加载gif图片，过渡效果：
调用：
- (id)initWithGifView:(UIView *)view
{
self = [super initWithView:view];
if (self) {
self.color = [UIColor clearColor];
NSString *filePath = [[NSBundle bundleWithPath:[[NSBundle mainBundle] bundlePath]] pathForResource:@"loading2.gif" ofType:nil];
NSData *imageData = [NSData dataWithContentsOfFile:filePath];
UIImageView *loadingImgView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 110, 90)];
loadingImgView.contentMode = UIViewContentModeCenter;
loadingImgView.image = [UIImage sd_animatedGIFWithData:imageData];
self.customView = loadingImgView;
self.mode = MBProgressHUDModeCustomView;
[view addSubview:self];
[self show:YES];
}
return self;
}
封装：
+ (UIImage *)sd_animatedGIFWithData:(NSData *)data {
if (!data) {
return nil;
}
CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL);
size_t count = CGImageSourceGetCount(source);
UIImage *animatedImage;
if (count <= 1) {
animatedImage = [[UIImage alloc] initWithData:data];
}
else {
NSMutableArray *images = [NSMutableArray array];
NSTimeInterval duration = 0.0f;
for (size_t i = 0; i < count; i++) {
CGImageRef image = CGImageSourceCreateImageAtIndex(source, i, NULL);
duration += [self sd_frameDurationAtIndex:i source:source];
[images addObject:[UIImage imageWithCGImage:image scale:[UIScreen mainScreen].scale orientation:UIImageOrientationUp]];
CGImageRelease(image);
}
if (!duration) {
duration = (1.0f / 10.0f) * count;
}
animatedImage = [UIImage animatedImageWithImages:images duration:duration];
}
CFRelease(source);
return animatedImage;
}
+ (float)sd_frameDurationAtIndex:(NSUInteger)index source:(CGImageSourceRef)source {
float frameDuration = 0.1f;
CFDictionaryRef cfFrameProperties = CGImageSourceCopyPropertiesAtIndex(source, index, nil);
NSDictionary *frameProperties = (__bridge NSDictionary *)cfFrameProperties;
NSDictionary *gifProperties = frameProperties[(NSString *)kCGImagePropertyGIFDictionary];
NSNumber *delayTimeUnclampedProp = gifProperties[(NSString *)kCGImagePropertyGIFUnclampedDelayTime];
if (delayTimeUnclampedProp) {
frameDuration = [delayTimeUnclampedProp floatValue];
}
else {
NSNumber *delayTimeProp = gifProperties[(NSString *)kCGImagePropertyGIFDelayTime];
if (delayTimeProp) {
frameDuration = [delayTimeProp floatValue];
}
}
// Many annoying ads specify a 0 duration to make an image flash as quickly as possible.
// We follow Firefox's behavior and use a duration of 100 ms for any frames that specify
// a duration of <= 10 ms. See <rdar://problem/7689300> and <http://webkit.org/b/36082>
// for more information.
if (frameDuration < 0.011f) {
frameDuration = 0.100f;
}
CFRelease(cfFrameProperties);
return frameDuration;
}
+ (UIImage *)sd_animatedGIFNamed:(NSString *)name {
CGFloat scale = [UIScreen mainScreen].scale;
if (scale > 1.0f) {
NSString *retinaPath = [[NSBundle mainBundle] pathForResource:[name stringByAppendingString:@"@2x"] ofType:@"gif"];
NSData *data = [NSData dataWithContentsOfFile:retinaPath];
if (data) {
return [UIImage sd_animatedGIFWithData:data];
}
NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:@"gif"];
data = [NSData dataWithContentsOfFile:path];
if (data) {
return [UIImage sd_animatedGIFWithData:data];
}
return [UIImage imageNamed:name];
}
else {
NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:@"gif"];
NSData *data = [NSData dataWithContentsOfFile:path];
if (data) {
return [UIImage sd_animatedGIFWithData:data];
}
return [UIImage imageNamed:name];
}
}
- (UIImage *)sd_animatedImageByScalingAndCroppingToSize:(CGSize)size {
if (CGSizeEqualToSize(self.size, size) || CGSizeEqualToSize(size, CGSizeZero)) {
return self;
}
CGSize scaledSize = size;
CGPoint thumbnailPoint = CGPointZero;
CGFloat widthFactor = size.width / self.size.width;
CGFloat heightFactor = size.height / self.size.height;
CGFloat scaleFactor = (widthFactor > heightFactor) ? widthFactor : heightFactor;
scaledSize.width = self.size.width * scaleFactor;
scaledSize.height = self.size.height * scaleFactor;
if (widthFactor > heightFactor) {
thumbnailPoint.y = (size.height - scaledSize.height) * 0.5;
}
else if (widthFactor < heightFactor) {
thumbnailPoint.x = (size.width - scaledSize.width) * 0.5;
}
NSMutableArray *scaledImages = [NSMutableArray array];
UIGraphicsBeginImageContextWithOptions(size, NO, 0.0);
for (UIImage *image in self.images) {
[image drawInRect:CGRectMake(thumbnailPoint.x, thumbnailPoint.y, scaledSize.width, scaledSize.height)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
[scaledImages addObject:newImage];
}
UIGraphicsEndImageContext();
return [UIImage animatedImageWithImages:scaledImages duration:self.duration];
}
我调用的类是继承MBProgressHUD的。大家看的时候自己在研究下。