我正在使用SDWebView图像，我希望在从远程获取图像时将活动指示器显示为占位符。
我在这里尝试了Malek的答案How to show an activity indicator in SDWebImage，但似乎
UIImage *cachedImage = [manager imageWithURL:url];
已弃用。
是否有人使用此库可以告诉我如何在加载图像时插入活动指示器？
修改
根据Michael Frederick的指示，我最终得到了这段代码，一切正常。
UIActivityIndicatorView *activityIndicator = [[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite] autorelease];
activityIndicator.hidesWhenStopped = YES;
activityIndicator.hidden = NO;
[activityIndicator startAnimating];
activityIndicator.center = CGPointMake(self.tipImage.frame.size.width /2, self.tipImage.frame.size.height/2);
[imageView setImageWithURL:[NSURL URLWithString:imageString]
placeholderImage:nil options:SDWebImageProgressiveDownload
success:^(UIImage *image) { [activityIndicator stopAnimating];[activityIndicator removeFromSuperview]; }
failure:^(NSError *error) { [activityIndicator stopAnimating];[activityIndicator removeFromSuperview]; }];
[imageView addSubview:activityIndicator];
答案 0 :(得分：47)
但是，一般来说，你可以在不使用该分支的情况下轻松地完成它：
__block UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:activityStyle];
activityIndicator.center = imageView.center;
activityIndicator.hidesWhenStopped = YES;
[imageView setImageWithURL:[NSURL URLWithString:@"http://www.domain.com/path/to/image.jpg"]
placeholderImage:[UIImage imageNamed:@"placeholder.png"]
success:^(UIImage *image) { [activityIndicator removeFromSuperview]; }
failure:^(NSError *error) { [activityIndicator removeFromSuperview]; }];
[imageView addSubview:activityIndicator];
[activityIndicator startAnimating];
答案 1 :(得分：22)
您就是这样做的：
[imageView setIndicatorStyle:UIActivityIndicatorViewStyleWhite];
[imageView setShowActivityIndicatorView:true];
[imageView sd_setImageWithURL:[NSURL URLWithString:imageUrl] placeholderImage:[UIImage imageNamed:@"defaultl_image"]];
答案 2 :(得分：17)
这是我的解决方案。在该文件中：UIImageView + WebCache.m
找到那个方法并改变：
- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder
{
UIActivityIndicatorView *activity = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:(UIActivityIndicatorViewStyleGray)];
[activity startAnimating];
[activity setFrame:CGRectMake(self.frame.origin.x - 20, self.frame.origin.y - 10, self.frame.size.width, self.frame.size.height)];
[self addSubview:activity];
//[self setImageWithURL:url placeholderImage:placeholder options:0 progress:nil completed:nil];
[self setImageWithURL:url
placeholderImage:placeholder
options:0
completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType)
{
[activity removeFromSuperview];
}];
}
答案 3 :(得分：15)
您可以下载UIActivityIndicator-for-SDWebImage，这是向您的SDWebImage视图添加UIActivityView的最简单方法。使用CocoaPods，只需将此行添加到podfile：
pod 'UIActivityIndicator-for-SDWebImage'
您可以根据自己的喜好使用其中一行：
- (void)setImageWithURL:(NSURL *)url usingActivityIndicatorStyle:(UIActivityIndicatorViewStyle)activityStyle;
- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder usingActivityIndicatorStyle:(UIActivityIndicatorViewStyle)activityStyle;
- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder options:(SDWebImageOptions)options usingActivityIndicatorStyle:(UIActivityIndicatorViewStyle)activityStyle;
- (void)setImageWithURL:(NSURL *)url completed:(SDWebImageCompletionBlock)completedBlock usingActivityIndicatorStyle:(UIActivityIndicatorViewStyle)activityStyle;
- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder completed:(SDWebImageCompletionBlock)completedBlock usingActivityIndicatorStyle:(UIActivityIndicatorViewStyle)activityStyle;
- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder options:(SDWebImageOptions)options completed:(SDWebImageCompletionBlock)completedBlock usingActivityIndicatorStyle:(UIActivityIndicatorViewStyle)activityStyle;
- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder options:(SDWebImageOptions)options progress:(SDWebImageDownloaderProgressBlock)progressBlock completed:(SDWebImageCompletionBlock)completedBlock usingActivityIndicatorStyle:(UIActivityIndicatorViewStyle)activityStyle;
只需导入
#import <UIActivityIndicator-for-SDWebImage/UIImageView+UIActivityIndicatorForSDWebImage.h>
并使用此代码
[imageView setImageWithURL:[NSURL URLWithString:@"https://media.licdn.com/mpr/mpr/wc_200_200/p/1/005/07f/0a3/30cb8dd.jpg"] placeholderImage:[UIImage imageNamed:@"myImage.jpg"] usingActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
