加载gif动态图的三种方式

Bertha 。 2021-12-20 03:13 434阅读 0赞

准备：本地图片资源，GifView

![Image 1][]

GifView代码：

/**
     *  调用结束就开始播放动画，如果需要用户指定何时播放的话，只需要把timer的开始放到合适的位置。通过对CFDictonaryRaf 也就是gifProperties的改变，我们还可以控制动画是否循环播放以及循环多少次停止。
     
        通过对index的改变也可以控制动画从某帧开始播放。同理，同时改变index和count的话，也可以控制从某帧到某帧的播放。
        注意：- (void)stopGif;之后才可以退出这个类。否则timer不会关闭，产生内存泄露。
     */
    
    #import <UIKit/UIKit.h>
    #import <ImageIO/ImageIO.h>
    
    @interface GifView : UIView {
        CGImageSourceRef gif; // 保存gif动画
        NSDictionary *gifProperties;  // 保存gif动画属性
        size_t index;// gif动画播放开始的帧序号
        size_t count;// gif动画的总帧数
        NSTimer *timer;// 播放gif动画所使用的timer
    }
    
    - (id)initWithFrame:(CGRect)frame filePath:(NSString *)_filePath;
    - (id)initWithFrame:(CGRect)frame data:(NSData *)_data;
    - (void)stopGif;

#import "GifView.h"
    #import <QuartzCore/QuartzCore.h>
    
    @implementation GifView
    
    
    - (id)initWithFrame:(CGRect)frame filePath:(NSString *)_filePath{
        
        self = [super initWithFrame:frame];
        if (self) {
            
            gifProperties = [NSDictionary dictionaryWithObject:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:0] forKey:(NSString *)kCGImagePropertyGIFLoopCount]
                                                         forKey:(NSString *)kCGImagePropertyGIFDictionary];
            gif = CGImageSourceCreateWithURL((CFURLRef)[NSURL fileURLWithPath:_filePath], (CFDictionaryRef)gifProperties);
            count =CGImageSourceGetCount(gif);
            timer = [NSTimer scheduledTimerWithTimeInterval:0.12 target:self selector:@selector(play) userInfo:nil repeats:YES];
            [timer fire];
        }
        return self;
    }
    
    - (id)initWithFrame:(CGRect)frame data:(NSData *)_data{
        
        self = [super initWithFrame:frame];
        if (self) {
            
            gifProperties = [NSDictionary dictionaryWithObject:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:0] forKey:(NSString *)kCGImagePropertyGIFLoopCount]
                                                         forKey:(NSString *)kCGImagePropertyGIFDictionary];
            //        gif = CGImageSourceCreateWithURL((CFURLRef)[NSURL fileURLWithPath:_filePath], (CFDictionaryRef)gifProperties);
            gif = CGImageSourceCreateWithData((CFDataRef)_data, (CFDictionaryRef)gifProperties);
            count =CGImageSourceGetCount(gif);
            timer = [NSTimer scheduledTimerWithTimeInterval:0.12 target:self selector:@selector(play) userInfo:nil repeats:YES];
            [timer fire];
        }
        return self;
    }
    
    -(void)play
    {
        index ++;
        index = index%count;
        CGImageRef ref = CGImageSourceCreateImageAtIndex(gif, index, (CFDictionaryRef)gifProperties);
        self.layer.contents = (__bridge id)ref;
        CFRelease(ref);
    }
    -(void)removeFromSuperview
    {
        NSLog(@"removeFromSuperview");
        [timer invalidate];
        timer = nil;
        [super removeFromSuperview];
    }
    - (void)dealloc {
        NSLog(@"dealloc");
        CFRelease(gif);
    }
    - (void)stopGif
    {
        [timer invalidate];
        timer = nil;
    }

加载Gif的三种方式：（从网络或者本地）

- (NSData *)loadDataForIndex:(NSInteger)index {
        NSData *data = nil;
        if (index == 0) {
            //网络
            data = [NSData dataWithContentsOfURL:[NSURL URLWithString:@"http://s14.sinaimg.cn/mw690/005APVsyzy6MFOsVFfv5d&690"]];
        }else {
            //本地
            data = [NSData dataWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"run" ofType:@"gif"]];
        }
        return data;
    }

1.GifView

//第三方GifView(实现gif动画播放是通过将动画文件读取到CGImageSourceRef，然后用NSTimer来播放的。)
        
        //- (id)initWithFrame:(CGRect)frame filePath:(NSString *)_filePath;
        GifView *dataView = [[GifView alloc] initWithFrame:CGRectMake(0, 0, 100, 100) data:data];
        [self.view addSubview:dataView];
    //    [dataView stopGif];

2.webView(不会出现内存问题)

//webView
        UIWebView *webView = [[UIWebView alloc] initWithFrame:CGRectMake(0, 120, 100, 100)];
        webView.backgroundColor = [UIColor redColor];
        webView.scalesPageToFit = YES;
        [webView loadData:data MIMEType:@"image/gif" textEncodingName:nil baseURL:nil];
        [self.view addSubview:webView];

3.帧动画

- (void)runGIFForImage {
        UIImageView *gifImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 240, 100, 100)];
        NSArray *gifArray = [NSArray arrayWithObjects:[UIImage imageNamed:@"1"],
                             [UIImage imageNamed:@"2"],
                             [UIImage imageNamed:@"3"],
                             [UIImage imageNamed:@"4"],
                             [UIImage imageNamed:@"5"],
                             [UIImage imageNamed:@"6"],
                             [UIImage imageNamed:@"7"],
                             [UIImage imageNamed:@"8"],
                             [UIImage imageNamed:@"9"],
                             [UIImage imageNamed:@"10"],
                             [UIImage imageNamed:@"11"],
                             [UIImage imageNamed:@"12"],
                             [UIImage imageNamed:@"13"],
                             [UIImage imageNamed:@"14"],
                             [UIImage imageNamed:@"15"],
                             [UIImage imageNamed:@"16"],
                             [UIImage imageNamed:@"17"],
                             [UIImage imageNamed:@"18"],
                             [UIImage imageNamed:@"19"],
                             [UIImage imageNamed:@"20"],
                             [UIImage imageNamed:@"21"],
                             [UIImage imageNamed:@"22"],nil];
        gifImageView.animationImages = gifArray; //动画图片数组
        gifImageView.animationDuration = 5; //执行一次完整动画所需的时长
        gifImageView.animationRepeatCount = 999;  //动画重复次数
        [gifImageView startAnimating];
        [self.view addSubview:gifImageView];
    }

转载于:https://www.cnblogs.com/hxwj/p/4489077.html

[Image 1]: