如何在iPhone 显示一个星级评分

http://blog.csdn.net/fanjunxi1990/article/details/8663914

由于项目需求，需要做一个列表，里面有各个商品的评分，就是app store里面所有app的星级评分

下面是DisplayStarView.h

DisplayStarView.m如下

//
// DisplayStarView.m
// testExpress
//
// Created by Juncy_Fan on 13-3-12.
// Copyright (c) 2013年 Juncy_Fan. All rights reserved.
//
#import "DisplayStarView.h"
@implementation DisplayStarView
@synthesize starSize = _starSize;
@synthesize maxStar = _maxStar;
@synthesize showStar = _showStar;
@synthesize emptyColor = _emptyColor;
@synthesize fullColor = _fullColor;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self)
{
self.backgroundColor = [UIColor clearColor];
//默认的星星的大小是 13.0f
self.starSize = 13.0f;
//未点亮时的颜色是灰色的
self.emptyColor = [UIColor colorWithRed:167.0f / 255.0f green:167.0f / 255.0f blue:167.0f / 255.0f alpha:1.0f];
//点亮时的颜色是亮黄色的
self.fullColor = [UIColor colorWithRed:255.0f / 255.0f green:121.0f / 255.0f blue:22.0f / 255.0f alpha:1.0f];
//默认的长度设置为100
self.maxStar = 100;
}
return self;
}
//重绘视图
- (void)drawRect:(CGRect)rect
{
// Drawing code
CGContextRef context = UIGraphicsGetCurrentContext();
NSString* stars = @"★★★★★";
rect = self.bounds;
UIFont *font = [UIFont boldSystemFontOfSize:_starSize];
CGSize starSize = [stars sizeWithFont:font];
rect.size=starSize;
[_emptyColor set];
[stars drawInRect:rect withFont:font];
CGRect clip = rect;
clip.size.width = clip.size.width * _showStar / _maxStar;
CGContextClipToRect(context,clip);
[_fullColor set];
[stars drawInRect:rect withFont:font];
}
- (void)dealloc
{
[_emptyColor release];
[_fullColor release];
[super dealloc];
}
@end

需要怎么去使用呢？很简单，值需要知道评分是多少就OK啦，比如

//评论是4.2分的
DisplayStarView *sv = [[DisplayStarView alloc]initWithFrame:CGRectMake(90, 90, 200, 40)];
[self.view addSubview:sv];
sv.showStar = 4.2*20;
[sv release];
//评论是2.5分的
DisplayStarView *sv1 = [[DisplayStarView alloc]initWithFrame:CGRectMake(90, 90+40, 200, 40)];
[self.view addSubview:sv1];
sv1.showStar = 2.5 * 20;
[sv1 release];
//评论是4.8分的
DisplayStarView *sv2 = [[DisplayStarView alloc]initWithFrame:CGRectMake(90, 90+40+40, 200, 40)];
[self.view addSubview:sv2];
sv2.showStar = 4.8 * 20;
[sv2 release];

运行结果如图所示：

巴特西