ios - 如何在iPhone中的UIScrollView中动态添加图像

Question

在我的 iPhone 应用程序中，我从 Web 服务器获取了大约 300 个图像 url，我需要以 3x3 行和列格式在 UIScrollView 上显示所有图像。一旦我从网络服务器获取所有 url，将它们转换为 UIImage 并显示图像。一切工作正常，但是在加载 200 个图像后应用程序崩溃，我已经阅读了很多 UIScrollView 的内存问题，那么我们该如何解决这个问题呢？我也阅读了苹果文档，但不清楚。

Answer 1

这是解决方案，我已在我的应用程序中实现了它。这是我的代码sv_port 是我的 ScrollView 。下载 SDWebImageDownloader 类文件并将其导入到您的项目中。在您的项目中添加相关框架。像imageIO.framework、QuartzCore

现在，在您的 .m 添加

#import "UIImageView+WebCache.h"
#import "SDImageCache.h"
#import "SDWebImageCompat.h"

//function for adding image in your scrollview
-(void)populateImages
{
int x=6,y=6;

for(UIView * view in sv_port.subviews){
    if([view isKindOfClass:[UIImageView class]])
    {
        [view removeFromSuperview]; view = nil;
    }
    if([view isKindOfClass:[UIButton class]])
    {
        [view removeFromSuperview]; view = nil;
    }
}

for(int p=0;p<[Manufacturer count];p++)
{
    UIButton *btnImageButton = [UIButton buttonWithType:UIButtonTypeCustom];
    btnImageButton.frame = CGRectMake(x,y,70,70);
    [btnImageButton setTag:p];
    [btnImageButton addTarget:self action:@selector(nextview:) forControlEvents:UIControlEventTouchUpInside];

    UIActivityIndicatorView *spinny = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    spinny.frame=CGRectMake(btnImageButton.frame.origin.x+25,btnImageButton.frame.origin.y+25, 20, 20);
    spinny.backgroundColor=[UIColor clearColor];
    [spinny startAnimating];

    [sv_port setScrollEnabled:YES];
    [sv_port addSubview:spinny];

    UIImageView *asyncImageView = [[[UIImageView alloc] initWithFrame:btnImageButton.frame] autorelease];
    asyncImageView.backgroundColor=[UIColor clearColor];
    CALayer *layer;
    layer = asyncImageView.layer;
    layer.borderWidth = 0.5;
    layer.cornerRadius = 5;
    layer.masksToBounds = YES;


     [asyncImageView setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@", yourUrl] ]   placeholderImage:[UIImage imageNamed:nil] options:0 andResize:CGSizeMake(btnImageButton.frame.size.width,btnImageButton.frame.size.height) withContentMode:UIViewContentModeScaleAspectFit];
    asyncImageView.contentMode = UIViewContentModeScaleAspectFit;

    [sv_port addSubview:btnImageButton];
    [sv_port addSubview:asyncImageView];
    int imgCntPort=0;

    imgCntPort=(sv_port.frame.size.width/(asyncImageView.frame.size.width));

    ////NSLog(@"imgport %d",imgCntPort);
    if((p+1)%imgCntPort==0)
    {
        x=5;
        y=y+80;
    }
    else
    {
        x=x+80;
    }
}
sv_port.contentSize = CGSizeMake(0, y);
glob_x =0; glob_y =y;
}

希望有帮助..