How to fix this bug?

Assalamu alikom,

i'm doing a sample canvas to display 9 screen buttons - like 1..9 standard phone buttons - with pointer event; when moving the mouse pointer within any button area, the button color should be high-lighted (activated).

The problem is: when pointing to a button at the right or the bottom screen boundries, i got them not high lighted. (i.e. buttons: 1,2,4,5 highlighted well, the other buttons are acting in a strange way.)

here's my steps:

- define an array [9*4]: -> {x1,y1,x2,y2} for each button coordinates. (Note: space bet buttons =3 pixels... top, left & right screen margin = 5 pixels)

- in pointerPressed, pointerDragged & pointerReleased events i detect the button number i'm pointing to; key_num detects the button that should be high-lighted, or is equal to -1 if no key is focused, i call repaint after that

- in paint() method: i draw the highlighted button, then looping to draw other buttons - except the high-lighted one. i'm also attaching snapshots of the output.

& here's my code:

public class AnimationCanvas extends Canvas {
   
    /** Creates a new instance of AnimationCanvas */
   
    static int key_num= -1;
    int total_width=this.getWidth();
    int total_height=this.getHeight();
    final int BT_W=(int)((total_width-6-10)/3);  //button width
    final int BT_H=(int)((total_height-20-6)/3); //button height
   
    // buttons arr = {x1,y1,x2,y2) -> for each button (9 * 4 array)

    int buttons_arr[][]={{5,5,5+BT_W,5+BT_H},{8+BT_W,5,8+(2*BT_W),5+BT_H},{11+(2*BT_W),5,(total_width-5),5+BT_H},
            {5,8+BT_H,5+BT_W,8+(2*BT_H)},{8+BT_W,8+BT_H,8+(2*BT_W),8+(2*BT_H)},{11+(2*BT_W),8+BT_H,(total_width-5),8+(2*BT_H)},
            {5,11+(2*BT_H),5+BT_W,(total_height-15)},{8+BT_W,11+(2*BT_H),8+(2*BT_W),(total_height-15)},{11+(2*BT_W),11+(2*BT_H),(total_width-5),(total_height-15)}};

    //Font font;
   // int banner_height, txt_width, x_txt;
    //String banner_txt;
    boolean right_to_left=true; // txt direction
    boolean stopped=false;
    boolean pressed=false;
    //Command exit_command,options;
    //Thread thr;
    HelloMidlet midlet;
   
    public AnimationCanvas(HelloMidlet mid) {
        super();
        midlet=mid;
    }
   
    private int getKeyNum(int x,int y)
    {
        for(int i=0;i<9;i++)
        {
            if((x>buttons_arr[i][0])&&(x<buttons_arr[i][2])&&(y>buttons_arr[i][1])&&(y<buttons_arr[i][3]))
                return i;
        }
        return -1;    //x,y doesn't belong to any button
    }
   
    private void handlePointer(int x,int y)
    {
        key_num=getKeyNum(x,y);
        repaint();
    }
   
    protected void pointerPressed(int x, int y)
    {
        pressed=true;
        handlePointer(x,y);
    }

    protected void pointerDragged(int x, int y)
    {
        pressed=false;
        handlePointer(x,y);
    }
   
    protected void pointerReleased(int x, int y)
    {
        pressed=false;
        handlePointer(x,y);
    }
    

    private void draw(Graphics g)
    {
        g.setColor(0,0,139);
        g.fillRect(0,0,getWidth(),getHeight());
       
        //////////// Draw the active button ///////////////////
            if(key_num != -1)
            {
                g.setColor(255,255,255);
                g.fillRect(buttons_arr[key_num][0],buttons_arr[key_num][1],buttons_arr[key_num][2],buttons_arr[key_num][3]);
            }
       
        ///////////// Draw Buttons (1-9) ///////////////////////
        for(int i=0;i<9;i++)
            {
                // draw Button[i]
                if(i!=key_num){
                g.setColor(255,255,255);
                g.drawRect(buttons_arr[i][0],buttons_arr[i][1],buttons_arr[i][2],buttons_arr[i][3]);
                g.setColor(67,110,238);
                g.fillRect(buttons_arr[i][0]+1,buttons_arr[i][1]+1,buttons_arr[i][2]-1,buttons_arr[i][3]-1);
                }
            }

            }
   
    public void paint(Graphics g)
    {  
        draw(g);
    }
   }

Hope someone'll help.

Thanks.