微不足道的图片浏览器

　　因为项目需要对图片进行浏览，而网上一些好的图片浏览框架使用起来比较麻烦，而且需要的代码量较大，于是自行封装了一个图片浏览器。在使用方面我会用一个例子进行说明，而图片浏览的背景可以自定义与该图片浏览器没有关系。个人觉得使用比较方便简单，如果在使用的过程中遇到bug，可以联系1152650004，一起探讨。

　　首先是进度条，用来显示图片加载的进度，代码如下：

 1 //
 2 //  LMFProgressView.m
 3 //  LiPu
 4 //
 5 //  Created by wantexe on 16/7/5.
 6 //  Copyright © 2016年 limingfeng. All rights reserved.
 7 //
 8 
 9 #import "LMFProgressView.h"
10 #import <QuartzCore/QuartzCore.h>
11 
12 @interface LMFProgressView ()
13 @property (nonatomic, strong) UILabel *myLabel;
14 @end
15 
16 @implementation LMFProgressView
17 
18 - (instancetype)initWithFrame:(CGRect)frame
19 {
20     if (self = [super initWithFrame:frame])
21     {
22         self.backgroundColor = [UIColor clearColor];
23         self.myLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 40, 20)];
24         self.myLabel.textColor = [UIColor whiteColor];
25         self.myLabel.textAlignment = NSTextAlignmentCenter;
26         self.myLabel.backgroundColor = [UIColor clearColor];
27         self.myLabel.center = self.center;
28         self.myLabel.font = [UIFont systemFontOfSize:12];
29         [self addSubview:self.myLabel];
30     }
31     return self;
32 }
33 // Only override drawRect: if you perform custom drawing.
34 // An empty implementation adversely affects performance during animation.
35 - (void)drawRect:(CGRect)rect
36 {
37     // 生产出一个圆的路径 -M_PI_2 -M_PI_2+angle*M_PI*2
38     CGPoint circleCenter = CGPointMake(CGRectGetMidX(self.bounds), CGRectGetMidY(self.bounds));
39     CGFloat circleRadius = self.bounds.size.width/2.0;
40     double angle = 1.4;
41     if (angle>2) {
42         angle-=2;
43     }else if (angle>1){
44         angle-=1;
45     }
46     UIBezierPath *circlePath = [UIBezierPath bezierPathWithArcCenter:circleCenter
47                                                               radius:circleRadius
48                                                           startAngle:-M_PI_2
49                                                             endAngle:-M_PI_2+2*M_PI*self.progress
50                                                            clockwise:YES];
51     
52     // 生产出一个圆形路径的Layer
53     CAShapeLayer *shapeLayer = [CAShapeLayer layer];
54     shapeLayer.path = circlePath.CGPath;
55     shapeLayer.strokeColor = [UIColor whiteColor].CGColor;
56     shapeLayer.fillColor = [[UIColor clearColor] CGColor];
57     shapeLayer.lineWidth = 1;
58     //    shapeLayer.lineCap = @"round";
59     
60     // 可以设置出圆的完整性
61     shapeLayer.strokeStart = 0;
62     shapeLayer.strokeEnd = self.progress;
63     [self.layer addSublayer:shapeLayer];
64     
65 }
66 
67 - (void)setProgress:(CGFloat)progress
68 {
69     _progress = progress;
70     NSString *text = [NSString stringWithFormat:@"%li%@", (NSInteger)(self.progress*100), @"%"];
71     self.myLabel.text = text;
72     /*
73      setNeedsDisplay会调用自动调用drawRect方法，这样可以拿到  UIGraphicsGetCurrentContext，就可以画画了。而setNeedsLayout会默认调用layoutSubViews，
74      */
75     [self setNeedsDisplay];
76     if (self.progress >= 1)
77     {
78         [self removeFromSuperview];
79     }
80 }
81 
82 @end