答案 4 :(得分：5)
以上代码略有错误。行'activityIndicator.center = imageView.center'没有为您提供正确的坐标以使进度视图居中。对我来说，它显示了细胞下方的指标。
注意 - 我使用的是最新版本的SDWebImage代码，因此方法略有不同。我也在使用UIButton作为imageView
试试这个：
NSURL *url = [NSURL URLWithString:@"www.someimageurl.com"];
__block UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
activityIndicator.frame = cell.imageView.bounds;
[cell.imageView addSubview:activityIndicator];
[activityIndicator startAnimating];
[cell.imageView setImageWithURL:url forState:UIControlStateNormal completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType) {
[activityIndicator removeFromSuperview];
}];
答案 5 :(得分：5)
我相信最新版本的sdwebimage这是一种更好的方法。
[self.customImageView setImageWithURL:imageURL
placeholderImage:nil
options:nil
progress:^(NSUInteger receivedSize, long long expectedSize) { [self.activityIndicator startAnimating]; }
completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType) { [self.activityIndicator stopAnimating]; }];
注意：如果您没有设置属性，那么self.activityindicator将无效。
我会用Michael Frederick的例子来创建activityindicator。
答案 6 :(得分：4)
SDWebImage具有内置的活动指示器，可以完美地运行。试试这个：
斯威夫特3：
imgView.setShowActivityIndicator(true)
imgView.setIndicatorStyle(.gray)
imgView.sd_setImage(with: URL(string: urlString), placeholderImage: UIImage(named: "placeholder"))
答案 7 :(得分：3)
与SWIFT 4中的上述代码相同：
let activityIndicator = UIActivityIndicatorView.init(activityIndicatorStyle: UIActivityIndicatorViewStyle.gray)
activityIndicator.center = addImage.center
activityIndicator.hidesWhenStopped = true
addImage.sd_setImage(with: URL(string: feed.image), completed: { (image: UIImage?, error: Error?, cacheType: SDImageCacheType, imageURL: URL?) in
activityIndicator.removeFromSuperview()
})
addImage.addSubview(activityIndicator)
activityIndicator.startAnimating()
答案 8 :(得分：2)
[cell.dreamImageView setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@",dream.thumbnail]] placeholderImage:[UIImage imageNamed:@"dream_bg_2.png"] options:0 progress:^(NSInteger receivedSize, NSInteger expectedSize) {
CGFloat domandeFloat = [[NSNumber numberWithInt: receivedSize] floatValue];
CGFloat corretteFloat = [[NSNumber numberWithInt: expectedSize] floatValue];
float currentProgress = domandeFloat/corretteFloat;
NSLog(@"progress %f",currentProgress);
cell.progressView.progress = currentProgress;
//[self.dreamsTableView reloadData];
} completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType) {
cell.progressView.hidden = YES;
}];
答案 9 :(得分：2)
为Swift 2.0更新解决方案，使用SDWebImage加载图片网址
imageView.setShowActivityIndicatorView(true)
imageView.setIndicatorStyle(.White)
答案 10 :(得分：1)
根据CanÜrek的回答，您可能想要创建一个类别，以便更容易在多个应用程序中使用，而无需修改SDWebImage框架。
标题文件：
#import <UIKit/UIKit.h>
#import <SDWebImage/UIImageView+WebCache.h>
@interface UIImageView (WebCacheWithActivityIndicator)
- (void)setImageShowingActivityIndicatorWithURL:(NSURL *)url completed:(SDWebImageCompletedBlock)completedBlock;
@end
实施档案：
#import "UIImageView+WebCacheWithActivityIndicator.h"
@implementation UIImageView (WebCacheWithActivityIndicator)
- (void)setImageShowingActivityIndicatorWithURL:(NSURL *)url completed:(SDWebImageCompletedBlock)completedBlock
{
UIActivityIndicatorView* activityIndication = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[activityIndication setFrame:CGRectMake((self.frame.size.width - activityIndication.frame.size.width) / 2 , (self.frame.size.height - activityIndication.frame.size.height) / 2 , activityIndication.frame.size.width , activityIndication.frame.size.width)];
[self addSubview:activityIndication];
[activityIndication startAnimating];
[self setImageWithURL:url completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType) {
if(completedBlock)
{
completedBlock(image,error,cacheType);
}
[activityIndication stopAnimating];
[activityIndication removeFromSuperview];
}];
}
@end
希望它可以帮助你们帮助你们
干杯
答案 11 :(得分：1)
对于Swift 5.0和SDWebImage 5.0：
替换
#COMBO MAKER
def combo_input_maker():#<--Populate combo_maker
# use global cursor instead of local one
cursor.execute("SELECT maker_name FROM makers")
result=[rec[0] for rec in cursor]
return result
#COMBO MAKER
#COMBO TYPE
def combo_input_type(event=None):#<--Populate combo_type
some_name = combo_maker.get()#<--Query with value select from combo_maker
