Question

我的问题是：我从服务器获取图像。当我从服务器图像大小138x91获取图像但我给我的图像大小是我的自定义单元格大小85x56。它装载好。但是，当我单击行时，它会增加服务器图像大小。如何在我的tableview中获取图像时减小图像大小以及当我单击row时如何不改变图像大小。解决我的问题。我希望图像从url获取以及如何在iOS中减小图像大小.goto bellow link。
1）。点击之前。
http://radiokhushi.com/siri-admin/uploads/Beforclick.png
2）。。点击
http://radiokhushi.com/siri-admin/uploads/ofterclick.png

这是图像获取索引路径中行的单元格中的数据代码。在显示一个placeholderimage之前加载。

 newsobject.imageView.image = [UIImage imageNamed:@"Placeholder.png"];
 dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
                dispatch_async(queue, ^{
NSURL *url=[NSURL URLWithString:[NSString stringWithFormat:@"%@",[[newsarry objectAtIndex:indexPath.row] objectForKey:@"thumb_file"]]];

                    NSData *data = [NSData dataWithContentsOfURL:url];
                    UIImage *image = [UIImage imageWithData:data];
                    dispatch_async(dispatch_get_main_queue(), ^{

                [tableView cellForRowAtIndexPath:indexPath].imageView.image = image;

            });
        });

Answer 1

试试这个方法：

 UIImage *croppedimg = [self imageWithImage:[UIImage imageNamed:@"image.png"] convertToSize:CGSizeMake(95, 95)]; // here resize your image whatever you want.

 - (UIImage *)imageWithImage:(UIImage *)image convertToSize:(CGSize)size
 {
    UIGraphicsBeginImageContext(size);
    [image drawInRect:CGRectMake(0, 0, size.width, size.height)];
    UIImage *destImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return destImage;
 }

Answer 2

您可以调整图片大小。获得合适的图像大小。

-(UIImage *)resizeImage:(UIImage *)image withWidth:(int) width withHeight:(int) height {

    CGImageRef imageRef = [image CGImage];
    CGImageAlphaInfo alphaInfo = CGImageGetAlphaInfo(imageRef);
    CGColorSpaceRef colorSpaceInfo = CGColorSpaceCreateDeviceRGB();

    if (alphaInfo == kCGImageAlphaNone)
        alphaInfo = kCGImageAlphaNoneSkipLast;

    CGContextRef bitmap;

    if (image.imageOrientation == UIImageOrientationUp | image.imageOrientation == UIImageOrientationDown) {
        bitmap = CGBitmapContextCreate(NULL, width, height, CGImageGetBitsPerComponent(imageRef), CGImageGetBytesPerRow(imageRef), colorSpaceInfo, alphaInfo);

    } else {
        bitmap = CGBitmapContextCreate(NULL, height, width, CGImageGetBitsPerComponent(imageRef), CGImageGetBytesPerRow(imageRef), colorSpaceInfo, alphaInfo);

    }

    if (image.imageOrientation == UIImageOrientationLeft) {
        NSLog(@"image orientation left");
        CGContextRotateCTM (bitmap, DEGREES_TO_RADIANS(90));
        CGContextTranslateCTM (bitmap, 0, -height);

    } else if (image.imageOrientation == UIImageOrientationRight) {
        NSLog(@"image orientation right");
        CGContextRotateCTM (bitmap, DEGREES_TO_RADIANS(-90));
        CGContextTranslateCTM (bitmap, -width, 0);

    } else if (image.imageOrientation == UIImageOrientationUp) {
        NSLog(@"image orientation up");

    } else if (image.imageOrientation == UIImageOrientationDown) {
        NSLog(@"image orientation down");
        CGContextTranslateCTM (bitmap, width,height);
        CGContextRotateCTM (bitmap, DEGREES_TO_RADIANS(-180.));

    }

    CGContextDrawImage(bitmap, CGRectMake(0, 0, width, height), imageRef);
    CGImageRef ref = CGBitmapContextCreateImage(bitmap);
    UIImage *result = [UIImage imageWithCGImage:ref];

    CGContextRelease(bitmap);
    CGImageRelease(ref);

    return result;
}

Answer 3

如果没有在tableview委托中看到代码，很难确定究竟是什么问题。

但是，我在想如果你设置一个合适的contentMode imageView将解决你的问题。

设置图像后，相应地设置contentMode，可能是这样的：

newsobject.imageView.image = [UIImage imageNamed:@"Placeholder.png"];
newsobject.imageView.contentMode = UIViewContentModeScaleToFill;

Answer 4

使用UIImageView+WebCache.h & .m类下载图片。您可以在github或google上搜索这些类。它为您提供了异步下载图像的不同方法，并提供了根据我们的应用程序要求调整图像大小的功能。使用以下方法：

- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder options: (SDWebImageOptions)options  andResize:(CGSize)size withContentMode:(UIViewContentMode)mode;

我希望这可以帮助您解决问题。

Answer 5

[newsobject.allnewsimg setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@",[[newsarry objectAtIndex:indexPath.row] objectForKey:@"image_file"]]]
               placeholderImage:[UIImage imageNamed:@"songs85-56.png"]];

来自网址的图片以及如何减少iPhone中的图片尺寸

5 个答案: