最终效果
要求：
- Platform: iOS7.0+
- Language: Objective-C
- Editor: Xcode6.0+
实现
- 思路
UIPogressView + UIImage
总得来说，就利用progressView的两个属性：_progressImage【顶图】和_trackImage【底图】实现不同进度值下的评分效果。
-
属性设置
属性设置 交互逻辑代码
注意：_stepValue是指滑动过程中的最小步进值，0.5表示半颗星，1表示一颗星，要求0 < _stepValue <= 1。
-(void)setProgressImage:(UIImage *)progressImage{
super.progressImage = [self configureImage:progressImage];
}
-(void)setTrackImage:(UIImage *)trackImage{
super.trackImage = [self configureImage: trackImage];
}
// 重新计算设置图，使其符合平铺要求
- (UIImage*)configureImage:(UIImage*)image
{
CGFloat width = self.bounds.size.width / 5;
CGSize size = CGSizeMake(width, width);
UIGraphicsBeginImageContextWithOptions(size, false, image.scale);
[image drawInRect:CGRectMake(0, 0, size.width, size.height)];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return [newImage resizableImageWithCapInsets:UIEdgeInsetsZero resizingMode:UIImageResizingModeTile];
}
// 设置progressView的进度
-(void)updateProgressWithTouches: (NSSet<UITouch *> *)touches isMoved: (BOOL)isMoved{
UITouch *touch = touches.anyObject;
CGPoint loc = [touch locationInView:_progressView];
float value = loc.x / _progressView.bounds.size.width;
if (value < 0) {
return;
}
float progress = (_stepValue == 0) ? value : ceil(value * 5 / _stepValue) * _stepValue / 5;
progress = MIN(progress, 1);
_progressView.progress = progress;
}
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
[self updateProgressWithTouches:touches isMoved:false];
}
-(void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
[self updateProgressWithTouches:touches isMoved:false];
}
-(void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
[self updateProgressWithTouches:touches isMoved:true];
}
-(void)touchesCancelled:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
[self updateProgressWithTouches:touches isMoved:false];
}
- 注意
在设置NSLayout时，设置progressView的高度要和icon_star保持一致，宽度为图片的倍数值，否则会显示错乱。
github
https://github.com/BackWorld/HYStarView
本文只是给读者展示了一种独特的最简单的实现方式，如果对你有帮助，别忘了点个❤️哦。
