How create graphs(pie and bar graphs) in j2me

Question

hi friends,
how to create graphs in j2me?
plz help me.
regards,
Shruthi R S

Answer 1

Hi Shruti,
I have developed the same application in j2me. I worked on graphs related to stocks. So i think my code can work for u too.
Here is the code for displaying bars:
package project;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Font;
import javax.microedition.lcdui.Graphics;
class BarCanvas extends Canvas {
     public static boolean indicator=true;
     public static int lenght=120;
     int pad=2;
     Font font;
     private int fh;
     String xName = "";
     String yName = "VALUE";
     private int xmargen=15;
     private int ymargen=15;
     private int initialx=0;
     private int initialy=0;
     int scale = 15;
     private int bw=0;
     int index=0;
     int scaleincr;
     int padincr;
     int pady=0;
     String s1;
     //int bars[]={20,30,40,40,50,20,70,80,90};
     int bars[]={20,30,40,50,300};
     int k=bars.length;
     int barinc=scale+bw+pad;
          BarCanvas(String s1){
               this.s1=s1;
               font = Font.getFont(Font.FACE_SYSTEM,
               Font.STYLE_PLAIN, Font.SIZE_SMALL);
               fh = font.getHeight();
               if(s1.equals("Tic"))
                    padincr=2;
                    bw=3;
                    scaleincr=3;
               if(s1.equals("1 minute"))
                    padincr=2;
                    bw=3;
                    scaleincr=3;
               if(s1.equals("5 minutes"))
                    padincr=2;
                    bw=3;
                    scaleincr=15;
               if(s1.equals("15 minutes"))
                    padincr=10;
                    bw=5;
                    scaleincr=15;
               if(s1.equals("Hourly"))
                    padincr=10;
                    bw=5;
                    scaleincr=1;
               if(s1.equals("Daily"))
                    padincr=10;
                    bw=5;
                    scaleincr=1;
               if(s1.equals("Weekly"))
                    padincr=10;
                    bw=5;
                    scaleincr=1;
               }//linecanvas
public void paint(Graphics g) {
                    int width = getWidth();
               int height = getHeight();
               int titleHeight;
               g.setFont(font);
               int titlex1 = font.stringWidth("TIME");
               int titlex = (width-titlex1)/2;
               g.setColor(0,0,0);
               g.fillRect(0, 0, width, height);
               //set text on scales
                    setScaleName( xName, yName, titlex, height, width, g);
               // x axis
                    drawXasxis( g, width, height,xmargen,ymargen);
                         //y axis
                         drawYasxis( g, xmargen, height,ymargen);
                    //horizontal scale
                         drawXhorizontalScales( g, width, height, scale,xmargen,ymargen);
                         //vertical scale
                         drawYVerticalScales(g, width,height,scale,xmargen,ymargen);
                         //draw x scale no.
                         setXScallNo( g, width, height, scale);
//                         draw y scale no.
                         setYScallNo( g, width, height, scale);
                         //draw line.
                         drawBar(g,height);
public void setXScallNo(Graphics g,int width,int height,int scale){
     String s=initialx+"";
     int increment =scaleincr;
     for(int i= xmargen;i<width;i+=scale){
          //G.drawLine(i, height-10, i, height-10);
          g.drawString(s,i,height-2,Graphics.BOTTOM|Graphics.HCENTER);
          s=(initialx+increment)+"";
          increment+=scaleincr;
     return;
public void setYScallNo(Graphics g,int width,int height,int scale){
     String s=initialy+"";
     int increment =scale;
     for(int i= height-ymargen;i>0;i-=scale){
          //G.drawLine(i, height-10, i, height-10);
          g.drawString(s,0,i,Graphics.TOP|Graphics.LEFT);
          s=(initialy+increment)+"";
          increment+=scale;
     return;
public void setScaleName(String xName,String yName,int titlex,int height,int width,Graphics g){
     g.setColor(250,250,250);
     g.drawString("X-scale=10",width-70,3,Graphics.TOP|Graphics.RIGHT);
     g.drawString("Y-scale=10",width-10,3,Graphics.TOP|Graphics.RIGHT);
     g.drawString(xName,width/2,(height-fh),Graphics.TOP|Graphics.LEFT);
     int i=0;
     for(int j=0;j<yName.length();j++){
          String s=yName.charAt(j)+"";
     g.drawString(s,1,(height/2)+i,Graphics.TOP|Graphics.LEFT);
     i=i+10;
     return;
public void drawXasxis(Graphics g,int width,int height,int xmargen,int ymargen){
     g.setColor(0x6FFFFF);
g.drawLine(xmargen, height-ymargen, width , height-ymargen);
return;
public void drawYasxis(Graphics g,int xmargen,int height,int ymargen){
     g.setColor(0x6FFFFF);
     g.drawLine(xmargen,height-ymargen,xmargen,0);
     return;
public void drawXhorizontalScales(Graphics g,int width,int height,int scale,int xmargen,int ymargen){
     g.setColor(0x6FFFFF);
     int j=0;
     while(j<5){
     for(int i= xmargen;i<width;i+=scale)
          g.drawLine(i, height-(ymargen+j), i, height-ymargen);
     j++;
     return;
public void drawYVerticalScales(Graphics g,int width,int height,int scale,int xmargen,int ymargen){
     g.setColor(0x6FFFFF);
     int j=0;
     while(j<5){
     for(int i=height-ymargen;i>0;i-=scale){
          g.drawLine(xmargen+j,i,xmargen+j,i);
     j++;
     return;
public void drawBar(Graphics g,int height){
     int j=1;
     for(int i=index;i<bars.length;i++,j++)
          //g.drawRect(scale+bw*j+pad*j,(height-15)-bars,bw,bars[i]);
          g.drawRect(scale+bw*j+padincr*j,(height-ymargen)-bars[i]-pady,bw,bars[i]);
g.fillRect(scale+bw*j+padincr*j,(height-ymargen)-bars[i]-pady,bw,bars[i]);
public void setData(int length)
public int getData(){
     return 0;
public void keyPressed(int keyCode) {
if ((keyCode==KEY_NUM4))
     initialx=initialx+scaleincr;
          if(s1.equals("5 minutes"))
               if(index==0)
               index=index+3;
               else
               index=index+4;     
          else if(s1.equals("15 minutes"))
               if(index==0)
               index=index+1;
               else
               index=index+1;
          else
               index=index+scaleincr;
          repaint();
          System.out.println(scaleincr);
if ((keyCode==KEY_NUM6))
     if(initialx>0)
          initialx=initialx-scaleincr;
          if(s1.equals("5 minutes"))
               if(index==3)
               index=index-3;
               else
               index=index-4;     
          else if(s1.equals("15 minutes"))
               if(index==1)
               index=index-1;
               else
               index=index-1;
          else
               index=index-scaleincr;
     //index=index-scaleincr;
     repaint();
if ((keyCode==KEY_NUM2))
     if(initialy>0)
     pady=pady+15;
     initialy=initialy-scale;
     repaint();
if ((keyCode==KEY_NUM8))
     pady=pady-15;
     initialy=initialy+scale;
     repaint();
protected void keyReleased(int keyCode)
protected void keyRepeated(int keyCode)
Similarly u can do for lines and candle sticks too.
If u need any help give any mail id to post jad or jar files.
Regards ,
Deepika