　　接下来是对图片处理的核心代码，主要添加了单击返回事件，双击放大缩小事件，两根手指放大缩小事件，代码如下：

  1 //
  2 //  LMFImageView.m
  3 //  LiPu
  4 //
  5 //  Created by wantexe on 16/7/4.
  6 //  Copyright © 2016年 limingfeng. All rights reserved.
  7 //
  8 /*
  9  最多放大为原图的2倍，超过时要自动缩小；最小缩小为原图的一半
 10  */
 11 #define LMFBIGRATE 2
 12 #define LMFSMALLRATE 0.5
 13 #define SCREENW [UIScreen mainScreen].bounds.size.width
 14 #define SCREENH [UIScreen mainScreen].bounds.size.height
 15 #import "LMFImageView.h"
 16 #import "UIImageView+WebCache.h"
 17 @interface LMFImageView ()
 18 {
 19     NSInteger gestureTimes;
 20     CGRect oringinalFrame;
 21     float _totalScale;
 22     LMFProgressView *lmfProgressView;
 23 }
 24 @end
 25 
 26 @implementation LMFImageView
 27 
 28 - (instancetype)initWithFrame:(CGRect)frame
 29 {
 30     if (self = [super initWithFrame:frame])
 31     {
 32         self.userInteractionEnabled = YES;
 33         self.multipleTouchEnabled = YES;
 34         self.layer.masksToBounds = YES;
 35 //        self.backgroundColor = [UIColor yellowColor];
 36         gestureTimes = 0;
 37         _totalScale = 1;
 38         self.imageView = [[UIImageView alloc] init];
 39         self.imageView.center = CGPointMake(SCREENW*0.5, SCREENH*0.5);
 40         oringinalFrame = self.imageView.frame;
 41         [self addSubview:self.imageView];
 42         
 43         lmfProgressView = [[LMFProgressView alloc] initWithFrame:CGRectMake(0, 0, 40, 40)];
 44         lmfProgressView.center = CGPointMake(SCREENW*0.5, SCREENH*0.5);
 45         [self addSubview:lmfProgressView];
 46     }
 47     return self;
 48 }
 49 
 50 #pragma mark --设置图片地址
 51 - (void)setPictureUrl:(NSString *)url andDefaultPicture:(NSString *)picture
 52 {
 53     __weak typeof(lmfProgressView)weakProgress = lmfProgressView;
 54     [self.imageView sd_setImageWithURL:[NSURL URLWithString:url] placeholderImage:[UIImage imageNamed:picture] options:SDWebImageRetryFailed progress:^(NSInteger receivedSize, NSInteger expectedSize) {
 55         weakProgress.progress = (CGFloat)receivedSize/(CGFloat)expectedSize;
 56         NSLog(@"%f", weakProgress.progress);
 57     } completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
 58         if (error)
 59         {
 60             NSLog(@"图片加载失败");
 61             [weakProgress removeFromSuperview];
 62         }
 63         if (error.description == nil)
 64         {
 65             float width = SCREEN_WIDTH;
 66             float height = width*image.size.height/image.size.width;
 67             self.imageView.frame = CGRectMake(0, 0, width, height);
 68             self.imageView.center = CGPointMake(SCREEN_WIDTH*0.5+10, SCREEN_HEIGHT*0.5);
 69             [weakProgress removeFromSuperview];
 70         }
 71     }];
 72 }
 73 
 74 #pragma mark --否添加两根手指放大缩小的手势
 75 - (void)addPinGesture
 76 {
 77     UIPinchGestureRecognizer *pin = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(zoomImage:)];
 78     [self addGestureRecognizer:pin];
 79 }
 80 #pragma mark --用两根手指来改变图片大小
 81 - (void)changeFrame:(UIPinchGestureRecognizer *)gesture
 82 {
 83     CGFloat scale = gesture.scale;
 84     CGFloat temp = _totalScale + (scale - 1);
 85     [self setTotalScale:temp];
 86     gesture.scale = 1.0;
 87 }
 88 - (void)zoomImage:(UIPinchGestureRecognizer *)recognizer
 89 {
 90     CGFloat scale = recognizer.scale;
 91     CGFloat temp = _totalScale + (scale - 1);
 92     
 93     [self setTotalScale:temp];
 94     recognizer.scale = 1.0;
 95 }
 96 
 97 - (void)setTotalScale:(CGFloat)totalScale
 98 {
 99     if ((_totalScale < 0.5 && totalScale < _totalScale) || (_totalScale > 3.0 && totalScale > _totalScale)) return; // 最大缩放 2倍,最小0.5倍
100     
101     [self zoomWithScale:totalScale];
102 }
103 
104 - (void)zoomWithScale:(CGFloat)scale
105 {
106     _totalScale = scale;
107     self.imageView.transform = CGAffineTransformMakeScale(scale, scale);
108     
109     CGRect rect = self.imageView.frame;
110     if (scale > 1)
111     {
112         rect.origin.x = 10;
113     }
114     else
115     {
116         rect.origin.x = (SCREEN_WIDTH-rect.size.width)/2.0+10;
117     }
118     self.imageView.frame = rect;
119     [self setContentSize:CGSizeMake(self.imageView.frame.size.width, self.imageView.frame.size.height)];
120 
121 }
122 #pragma mark --将图片变回到原图大小
123 - (void)changeFrameToOringinal
124 {
125     //变回原图
126     [UIView animateWithDuration:0.3 animations:^{
127         self.imageView.frame = oringinalFrame;
128         self.imageView.center = CGPointMake(SCREENW*0.5, SCREENH*0.5);
129     }];
130 }
131 #pragma mark --变回原图的2倍大小
132 - (void)changeframeToTwoTimes
133 {
134     CGRect frame = self.frame;
135     //变大两倍
136     frame.size = CGSizeMake(frame.size.width*LMFBIGRATE, frame.size.height*LMFBIGRATE);
137     [UIView animateWithDuration:0.3 animations:^{
138         self.imageView.frame = frame;
139         self.imageView.center = CGPointMake(SCREENW*0.5, SCREENH*0.5);
140     }];
141 }
142 
143 #pragma mark --添加单击双击手势
144 - (void)addSingleAndDoubleGesture
145 {
146     UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(dismiss:)];
147     tap.numberOfTapsRequired = 1;
148 //    [self addGestureRecognizer:tap];
149     UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(bigImage:)];
150     doubleTap.numberOfTapsRequired = 2;
151     [self addGestureRecognizer:doubleTap];
152     [tap requireGestureRecognizerToFail:doubleTap];
153 }
154 #pragma mark --单击手势
155 - (void)dismiss:(UITapGestureRecognizer *)gesture
156 {
157     self.block();
158 }
159 #pragma mark --双击手势
160 - (void)bigImage:(UITapGestureRecognizer *)gesture
161 {
162     CGRect frame = self.imageView.frame;
163     if (gestureTimes%2 == 0)
164     {
165         //变大两倍
166         frame.size = CGSizeMake(frame.size.width*LMFBIGRATE, frame.size.height*LMFBIGRATE);
167         [UIView animateWithDuration:0.3 animations:^{
168             self.imageView.frame = frame;
169             self.imageView.center = CGPointMake(SCREENW*0.5, SCREENH*0.5);
170         }];
171     }
172     else
173     {
174         //变回原图
175         [self changeFrameToOringinal];
176     }
177     gestureTimes++;
178 }
179 #pragma mark --隐藏加载条
180 - (void)hiddenProgress
181 {
182     lmfProgressView.hidden = YES;
183 }
184 
185 @end