# use global cursor
cursor.execute("SELECT t1.type FROM maker_types t1 INNER JOIN makers t2 ON t1.maker_id = t2.id WHERE maker_name = %s", [some_name])
result = [rec[0] for rec in cursor]
# populate combo_type
combo_type['value'] = result
combo_type.current(0)
return result
#COMBO TYPE
# connect DB once
conn = connect_db()
cursor = conn.cursor()
combo_maker = ttk.Combobox(Product,state="readonly")
combo_maker['value'] = combo_input_maker() #[item for result in combo_input_maker() for item in result if item]
combo_maker.bind('<<ComboboxSelected>>', combo_input_type) # use function reference here
combo_maker.place(x=5, y=5, height = 25, width = 180)
combo_type = ttk.Combobox(Product,state="readonly")
combo_type.place(x=200, y=5, height = 25, width = 180)
通过
imageView.sd_setShowActivityIndicatorView(true)
imageView.sd_setIndicatorStyle(.gray)
答案 12 :(得分：1)
SdWebImage 5.0
YOUR_IMAGEVIEW.sd_imageIndicator = SDWebImageActivityIndicator.gray
答案 13 :(得分：0)
SDWebImage 5.0支持使用SDWebImageActivityIndicator类显示活动指示器。
let imageView = UIImageView()
imageView.sd_imageIndicator = SDWebImageActivityIndicator.gray
答案 14 :(得分：0)
对我有用的最佳解决方案如下。在下载图像时显示进度指示器是美观且令人鼓舞的。我使用UICircularSlider作为舍入进度视图。你也可以尝试一下。
# Sample data
df = data.frame(col1=c(1,0,3,4,5,6,107,8,9), col2=c(9,8,7,6,5,4,3,2,1))
# col1 col2
# 1 1 9
# 2 0 8
# 3 3 7
# 4 4 6
# 5 5 5
# 6 6 4
# 7 107 3
# 8 8 2
# 9 9 1
# Function to evaluate condition ==0 or 3 digits
cond <- function(x) { any(x==0 | x>=100 & x<=999); }
# Add column telling whether to swap by running the cond function over groups
# of three. Expand the groups again by repeating each value 3 times to match
# the rows.
df$swap = rep(lapply(split(df$col1, ceiling(seq_along(df$col1)/3)), FUN=cond), each=3)
# Swap the indicated rows
df[df$swap==TRUE,][c('col1', 'col2')] = df[df$swap==TRUE,][c('col2', 'col1')]
# Remove the swap column
df <- within(df, rm(swap))
# col1 col2
# 1 9 1
# 2 8 0
# 3 7 3
# 4 4 6
# 5 5 5
# 6 6 4
# 7 3 107
# 8 2 8
# 9 1 9
此处 [_imgPost sd_setImageWithURL:urlPost placeholderImage:zeroImage options:SDWebImageContinueInBackground progress:^(NSInteger receivedSize, NSInteger expectedSize)
{
CGFloat domandeFloat = [[NSNumber numberWithInteger: receivedSize] floatValue];
CGFloat corretteFloat = [[NSNumber numberWithInteger: expectedSize] floatValue];
float currentProgress = (domandeFloat/corretteFloat)*100;
NSLog(@"progress %.f%%",currentProgress);
DBG(@"%li, %li", receivedSize, expectedSize);
[_progress setValue:currentProgress];
} completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
[_progress setHidden:YES];
}];
是_progress
答案 15 :(得分：0)
当用户反复上下滚动列表时，我的列表相当滞后。我发现当重复调用cellForItemAtIndexPath时，activityindicator已被无限添加。
要解决此问题，请在您的activityindicator中添加一个标记：
activityIndicator.tag = 9999;
在创建UIActivityIndicator之前，添加这些行以删除之前的activityindicator，然后再添加新的：
UIView* toDeleteLoader = [cell viewWithTag:9999];
if(toDeleteLoader != nil){
[toDeleteLoader removeFromSuperview];
}
注意：标记内容可以是您在单元格中使用的任何数字。
答案 16 :(得分：0)
使用更新的library（iOS 8上已解决的崩溃），我们有以下方法 -
- (void)sd_setImageWithURL:(NSURL *)url
{
[self sd_setImageWithURL:url placeholderImage:nil options:0 progress:nil completed:nil];
}
正如我们可以看到添加进度块和已完成块的选项，我们只需在进度块中添加活动指示器并在完成块中删除。
在此处添加活动指标的自定义方法 -
- (void)sd_setImageWithURL:(NSURL *)url {
[self sd_setImageWithURL:url placeholderImage:nil options:0 progress:^(NSInteger receivedSize, NSInteger expectedSize) {
UIActivityIndicatorView *activity = nil;
activity = (UIActivityIndicatorView *)[self viewWithTag:100000];
if (!activity) {
activity = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[activity setTag:100000];
[activity setHidesWhenStopped:YES];
[activity setCenter:CGPointMake(self.frame.size.width/2.0f,self.frame.size.height/2.0f)];
[self addSubview:activity];
}
else {
[activity setCenter:CGPointMake(self.frame.size.width/2.0f,self.frame.size.height/2.0f)];
}
[activity startAnimating];
} completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
UIActivityIndicatorView *activity = (UIActivityIndicatorView *)[self viewWithTag:100000];
if ([activity isKindOfClass:[UIActivityIndicatorView class]]) {
[activity stopAnimating];
}
}];
}
这将在正在下载图像时将UIActivityIndicatorView添加到UIImageView的中心，并在完成时删除。
答案 17 :(得分：0)
另一种解决方案是使用动画图像作为占位符图像：
[UIImage animatedImageNamed:@"animated_placeholder" duration:1]