARGIN;
    private int rightMargin = DEFAULT_RIGHT_MARGIN;
       
    private int topPadding = DEFAULT_TOP_PADDING;
    private int bottomPadding = DEFAULT_BOTTOM_PADDING;
    private int leftPadding = DEFAULT_LEFT_PADDING;
    private int rightPadding = DEFAULT_RIGHT_PADDING;
       
    private int totalHorizontalEmptySpace = leftMargin + leftPadding + rightPadding + rightMargin;
    private int totalVerticalEmptySpace = topMargin + topPadding + bottomPadding + bottomMargin;
       
    private int minHeight = 21 + totalVerticalEmptySpace;
    private int width;
    private int height = minHeight;
    private int text_colour = 0xFF0000;
    private int border_color = 0x000066;
    private int background_color = 0xFFFF99;
    private String label = "";
    private Font headingFont = getFont().derive(Font.PLAIN, 20);
    private BasicEditField editField;
      
    public NumberFieldCustom (){
        super(0);
        this.label = "";
        this.width = Display.getWidth()/2;
        editField = new BasicEditField(BasicEditField.FILTER_NUMERIC);
        add(editField);
    }
      
    public NumberFieldCustom (int panjang){
        super(0);
        this.label = "";
        this.width = panjang;
        editField = new BasicEditField(BasicEditField.FILTER_NUMERIC);
        add(editField);
    }
       
    protected void sublayout(int width, int height)
    {
        Field field = getField(0);
        layoutChild(field, this.width - totalHorizontalEmptySpace , this.height - totalVerticalEmptySpace);
        setPositionChild(field, leftMargin+leftPadding, topMargin+topPadding);
        setExtent(this.width, this.height);
    }   
       
    protected void paint(Graphics graphics){   
        graphics.setColor(border_color);
        graphics.drawRoundRect(leftMargin, topMargin, width - (leftMargin+rightMargin), height - (topMargin+bottomMargin), 7, 7);
        graphics.setColor(background_color);
        graphics.fillRoundRect(leftMargin+1, topMargin+1, (width - (leftMargin+rightMargin))-2, (height- (topMargin+bottomMargin))-2, 7, 7);
          
        graphics.setColor(Color.BLACK);
        if(headingFont!=null){
            setFont(headingFont);
            graphics.drawText(label, 2, 10);
        }else{
            graphics.drawText(label, 2, 7);
        }
          
        graphics.setColor(text_colour);
        BasicEditField ef = (BasicEditField)getField(0);
        String entireText = ef.getText();
          
        boolean longText = false;
        String textToDraw = "";
        Font font = headingFont;
        int availableWidth = width - totalHorizontalEmptySpace;
        if (font.getAdvance(entireText) <= availableWidth)
        {
            textToDraw = entireText;
        }
        else
        {
            int endIndex = entireText.length();
            for (int beginIndex = 1; beginIndex < endIndex; beginIndex++)
            {
                textToDraw = entireText.substring(beginIndex);
                if (font.getAdvance(textToDraw) <= availableWidth)
                {
                    longText = true;
                    break;
                }
            }
        }
          
        if (longText == true)
        {      
            ef.setText(textToDraw);        
            super.paint(graphics);
            ef.setText(entireText);
        }
        else
        {
            super.paint(graphics);
        }
           
    }
       
    public int getPreferredWidth(){
        return width;
    }
       
    public int getPreferredHeight(){
        return height;
    }
       
    protected boolean keyChar(char ch, int status, int time){      
       if (ch == Characters.ENTER)
       {
            return true;
       }   
       else
       {
            return super.keyChar(ch, status, time);
       }
    }
     
    protected void onUnfocus() {
       super.onUnfocus();
    }
     
    protected void onFocus(int direction) {
       super.onFocus(direction);
    }
    
    protected void drawFocus(Graphics graphics, boolean on) {
       super.drawFocus(graphics, on);
    }
  
    public String getText(){
       return ((BasicEditField) getField(0)).getText();
    }
           
    public void setText(final String text){
       ((BasicEditField)getField(0)).setText(text);
    }
}