iOS 仿商城评价星级

用户可以用手指划过控件上面的若干图像,以此来对电影、软件等项目做出评分。除了简单的滑动,还添加了动画效果。直接上代码,导入到自己项目里就可以直接用



#import "StarSliderA.h"

#define WIDTH [UIScreen mainScreen].bounds.size.width / 20

@interfaceStarSliderA ()

@property (nonatomic, assign) int value;

@end

.m文件
@implementation StarSliderA

- (instancetype)initWithFrame:(CGRect)aFrame{

self = [superinitWithFrame:aFrame];

if (self) {

float offsetCenter = WIDTH;

for (int i = 1; i <= 10; i++) {

UIImageView *imageView = [[UIImageViewalloc] initWithFrame:CGRectMake(0.0f, 0.0f, WIDTH, WIDTH)];

imageView.image = [UIImageimageNamed:@"OFF_ART"];

imageView.center = CGPointMake(offsetCenter, self.intrinsicContentSize.height / 2.0f);

offsetCenter += WIDTH * 1.5f;

[selfaddSubview:imageView];

}

}

self.backgroundColor = [[UIColorblackColor] colorWithAlphaComponent:0.25f];

returnself;

}

- (CGSize)intrinsicContentSize{

returnCGSizeMake(WIDTH * 8.0f, 34.0f);

}

- (void)updateValueAtPoint : (CGPoint)point{

int newValue = 0;

UIImageView *changedView = nil;

for (UIImageView *eachItem in [selfsubviews]) {

if (point.x < eachItem.frame.origin.x) {

eachItem.image = [UIImageimageNamed:@"OFF_ART"];

}

else{

changedView = eachItem;

eachItem.image = [UIImageimageNamed:@"ON_ART"];

newValue++;

}

}

if (self.value != newValue) {

self.value = newValue;

[selfsendActionsForControlEvents:UIControlEventValueChanged];

[UIViewanimateWithDuration:0.15fanimations:^{

changedView.transform = CGAffineTransformMakeScale(1.5f, 1.5f);

} completion:^(BOOL done) {

[UIViewanimateWithDuration:0.1fanimations:^{

changedView.transform = CGAffineTransformIdentity;

}];

}];

}

}

- (BOOL)beginTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event{

CGPoint touchPoint = [touch locationInView:self];

[selfsendActionsForControlEvents:UIControlEventTouchDown];

[selfupdateValueAtPoint:touchPoint];

returnYES;

}

- (BOOL)continueTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event{

CGPoint touchPoint = [touch locationInView:self];

if (CGRectContainsPoint(self.frame, touchPoint)) {

[selfsendActionsForControlEvents:UIControlEventTouchUpInside];

}

else

[selfsendActionsForControlEvents:UIControlEventTouchUpOutside];

[selfupdateValueAtPoint:[touch locationInView:self]];

returnYES;

}

- (void)endTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event{

CGPoint touchPoint = [touch locationInView:self];

if (CGRectContainsPoint(self.bounds, touchPoint)) {

[selfsendActionsForControlEvents:UIControlEventTouchUpInside];

}

else

[selfsendActionsForControlEvents:UIControlEventTouchUpOutside];

}

- (void)cancelTrackingWithEvent:(UIEvent *)event{

[selfsendActionsForControlEvents:UIControlEventTouchCancel];

}

@end