Custom Image Button in Blackberry

1. final imagebutton img_btn = new imagebutton("",Field.FOCUSABLE, "normal_image.png","mouse_over_image.png", 0x9cbe95);
   
   
   
   
   //Image Button Class
   
   
   import net.rim.device.api.ui.*;
2. import net.rim.device.api.system.*;
4. public class imagebutton extends Field {
5.        
6.     private String _label;
7.     private int _labelHeight;
8.     private int _labelWidth;
9.     private Font _font;
10.    
11.     private Bitmap _currentPicture;
12.     private Bitmap _onPicture;
13.     private Bitmap _offPicture;
14.     int color;
15.    
16.     public imagebutton(String text, long style ,String img, String img_hvr, int color){
17.         super(style);
18.        
20.         _offPicture = Bitmap.getBitmapResource(img);
21.         _onPicture = Bitmap.getBitmapResource(img_hvr);
22.        
23.         _font = getFont();
24.         _label = text;
25.         _labelHeight = _onPicture.getHeight();  
26.         _labelWidth = _onPicture.getWidth();
27.        
28.         this.color = color;
29.        
30.         _currentPicture = _offPicture;
31.     }
32.    
33.     /**
34.      * @return The text on the button
35.      */
36.     String getText(){
37.         return _label;
38.     }
39.    
40.     /**
41.      * Field implementation.
42.      * @see net.rim.device.api.ui.Field#getPreferredHeight()
43.      */
44.     public int getPreferredHeight(){
45.         return _labelHeight;
46.     }
48.     /**
49.      * Field implementation.
50.      * @see net.rim.device.api.ui.Field#getPreferredWidth()
51.      */
52.     public int getPreferredWidth(){
53.         return _labelWidth;
54.     }
55.    
56.     /**
57.      * Field implementation.  Changes the picture when focus is gained.
58.      * @see net.rim.device.api.ui.Field#onFocus(int)
59.      */
60.     protected void onFocus(int direction) {
61.         _currentPicture = _onPicture;
62.         invalidate();
63.     }
65.     /**
66.      * Field implementation.  Changes picture back when focus is lost.
67.      * @see net.rim.device.api.ui.Field#onUnfocus()
68.      */
69.     protected void onUnfocus() {
70.         _currentPicture = _offPicture;
71.         invalidate();
72.     }
73.    
74.     /**
75.      * Field implementation.  
76.      * @see net.rim.device.api.ui.Field#drawFocus(Graphics, boolean)
77.      */
78.     protected void drawFocus(Graphics graphics, boolean on) {
79.         // Do nothing
80.     }
81.    
82.     /**
83.      * Field implementation.
84.      * @see net.rim.device.api.ui.Field#layout(int, int)
85.      */
86.     protected void layout(int width, int height) {
87.         setExtent(Math.min( width, getPreferredWidth()),
88.         Math.min( height, getPreferredHeight()));
89.     }
91.     /**
92.      * Field implementation.
93.      * @see net.rim.device.api.ui.Field#paint(Graphics)
94.      */
95.     protected void paint(Graphics graphics){      
96.         // First draw the background colour and picture
97.         graphics.setColor(this.color);
98.         graphics.fillRect(0, 0, getWidth(), getHeight());
99.         graphics.drawBitmap(0, 0, getWidth(), getHeight(), _currentPicture, 0, 0);
100.        
101.         // Then draw the text
102.         graphics.setColor(Color.BLACK);
103.         graphics.setFont(_font);
104.         graphics.drawText(_label, 4, 2,
105.             (int)( getStyle() & DrawStyle.ELLIPSIS | DrawStyle.HALIGN_MASK ),
106.             getWidth() - 6 );
107.     }
108.        
109.     /**
110.      * Overridden so that the Event Dispatch thread can catch this event
111.      * instead of having it be caught here..
112.      * @see net.rim.device.api.ui.Field#navigationClick(int, int)
113.      */
114.     protected boolean navigationClick(int status, int time){
115.         fieldChangeNotify(1);
116.         return true;
117.     }
118.    
119. }