　　

 1 //
 2 //  LMFImageView.h
 3 //  LiPu
 4 //
 5 //  Created by wantexe on 16/7/4.
 6 //  Copyright © 2016年 limingfeng. All rights reserved.
 7 //
 8 
 9 #import <UIKit/UIKit.h>
10 #import "LMFProgressView.h"
11 typedef void(^dismissBlock)();
12 typedef void(^bigFrameBlock)(CGRect);
13 
14 @interface LMFImageView : UIScrollView
15 
16 @property (nonatomic, copy) dismissBlock block;
17 @property (nonatomic, copy) bigFrameBlock bigFrameBlock;
18 @property (nonatomic, strong) UIImageView *imageView;
19 #pragma mark --否添加两根手指放大缩小的手势
20 - (void)addPinGesture;
21 #pragma mark --将图片变回到原图大小
22 - (void)changeFrameToOringinal;
23 #pragma mark --添加单击双击手势
24 - (void)addSingleAndDoubleGesture;
25 #pragma mark --设置图片地址
26 - (void)setPictureUrl:(NSString *)url andDefaultPicture:(NSString *)picture;
27 #pragma mark --隐藏加载条
28 - (void)hiddenProgress;
29 @end
posted @ 2016-07-13 13:42  照顾一下  阅读(583)  评论(2)  编辑  收藏  举报