Circular Rotation Of five buttons maintaining equal distance
I want to rotate five buttons on the circumference of an circle (circle with the center (120,120), which is actually center of square view i.e. 240*240) with radius 100. IS it possible to do so, with having interaction with the buttons which are rotating and a proper look.
i have tried '
x = round(cx + redious * cos(angl));
y = round(cy - redious * sin(angl));
NSString *X=[NSString stringWithFormat:@"%f",x];
[xval addObject:[NSString stringWithFormat:@"%@",X]];
NSString *Y开发者_StackOverflow社区=[NSString stringWithFormat:@"%f",y];
[yval addObject:[NSString stringWithFormat:@"%@",Y]];'
to calculate points and:
map.frame= CGRectMake([[fqx objectAtIndex:counter1]intValue],[[fqy objectAtIndex:counter1]intValue], 72, 37);
website.frame= CGRectMake([[fqx objectAtIndex:counter2]intValue],[[fqy objectAtIndex:counter2]intValue], 72, 37);
share.frame= CGRectMake([[fqx objectAtIndex:counter3]intValue],[[fqy objectAtIndex:counter3]intValue], 72, 37);
slideShow.frame= CGRectMake([[fqx objectAtIndex:counter4]intValue],[[fqy objectAtIndex:counter4]intValue], 72, 37);'
to rotate but it generate weird path.. in triangular way.. ('map','share','slideShow','website') ar my buttons.. :P
This was too cute to pass up so here it is. This code is limited to one button rotating but I doubt you'll have trouble extending it to take multiple (hint: use ONE CADisplayLink and rotate all buttons at once in that).
- (void)setupRotatingButtons
{
// call this method once; make sure "self.view" is not nil or the button
// won't appear. the below variables are needed in the @interface.
// center: the center of rotation
// radius: the radius
// time: a CGFloat that determines where in the cycle the button is located at
// (note: it will keep increasing indefinitely; you need to use
// modulus to find a meaningful value for the current position, if
// needed)
// speed: the speed of the rotation, where 2 * M_PI is 1 lap a second
// b: the UIButton
center = CGPointMake(100, 100);
radius = 100;
time = 0;
speed = 2 * M_PI; // <-- will rotate CW 360 degrees per second (1 "lap"/s)
b = [[UIButton buttonWithType:UIButtonTypeRoundedRect] retain];
b.titleLabel.text = @"Hi";
b.frame = CGRectMake(0.f, 0.f, 100, 50);
// we get the center set right before we add subview, to avoid glitch at start
[self continueCircling:nil];
[self.view addSubview:b];
[self.view bringSubviewToFront:b];
CADisplayLink *dl = [CADisplayLink displayLinkWithTarget:self
selector:@selector(continueCircling:)];
[dl addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
}
We also need the actual "continueCircling:" method, which is simply:
- (void)continueCircling:(CADisplayLink *)dl
{
time += speed * dl.duration;
b.center = CGPointMake(center.x + radius * cosf(time),
center.y + radius * sinf(time));
}
I'm sure there are other more nifty ways to solve this, but the above works at least. :)
Edit: I forgot to mention, you will need to add QuartzCore framework and
#import <QuartzCore/QuartzCore.h>
for CADisplayLink.
Edit 2: Found the PI constant (M_PI
), so replaced 3.1415 with that.
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