我开发了一个旋转木马视图，看起来像下面的图片
How do I calculate the position of a view animated from a 3-D carousel?
#pragma mark -
#pragma mark - VIEW LIFE CYCLE
- (void)viewDidLoad
{
[super viewDidLoad];
// VIEW FRAME
CGRect Frame = CGRectMake(-40, -40, 80, 80);
// CREATE 6 VIEWS
_CarouselView = [[NSMutableArray alloc] initWithCapacity:6];
int c = 5;
while(c--)
{
UIView *View = [[UIView alloc] initWithFrame:Frame];
View.backgroundColor = [UIColor colorWithRed:(c&4) ? 1.0 : 0.0 green:(c&2) ? 1.0 : 0.0 blue:(c&1) ? 1.0 : 0.0 alpha:1.0];
[_CarouselView addObject:View];
[self.view addSubview:View];
}
_CurrentAngle = _LastAngle = 0.0f;
[self setCarouselAngle:_CurrentAngle];
}
- (void)viewDidUnload
{
}
#pragma mark -
#pragma mark - VIEW TOUCH GESTURE
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
if(!_TrackingTouch)
{
_TrackingTouch = [touches anyObject];
[_AnimationTimer invalidate];
_AnimationTimer = nil;
_LastAngle = _CurrentAngle;
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
if([touches containsObject:_TrackingTouch])
{
// USE MOVEMENT TO DEVICE HOW MUCH TO ROTATE THE CAROUSEL
CGPoint LocationNow = [_TrackingTouch locationInView:self.view];
CGPoint LocationThen = [_TrackingTouch previousLocationInView:self.view];
_LastAngle = _CurrentAngle;
_CurrentAngle += (LocationNow.x - LocationThen.x) * 180.0f / self.view.bounds.size.width;
// the 180.0f / self.view.bounds.size.width just says "let a full width of my view
// be a 180 degree rotation"
// and update the view positions
[self setCarouselAngle:_CurrentAngle];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
if([touches containsObject:_TrackingTouch])
{
_TrackingTouch = nil;
_AnimationTimer = [NSTimer scheduledTimerWithTimeInterval:0.04 target:self selector:@selector(animateAngle) userInfo:nil repeats:YES];
}
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
[self touchesEnded:touches withEvent:event];
}
#pragma mark -
#pragma mark - CAROUSEL ACTIONS
- (void)setCarouselAngle:(float)Angle
{
// ANGLE TO ADD AFTER EACH ELEM
_AngleToAdd = 360.0f / [_CarouselView count];
// APPLY TO ALL VIEWS
for(UIView *View in _CarouselView)
{
float AngleInRadians = Angle * M_PI / 180.0f;
// GET LOCATION
float x = (self.view.bounds.size.width * 0.5f) + 100.0f * sinf(AngleInRadians);
float y = ((self.view.bounds.size.height-200) * 0.5f) + 90.0f * cosf(AngleInRadians);
// ADJUST SCALE BETWEEN 0.75 0.25
float Scale = 0.75f + 0.25f * (cosf(AngleInRadians) + 1.0);
// APPLY TRANSFORMATION
View.transform = CGAffineTransformScale(CGAffineTransformMakeTranslation(x, y), Scale, Scale);
// TWEAK ALPHA
View.alpha = 0.1f + 0.5f * (cosf(AngleInRadians) + 1.0);
// SETTING Z POSITION
View.layer.zPosition = Scale;
// GET THE NEXT ANGLE
Angle += _AngleToAdd;
}
}
- (void)animateAngle
{
float AngleNow = _CurrentAngle;
_CurrentAngle += (_CurrentAngle - _LastAngle) * 0.97f;
_LastAngle = AngleNow;
// PUSH THE NEW ANGLE
[self setCarouselAngle:_CurrentAngle];
if(fabsf(_LastAngle - _CurrentAngle) < 0.001)
{
[_AnimationTimer invalidate];
_AnimationTimer = nil;
}
}
一切正常，但我很难理解在哪里放置分页代码
答案 0 :(得分：1)
我希望这段代码可以帮到你。您只需要创建一个ViewController，然后复制粘贴代码。
// CarruselViewController.m
//
// Created by Rosendo Castillo Perez on 2/25/14.
// Copyright (c) 2014 Fundtech. All rights reserved.
