draw2

DrawView.h
#import <UIKit/UIKit.h>
 
 
@interface DrawView : UIView {	
	NSMutableArray *points;
}
@property (retain) NSMutableArray *points;
@end
 
----------------------
.m file:
#import "DrawView.h"
 
#define POINT(X)	[[self.points objectAtIndex:X] CGPointValue]
 
UIColor *current;
 
@implementation DrawView
 
@synthesize points;
 
- (id)initWithFrame:(CGRect)frame {
    if ((self = [super initWithFrame:frame])) {
        // Initialization code
	current = [UIColor whiteColor];
    }
    return self;
}
 
- (void)drawRect:(CGRect)rect {
    // Drawing code
	if (!self.points) return;
	if (self.points.count < 2) return;
 
	CGContextRef context = UIGraphicsGetCurrentContext();
	[current set];
	CGContextSetLineWidth(context, 4.0f);
 
	for (int i = 0; i < (self.points.count - 1); i++)
	{
		CGPoint pt1 = POINT(i);
		CGPoint pt2 = POINT(i+1);
		CGContextMoveToPoint(context, pt1.x, pt1.y);
		CGContextAddLineToPoint(context, pt2.x, pt2.y);
		CGContextStrokePath(context);
	}
 
}
 
- (void)dealloc {
    [super dealloc];
}
 
#pragma mark -
#pragma mark UI Touches
#pragma mark -
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event 
{ 	
	self.points = [NSMutableArray array];
	CGPoint pt = [[touches anyObject] locationInView:self];
	[self.points addObject:[NSValue valueWithCGPoint:pt]];
}
 
- (void) touchesMoved:(NSSet *) touches withEvent:(UIEvent *) event
{
	CGPoint pt = [[touches anyObject] locationInView:self];
	[self.points addObject:[NSValue valueWithCGPoint:pt]];
	[self setNeedsDisplay];
}
 
@end
 
==========================
DrawViewController.m
....
- (void)viewDidLoad {
    [super viewDidLoad];
 
	DrawView *tv = [[DrawView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 240.0f, 240.0f)];
	tv.center = CGPointMake(160.0f, 140.0f);
	[self.view addSubview:tv];
	[tv release];	
}