アルファベットABC…をクルクル螺旋状にまわしてみる。
(XcodeのiOS6 iPhone Simulatorで動かしています。）
ポイント
・文字のカラーは colorWithHue の値をインクリメントしてカラフルに
・タッチ中はそのポイント方向に文字を動かすようにする。
サンプルコード
#import “ViewController.h”
@interface ViewController () {
NSTimer *timer;
int direction;
}
@end
@implementation ViewController
– (void)viewDidLoad
{
[super viewDidLoad];
[self start];
direction = –1;
}
– (void)createWord
{
static int number;
NSArray *words = [@”A B C D E F G H I J K L M N O P Q R S T U V W X Y Z” componentsSeparatedByString:@” “];
UILabel *l = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 30, 30)];
l.font = [UIFont systemFontOfSize:30];
l.text = [words objectAtIndex:number];
l.textColor = [UIColor colorWithHue:number/30.0 saturation:1.0 brightness:1.0 alpha:1.0];
l.backgroundColor = [UIColor clearColor];
l.center = self.view.center;
[self.view addSubview:l];
l.tag = number;
number++;
number = number % [words count];
}
– (void)start
{
timer = [NSTimer scheduledTimerWithTimeInterval:2.0/60.0 target:self selector:@selector(updateDisp:) userInfo:nil repeats:YES];
}
– (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
CGPoint p = [[touches anyObject] locationInView:self.view];
float angle = atan2(p.x – self.view.center.x, -p.y + self.view.center.y) + M_PI * 1.5;
direction = 26 * (angle / (M_PI * 2.0));
}
– (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
CGPoint p = [[touches anyObject] locationInView:self.view];
float angle = atan2(p.x – self.view.center.x, -p.y + self.view.center.y) + M_PI * 1.5;
direction = 26 * (angle / (M_PI * 2.0));
}
– (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
direction = – 1;
}
– (void)updateDisp:(NSTimer*)sender
{
[self createWord];
if ([self.view.subviews count] > 100) {
[[self.view.subviews objectAtIndex:0] removeFromSuperview];
}
for (UIView *v in self.view.subviews) {
float angle = (M_PI/13.0) * v.tag;
if (direction < 0) {
} else {
angle = (M_PI/13.0) * direction;
}
float x = 5 * cos(angle);
float y = 5 * sin(angle);
v.transform = CGAffineTransformTranslate(v.transform, x, y);
}
}
– (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
@end