//
#import "CarruselViewController.h"
@interface CarruselViewController ()
{
NSMutableArray *_CarouselView;
CGFloat _CurrentAngle,_LastAngle, _AngleToAdd;
UITouch * _TrackingTouch;
NSTimer * _AnimationTimer;
}
@end
@implementation CarruselViewController
#pragma mark -
#pragma mark - VIEW LIFE CYCLE
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:(BOOL)animated];
// VIEW FRAME
CGRect Frame = CGRectMake(-40, -40, 80, 40);
// CREATE 6 VIEWS
_CarouselView = [[NSMutableArray alloc] initWithCapacity:6];
int c = 0;
while(c < 5)
{
UILabel *View = [[UILabel alloc] initWithFrame:Frame];
View.backgroundColor = [UIColor colorWithRed:(c&4) ? 1.0 : 0.0 green:(c&2) ? 1.0 : 0.0 blue:(c&1) ? 1.0 : 0.0 alpha:1.0];
[View setTextAlignment:NSTextAlignmentCenter];
[View setTextColor:[UIColor whiteColor]];
[View setFont:[UIFont boldSystemFontOfSize:14]];
[View setText:[NSString stringWithFormat:@"%d",c]];
[_CarouselView addObject:View];
[self.view addSubview:View];
c++;
}
_CurrentAngle = _LastAngle = 0.0f;
[self setCarouselAngle:_CurrentAngle];
}
#pragma mark -
#pragma mark - VIEW TOUCH GESTURE
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
if(!_TrackingTouch)
{
_TrackingTouch = [touches anyObject];
[_AnimationTimer invalidate];
_AnimationTimer = nil;
_LastAngle = _CurrentAngle;
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
if([touches containsObject:_TrackingTouch])
{
// USE MOVEMENT TO DEVICE HOW MUCH TO ROTATE THE CAROUSEL
CGPoint LocationNow = [_TrackingTouch locationInView:self.view];
CGPoint LocationThen = [_TrackingTouch previousLocationInView:self.view];
_LastAngle = _CurrentAngle;
_CurrentAngle += (LocationNow.x - LocationThen.x) * 180.0f / self.view.bounds.size.width;
// the 180.0f / self.view.bounds.size.width just says "let a full width of my view
// be a 180 degree rotation"
// and update the view positions
[self setCarouselAngle:_CurrentAngle];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
if([touches containsObject:_TrackingTouch])
{
_TrackingTouch = nil;
_AnimationTimer = [NSTimer scheduledTimerWithTimeInterval:0.04 target:self selector:@selector(animateAngle) userInfo:nil repeats:YES];
}
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
[self touchesEnded:touches withEvent:event];
}
#pragma mark -
#pragma mark - CAROUSEL ACTIONS
- (void)setCarouselAngle:(float)Angle
{
// ANGLE TO ADD AFTER EACH ELEM
_AngleToAdd = 360.0f / [_CarouselView count];
// APPLY TO ALL VIEWS
for(UIView *View in _CarouselView)
{
float AngleInRadians = Angle * M_PI / 180.0f;
// GET LOCATION
float x = (self.view.bounds.size.width * 0.5f) + 100.0f * sinf(AngleInRadians);
float y = ((self.view.bounds.size.height-200) * 0.5f) + 40.0f * cosf(AngleInRadians);
// ADJUST SCALE BETWEEN 0.75 0.25
float Scale = 0.75f + 0.25f * (cosf(AngleInRadians) + 1.0);
// APPLY TRANSFORMATION
View.transform = CGAffineTransformScale(CGAffineTransformMakeTranslation(x, y), Scale, Scale);
// TWEAK ALPHA
View.alpha = 0.1f + 0.5f * (cosf(AngleInRadians) + 1.0);
// SETTING Z POSITION
View.layer.zPosition = Scale;
// GET THE NEXT ANGLE
Angle += _AngleToAdd;
}
}
- (void)animateAngle
{
float AngleNow = _CurrentAngle;
_CurrentAngle += (_CurrentAngle - _LastAngle) * 0.97f;
_LastAngle = AngleNow;
// PUSH THE NEW ANGLE
[self setCarouselAngle:_CurrentAngle];
if(fabsf(_LastAngle - _CurrentAngle) < 0.1)
{
_CurrentAngle = ((int)_CurrentAngle % 360);
if (_CurrentAngle < 0.0)
{
_CurrentAngle += 360.0;
}
[self setCarouselAngle:_CurrentAngle];
int currentAngle = (int) _CurrentAngle;
int angleToAdd = (int) _AngleToAdd;
int residuo = currentAngle % angleToAdd;
if (residuo != 0)
{
forward = (residuo > (angleToAdd / 2));
[_AnimationTimer invalidate];
_AnimationTimer = [NSTimer scheduledTimerWithTimeInterval:0.02 target:self selector:@selector(centerAngle) userInfo:nil repeats:YES];
}
else
{
NSLog(@"angle: %d - index: %d",currentAngle,([_CarouselView count] - ((currentAngle / angleToAdd) % [_CarouselView count])));
}
}
}
BOOL forward = TRUE;
- (void)centerAngle
{
_CurrentAngle += (forward?1.0:-1.0);
[self setCarouselAngle:_CurrentAngle];
int currentAngle = (int) _CurrentAngle;
int angleToAdd = (int) _AngleToAdd;
int residuo = currentAngle % angleToAdd;
if (residuo == 0)
{
_LastAngle = _CurrentAngle = currentAngle;
[self setCarouselAngle:_CurrentAngle];
[_AnimationTimer invalidate];
_AnimationTimer = nil;
NSLog(@"angle: %d - index: %d",currentAngle,([_CarouselView count] - ((currentAngle / angleToAdd) % [_CarouselView count])));
}
}
@end