加載gif動態圖的三種方式

準備：本地圖片資源，GifView

GifView代碼：

/**
 *  調用結束就開始播放動畫，若是須要用戶指定什麼時候播放的話，只須要把timer的開始放到合適的位置。經過對CFDictonaryRaf 也就是gifProperties的改變，咱們還能夠控制動畫是否循環播放以及循環多少次中止。
 
    經過對index的改變也能夠控制動畫從某幀開始播放。同理，同時改變index和count的話，也能夠控制從某幀到某幀的播放。
    注意：- (void)stopGif;以後才能夠退出這個類。不然timer不會關閉，產生內存泄露。
 */

#import <UIKit/UIKit.h>
#import <ImageIO/ImageIO.h>

@interface GifView : UIView {
    CGImageSourceRef gif; // 保存gif動畫
    NSDictionary *gifProperties;  // 保存gif動畫屬性
    size_t index;// gif動畫播放開始的幀序號
    size_t count;// gif動畫的總幀數
    NSTimer *timer;// 播放gif動畫所使用的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;
}

加載Gif的三種方式：（從網絡或者本地）

- (NSData *)loadDataForIndex:(NSInteger)index {
    NSData *data = nil;
    if (index == 0) {
        //網絡
        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(實現gif動畫播放是經過將動畫文件讀取到CGImageSourceRef，而後用NSTimer來播放的。)
    
    //- (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(不會出現內存問題)

    //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.幀動畫

- (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; //動畫圖片數組
    gifImageView.animationDuration = 5; //執行一次完整動畫所需的時長
    gifImageView.animationRepeatCount = 999;  //動畫重複次數
    [gifImageView startAnimating];
    [self.view addSubview:gifImageView];
}