How can I use a loop to create parallel lines?

[Logan82]

I am trying to draw a grid in my panel, but i can't quite figure out the loop to draw the parallel lines.

Thanks

[jkmyoung]

Could you show us the code you're using to draw a single line?
What output are you getting right now?

[Logan82]

here is the code for my grid without the loops

private void drawgrid(Graphi cs paper) {
paper.setColor( Color.black); // set the color of walls black


paper.drawLine( 50, 50, 250, 50);//draws h line
paper.drawLine( 50, 70, 250, 70);//draws h line
paper.drawLine( 50, 90, 250, 90);//draws h line
paper.drawLine( 50, 110, 250, 110);//draws h line
paper.drawLine( 50, 130, 250, 130);//draws h line
paper.drawLine( 50, 150, 250, 150);//draws h line
paper.drawLine( 50, 170, 250, 170);//draws h line
paper.drawLine( 50, 190, 250, 190);//draws h line
paper.drawLine( 50, 210, 250, 210);//draws h line
paper.drawLine( 50, 230, 250, 230);//draws h line
paper.drawLine( 50, 250, 250, 250);//draws h line

paper.drawLine( 50, 50, 50, 250);//draws v line
paper.drawLine( 70, 50, 70, 250);//draws v line
paper.drawLine( 90, 50, 90, 250);//draws v line
paper.drawLine( 110, 50, 110, 250);//draws v line
paper.drawLine( 130, 50, 130, 250);//draws v line
paper.drawLine( 150, 50, 150, 250);//draws v line
paper.drawLine( 170, 50, 170, 250);//draws v line
paper.drawLine( 190, 50, 190, 250);//draws v line
paper.drawLine( 210, 50, 210, 250);//draws v line
paper.drawLine( 230, 50, 230, 250);//draws v line
paper.drawLine( 250, 50, 250, 250);//draws v line

}
}

[Logan82]

sorry the previous message is my code for my parallel lines drawn ine at a time. This returns a grid, but i would like to improve my code with two loops.

[jkmyoung]

Please use [ code ] [ / code ] tags next time

paper.drawLine( 50, 50, 250, 50);//draws h line
paper.drawLine( 50, 70, 250, 70);//draws h line
These numbers change, starting from 50, adding 20 at a time, until 250

Replace the bolded parts with an integer variable instead:

for (int i = 50; i < = 250; i += 20){
  paper.drawLine(50,i, 250,i);//draws h line
}

Similarly do the same thing for the vertical lines.
paper.drawLine(50, 50, 50, 250);//draws v line
paper.drawLine(70, 50, 70, 250);//draws v line

for (int j = 50; j < = 250; j += 20){
  paper.drawLine(50,j, 250,j);//draws v line
}

If you can keep track, you can even combine the 2!

for (int i = 50; i < = 250; i += 20){
  paper.drawLine(50,i, 250,i);//draws h line
  paper.drawLine(i,50,i, 250);//draws v line
}

[anurag275125]

for(int i=0;i<11;i++)
{
        paper.drawLine(50, 50+i*20, 250, 50+i*20);//draws h line
	paper.drawLine(50+i*20, 50, 50+i*20, 250);//draws v line
}