trollopsviewcontroller.h

//
//  TrollopsViewController.m
//  Trollops
//
//  Created by dph on 3/16/09.
//  Copyright __MyCompanyName__ 2009. All rights reserved.
//

#import "TrollopsViewController.h"
#import "TrollopView.h"
#import <AVFoundation/AVFoundation.h>

@implementation TrollopsViewController

- (void)viewDidLoad {
  [super viewDidLoad];
  [NSTimer scheduledTimerWithTimeInterval:1.0 / 30.0 target:self selector:@selector(paintTrollops) userInfo:nil repeats:YES];
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
  Trollop * trollop;
  
  UITouch *touch = [touches anyObject];
  currentTouch = [touch locationInView:self.view];
  
  trollop = [[Trollop alloc] init];
  trollop.position = currentTouch;
  trollop.velocity = CGPointMake(4.0, 3.0);
  trollop.radius = 20.0;
  [(TrollopView *)self.view addTrollop:trollop];
}

- (void) paintTrollops {
  [(TrollopView *)self.view refresh];
}

- (void)didReceiveMemoryWarning {
  [super didReceiveMemoryWarning]; // Releases the view if it doesn't have a superview
  // Release anything that's not essential, such as cached data
}

- (void)dealloc {
  [super dealloc];
}

@end

trollopview.h

//
//  TrollopView.m
//  Trollops
//
//  Created by dph on 3/16/09.
//  Copyright 2009 __MyCompanyName__. All rights reserved.
//

#import "TrollopView.h"

@implementation TrollopView

@synthesize trollops;

- (id)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
      self.trollops = [[NSMutableArray alloc] init];
      // Initialization code
    }
    return self;
}

- (void)drawRect:(CGRect)rect {
  Trollop *trollop;
  
  for(trollop in trollops) {
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetStrokeColorWithColor(context, [UIColor orangeColor].CGColor);
    CGContextSetLineWidth(context, 1.0);
    CGContextAddEllipseInRect(context, [trollop getRect]);
    CGContextStrokePath(context);
    [trollop update];
  }
}

- (void)refresh {
  [self setNeedsDisplay];
}

- (void)addTrollop:(Trollop *) aTrollop {
  Trollop * trollop;
  [trollops addObject:aTrollop];
}

- (void)dealloc {
  [trollops release];
  [super dealloc];
}

@end