WaterfallFlowLayout瀑布流用重写UICollectionViewFlowLayout类实现Demo

/* * This file is part of the SDWebImage package. * (c) Olivier Poitrey <rs@dailymotion.com> * * For the full copyright and license information, please view the LICENSE * file that was distributed with this source code. */ #import "SDWebImageCompat.h" #import "SDWebImageManager.h" /** * Integrates SDWebImage async downloading and caching of remote images with UIButtonView. */ @interface UIButton (WebCache) /** * Get the current image URL. */ - (NSURL *)sd_currentImageURL; /** * Get the image URL for a control state. * * @param state Which state you want to know the URL for. The values are described in UIControlState. */ - (NSURL *)sd_imageURLForState:(UIControlState)state; /** * Set the imageView `image` with an `url`. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. */ - (void)sd_setImageWithURL:(NSURL *)url forState:(UIControlState)state; /** * Set the imageView `image` with an `url` and a placeholder. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param placeholder The image to be set initially, until the image request finishes. * @see sd_setImageWithURL:placeholderImage:options: */ - (void)sd_setImageWithURL:(NSURL *)url forState:(UIControlState)state placeholderImage:(UIImage *)placeholder; /** * Set the imageView `image` with an `url`, placeholder and custom options. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param placeholder The image to be set initially, until the image request finishes. * @param options The options to use when downloading the image. @see SDWebImageOptions for the possible values. */ - (void)sd_setImageWithURL:(NSURL *)url forState:(UIControlState)state placeholderImage:(UIImage *)placeholder options:(SDWebImageOptions)options; /** * Set the imageView `image` with an `url`. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param completedBlock A block called when operation has been completed. This block has no return value * and takes the requested UIImage as first parameter. In case of error the image parameter * is nil and the second parameter may contain an NSError. The third parameter is a Boolean * indicating if the image was retrived from the local cache or from the network. * The fourth parameter is the original image url. */ - (void)sd_setImageWithURL:(NSURL *)url forState:(UIControlState)state completed:(SDWebImageCompletionBlock)completedBlock; /** * Set the imageView `image` with an `url`, placeholder. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param placeholder The image to be set initially, until the image request finishes. * @param completedBlock A block called when operation has been completed. This block has no return value * and takes the requested UIImage as first parameter. In case of error the image parameter * is nil and the second parameter may contain an NSError. The third parameter is a Boolean * indicating if the image was retrived from the local cache or from the network. * The fourth parameter is the original image url. */ - (void)sd_setImageWithURL:(NSURL *)url forState:(UIControlState)state placeholderImage:(UIImage *)placeholder completed:(SDWebImageCompletionBlock)completedBlock; /** * Set the imageView `image` with an `url`, placeholder and custom options. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param placeholder The image to be set initially, until the image request finishes. * @param options The options to use when downloading the image. @see SDWebImageOptions for the possible values. * @param completedBlock A block called when operation has been completed. This block has no return value * and takes the requested UIImage as first parameter. In case of error the image parameter * is nil and the second parameter may contain an NSError. The third parameter is a Boolean * indicating if the image was retrived from the local cache or from the network. * The fourth parameter is the original image url. */ - (void)sd_setImageWithURL:(NSURL *)url forState:(UIControlState)state placeholderImage:(UIImage *)placeholder options:(SDWebImageOptions)options completed:(SDWebImageCompletionBlock)completedBlock; /** * Set the backgroundImageView `image` with an `url`. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. */ - (void)sd_setBackgroundImageWithURL:(NSURL *)url forState:(UIControlState)state; /** * Set the backgroundImageView `image` with an `url` and a placeholder. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param placeholder The image to be set initially, until the image request finishes. * @see sd_setImageWithURL:placeholderImage:options: */ - (void)sd_setBackgroundImageWithURL:(NSURL *)url forState:(UIControlState)state placeholderImage:(UIImage *)placeholder; /** * Set the backgroundImageView `image` with an `url`, placeholder and custom options. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param placeholder The image to be set initially, until the image request finishes. * @param options The options to use when downloading the image. @see SDWebImageOptions for the possible values. */ - (void)sd_setBackgroundImageWithURL:(NSURL *)url forState:(UIControlState)state placeholderImage:(UIImage *)placeholder options:(SDWebImageOptions)options; /** * Set the backgroundImageView `image` with an `url`. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the specified title. The values are described in UIControlState. * @param completedBlock A block called when operation has been completed. This block has no return value * and takes the requested UIImage as first parameter. In case of error the image parameter * is nil and the second parameter may contain an NSError. The third parameter is a Boolean * indicating if the image was retrived from the local cache or from the network. * The fourth parameter is the original image url. */ - (void)sd_setBackgroundImageWithURL:(NSURL *)url forState:(UIControlState)state completed:(SDWebImageCompletionBlock)completedBlock; /** * Set the backgroundImageView `image` with an `url`, placeholder. * * The download is asynchronous and cached. * * @param url The url for the image. * @param state The state that uses the s