//定義宏:

#define kFontSize 14

#define kPhotoCell_Width 300

#define kPhotoCell_MarginBetween 3

#define kPhotoCell_TitleLabel_Height 25

//方法:

+ (CGFloat)heightForRowWithModel:(PhotoInfo *)photoInfo

{

//1.圖片的高度

//讓圖片等比例縮放

//(1)獲取圖片

UIImage *image = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"TSummer" ofType:@"png"]];

//(2)計算圖片的高度

CGFloat imageHeight = [self heightForImage:image];

//2.文本的高度

CGFloat textHeight = [self heightForText:photoInfo.introduction];

//3.返回cell 的總高度

return kPhotoCell_TitleLabel_Height + imageHeight + textHeight + 4 * kPhotoCell_MarginBetween;

}

//單獨計算圖片的高度

+ (CGFloat)heightForImage:(UIImage *)image

{

//(1)獲取圖片的大小

CGSize size = image.size;

//(2)求出縮放比例

CGFloat scale = kPhotoCell_Width / size.width;

CGFloat imageHeight = size.height * scale;

return imageHeight;

}

//單獨計算文本的高度

+ (CGFloat)heightForText:(NSString *)text

{

//設置計算文本時字體的大小,以什麼標准來計算

NSDictionary *attrbute = @{NSFontAttributeName:[UIFont systemFontOfSize:kFontSize]};

return [text boundingRectWithSize:CGSizeMake(kPhotoCell_Width, 1000) options:(NSStringDrawingUsesFontLeading | NSStringDrawingUsesLineFragmentOrigin) attributes:attrbute context:nil].size.height;

}