图片加载内存优化
UIImage内存占用大小：image.size.width * image.size.height * image.scale
优化方向：缩小图片的尺寸大小
/*** 缩放图片至新尺寸 */
+ (UIImage *)scaleImage:(UIImage *)image toSize:(CGFloat)size {
CGFloat imgW = image.size.width;
CGFloat imgH = image.size.height;
if (imgW > size || imgH > size) {
CGFloat sizeW = 0.0, sizeH = 0.0;
if (imgW > imgH) {
sizeH = size;
sizeW = imgW / imgH * size;
} else {
sizeW = size;
sizeH = imgH / imgW * size;
}
UIGraphicsBeginImageContext(CGSizeMake(sizeW, sizeH));
[image drawInRect:CGRectMake(0, 0, sizeW, sizeH)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
} else {
return image;
}
}
